Updraft Category Archive: Hurricanes

Frosty AM, Thursday rain; Tuesday flakes? 7-day hurricane tracks in 2013?

Posted at 5:34 PM on March 28, 2012 by Paul Huttner (0 Comments)
Filed under: Frost, Hurricanes

37 degrees possible at MSP Airport Thursday morning

Frost possible - even likely in the north & east metro early Thursday

Frost likely north & east of a Fargo-Alex-St. Cloud-NE Metro-La Crosse line

"Hard freeze" likely (28 degrees or colder) for Walker-Duluth-Iron Range & International Falls

Thursday rain moves in from west to east

Severe risk for parts of Iowa and the central plains

Near 80 degrees this weekend??

Snow flakes possible by next Tuesday?

Wet windy & colder early next week

7-Day Hurricane tracks from NHC in 2013?

Latest from 2012 Hurricane Conference this week in Orlando

Source: Twin Cities NWS

Frost recipe: Frosty start Thursday!

Normally we wouldn't even bother writing about the potential for frost in late March...it's a given.

But our last freezing temps at MSP Airport were on March 9th, when the mercury hit 15 degrees.

Temps probably won't dip to 32 at MSP tonight, but with a low near 37, frost is possible in the metro...and even likely in the northeast metro and further north & east in Minnesota and Wisconsin.

A hard freeze is likely in northern Minnesota.

Source: Twin Cities NWS

The old school definition of a "hard freeze" was at least 3 hours of temps at 28 degrees or colder. With temps at those levels for extended time, sensitive plants are more likely to suffer damage. The good news? I'm told most of our hardy shrubs and trees that are leafing out will be fine even with a freeze. Any prematurely blooming flowers could be a different story.

Thursday showers:

The next wave of low pressure spins in Thursday. Look for clouds and showers to increase form the west during the PM hours, and peak rainfall should arrive Thursday evening.

Most models favor anywhere from .20" to .50" of rain by Friday morning.

Source: ISU

Severe risk south:

While a clap of thunder is possible Thursday evening, SPC does not favor any severe weather for Minnesota.

There is a slight risk for severe storms in parts of Iowa and the Midwest Thursday.

Source: SPC

80 this weekend?

Southerly winds will pump in warmer air this weekend. The latest indications are that we could approach 80 both Saturday and Sunday in much of southern Minnesota!

Early spring signs all over the Midwest:

The Midwestern Regional Climate Center (MWCC) has some timely details on just how unusual our early spring is...and what the impacts are.

"Besides early planting, the warm temperatures are causing a variety of other impacts across the Midwest. The unseasonably warm and dry conditions in parts of the Midwest have increased the risk for wildfires in Minnesota and Wisconsin. However, rain over the past few days should ease the risk for wildfires in parts of this region.

Apple and peach trees are blooming in Missouri, Wisconsin, Iowa, and Illinois. The last year fruit trees bloomed this early in the Midwest was in 2007, which resulted in a late freeze on Easter weekend (http://www.ncdc.noaa.gov/special-reports/2007-apr-coldeventhtml), an event that is now leaving orchard owners nervous that a similar freeze could happen again this year. The warm nighttime temperatures are also inhibiting the production of syrup from maple trees in Wisconsin."

Windy, wet & colder Monday & Tuesday?

The GFS (which has not been terribly reliable lately) is insisting on a fairly strong low pressure storm system swirling in the Upper Midwest Monday & Tuesday.

In that scenario, we could see showers and storms evolve by late Sunday night into Monday...and even enough cold air swirling south behind the system to spawn some wet snow flakes by Tuesday.

The system is still evolving...so stay tuned. What seems certain at this pint is that we'll go from shorts to jackets in about 36hours between Sunday PM and Tuesday morning!

Hurricane Conference: 7-Day NHC track forecasts in 2013?

Here's some breaking news from this week's hurricane conference in Orlando.

NHC may start issuing 7-Day track forecasts for hurricanes in 2013.

Source: TWC via Jonhathan Erdman

The current forecasts goe to 5 days....but widely available "spaghetti models" track storms much further out with varying degrees of accuracy.

Hurricane track forecast errors have been cut in half since 1990, and are much better than intensity forecasts.

CSU forecasts this season cite cooler Atlantic Ocean temps as a reason for a below average forecast in 2012. As I've posted here before, I'm not a big fan of seasonal hurricane forecast. They have been horrible may of the past few years...and give a false sense of alarm or security.

Even in a slow season, it only takes one or two big hurricanes making landfall to do great damage. Even in an active season, most or al of the storms may not make a USA landfall...which is exactly what happened in 2010.

The real value is in short term, updated hurricane forecasts as they happen from NHC. Those guys/gals are good...and they save lives!

June 1st marks the start of hurricane season!

PH

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Best fall colors in 10 years? Tropical trouble brewing again

Posted at 5:27 PM on September 8, 2011 by Paul Huttner
Filed under: Fall color, Hurricanes

Here's some breaking news for fall color fans.

According to the Minnesota DNR this may be the best fall color display in Minnesota in 10 years!

It turns out the combination of ample summer rains, combined with our sunny days and cool nights may be just right to get the color to pop this fall.

Here's the pertainent info from MN DNR.

DNR predicts best fall color season in 10 years
(Released September 8, 2011)

Minnesotans are encouraged to keep the camera batteries charged and to not put the tent or the picnic basket away just yet, because the upcoming fall color season could be the best it has been in 10 years, according to the Minnesota Department of Natural Resources (DNR).

"With adequate rain during the growing season for two consecutive years and recent weather patterns that have included the ideal combination of warm, sunny days and cool evenings, we're predicting an especially vivid display of color across the state in the weeks ahead," said Jana Albers, DNR forest health specialist.

Here's Thursday's fall color report. Some splashes of color are now beginning to show in the drought stressed regions of Minnesota.

Colors will increase over the next few weeks and typically peak in the next month.

Hurricane Season 2011: More tropical trouble ahead?

Don't look now, but the Atlantic Hurricane season of 2011 is quietly brewing into a troublesome affair.

Hurricane Irene slammed into the northeast with as much as 7 billion in damage and devastating floods.

Tropical Storm Lee snuck up through the Gulf of Mexico delivering a swath of heavy rains, (over 10" in some areas) and storm damage from Louisiana through the southeast and into Pennsylvania and New York, where mass evacuations are now underway due to flooding.

Flooded roads in Pennsylvania. (AP Photo)

Now, It looks like what will soon become Hurricane Nate may bring trouble to the Gulf of Mexico. With weak and erratic steering currents, where Nate goes may be a wild card. With divergent model track solutions the threat level is growing anywhere from the Mexican Coast to Louisiana and the U.S. Gulf Coast.

Nate could sit, spin and strengthen in the Gulf for a few days and then deliver a flooding deluge somewhere along the Gulf Coast. Depending on the eventual track, there is a chance that drought stricken eastern Texas could benefit from Nate's rainfall,

The there's Maria. The system is forecast to make a close approach to the southeast USA, before rapidly turning away to the northeast just before hitting land. Unlike Nate, track models are tightly grouped and insist Maria will turn to sea before hitting the USA. But it's a little close for comfort at this point.

As we say in the weather biz...stay tuned!

Frosty start to September in northeast MN:

The details from my MPR colleague Mark Seeley.

Topic: Some early September frosts

"The lower dewpoints and milder temperatures this week have been welcomed by most Minnesota citizens. But, for some northern residents the cooler temperatures brought an end to the growing season. Over September 5-6 (Mon-Tue) this week frost occurred in a number of locations, including: Big Fork (32 F), Hibbing (32 F), Orr (32 F), International Falls (31 F), Cook (30 F), Isabella (29 F), Crane Lake (28 F), Brimson (28 F), and Embarrass (26 F)."

New MN wind speed record?

From Mark's Weather Talk newsletter.

Topic: Wrestling with a new state wind speed record

"During the early morning hours of September 1, 2011 a severe thunderstorm was passing over northwestern Minnesota. Shortly after 3 am the Road Weather Information System managed by Mn/DOT in Donaldson near the Kittson and Marshall County line registered a wind gust of 121 mph. This measurement was substantiated by damages inflicted in the surrounding landscape by such strong winds. Since that time the National Weather Service, Minnesota State Climatology Office, and National Climatic Data Center have been trying to determine if this measurement represents a new Minnesota state record for wind speed. The old state record wind speed was 117 mph from a thunderstorm near Alexandria, MN back on July 19, 1983.

There are many problems associated with determining a wind speed record. For example, it is estimated from earlier storm surveys in the state that winds stronger than 120 mph have been associated with some tornadoes in the state. But an instrumental record of the wind speed does not exist. Secondly the wind instruments (anemometers) used over time to measure wind speed have varied in placement and precision. The elevation above ground is important in the measurement of wind speed, as is the sampling interval (3 second, 5 seconds, 30 seconds, etc). The current system used by the National Weather Service is an Ice Free Wind (IFW) sensor, called a sonic anemometer (no moving parts) and measures wind in 1 second intervals, averaging every 3 seconds. The 121 mph wind at Donaldson was measured by an R.M. Young Wind Monitor (aerovane model 05103) which is a mechanical, propeller type instrument. I think it has an accuracy of plus or minus 1 percent and a measurement range up to 224 mph (though lesser wind might destroy its mast)."

PH

Lee soaks the Gulf Coast; USA Hottest summer ever?

Posted at 5:35 PM on September 2, 2011 by Paul Huttner
Filed under: Hurricanes

Some dry air working into Tropical Storm Lee may have spared New Orleans from the threat of 20" rain totals, but the storm continues to soak the area.

Meanwhile high wind and waves pounded Lake Pontchartrain on the north side of The Big Easy.

The slow moving Tropical Storm will deliver a 1-2 punch to the Gulf Coast:

1) Torrential rainfall with rainfall totals likely over 10" will flood parts of Louisiana, Mississippi and Alabama.

2) A persistent east wind, storm surge and pounding waves will hammer the Gulf Coast for the next 3 days.

NOAA 5-day rainfall forecast: a 24" bull's eye over New Orleans?

Katia & Lee: Active tropical display

Check out the Atlantic IR loop below. On the left, Tropical Storm Lee swirls in the Gulf of Mexico. On the right, Hurricane Katia churns westward in the Atlantic.

USA: Hottest summer ever in 2011?

The data won't be released until mid-September, but there are some rumblings that the summer of 2011 may go down as the hottest on record for the USA.

I heard a representative from the Office of the Texas State Climatologist on the Weather Channel Friday hint that preliminary data may show that the summer of 2011 was the hottest on record for the USA.

This would not be a big shocker considering the huge number of records set this summer in the central and southern plains.

Stay tuned for some torrid numbers coming out in the next few weeks.

Labor Day Weekend: A cooler forecast

Another holiday weekend is upon us. After a steamy 94 Thursday and a hot summer, this weekend will have a decidedly different feel.

Look for highs generally in the 60s and 70s this weekend. Lows will dip into the 40s and even 30s in far northeast Minnesota by Labor Day morning.

Scattered showers will be around Saturday, but the rest of the weekend should be dry.

Sunday will feature gusty NW winds of 15-30 mph, and choppy lakes.

Labor Day looks to be the pick of the weekend. Plenty of sun, light winds and highs in the upper 60s north to low 70s south.

Have a great holiday weekend!

PH

2011's last 90? Cooler weekend; T.S. Lee: 20" in New Orleans?

Posted at 4:39 PM on September 1, 2011 by Paul Huttner
Filed under: Heat, Hurricanes

94 degree high in the Twin Cites Thursday

(Hottest day, and 1st 90 degree day since July 31st.)

15 days at or above 90 degrees in 2011 at MSP

13 days on average at or above 90 at MSP annually

If you like it hot, I hope you enjoyed what was likely the hottest day of the rest of 2011 Thursday!

It may also have been the last time the mercury hits 90 in the Twin Cities this year.

September averages 1 day of 90 degree heat each year in the Twin Cities and southern Minnesota. Amazon Jungle heat and humidity levels swamped Minnesota with the brief heat wave of September 1st 2011.

90 degree heat surges north ahead of low pressure Thursday.

Dew points in the 70s pool opver Minnesota Thursday.

Here are some selected readings at 3pm Thursday.

WEATHER ROUNDUP FOR MINNESOTA
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
300 PM CDT THU SEP 01 2011

CITY SKY/WX TMP DP RH WIND PRES REMARKS
ROCHESTER SUNNY 88 72 58 S10 29.79F HX 94
RED WING MOSUNNY 91 72 52 S9 29.72F HX 98
STANTON SUNNY 90 71 52 SE9 29.72F HX 96
DODGE CENTER SUNNY 88 72 58 S8 29.77F HX 94
WINONA SUNNY 93 70 46 CALM 29.78S HX 99
PRESTON SUNNY 94 70 46 SW7 29.82R HX 100

Cool Front Friday:

You'll notice falling temps and humidity levels Friday, as cool front delivers a much more comfortable air mass courtesy of Canada.

The front will trigger a few scattered storms as it moves south. There is a (very) slight risk of a severe storm, but overall dynamics are weak.

Tropical trouble brewing: T.S. Lee may dump heavy rain on Gulf Coast.

NHC gives the growing disturbance in the Gulf an 80% chance of becoming Tropical Storm Lee in the next 48 hours.

"A BROAD AREA OF LOW PRESSURE LOCATED A COUPLE HUNDRED MILES SOUTH OF THE LOUISIANA COAST IS PRODUCING A LARGE AREA OF CLOUDINESS...
THUNDERSTORMS...AND GUSTY WINDS OVER THE EASTERN AND CENTRAL GULF
OF MEXICO. UPPER-LEVEL WINDS ARE FORECAST TO BECOME MORE CONDUCIVE
FOR DEVELOPMENT...AND THIS SYSTEM COULD BECOME A TROPICAL
DEPRESSION DURING THE NEXT DAY OR SO. A NOAA HURRICANE HUNTER
AIRCRAFT IS SCHEDULED TO INVESTIGATE THE AREA LATER THIS AFTERNOON. THIS SYSTEM HAS A HIGH CHANCE...80 PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS AS IT MOVES SLOWLY NORTHWESTWARD. INTERESTS ALONG THE ENTIRE NORTHERN GULF OF MEXICO COAST SHOULD MONITOR THE PROGRESS OF THIS DISTURBANCE."

Forecast models are moving "Lee" slowly toward the north.

The slow movement means the central Gulf Coast will likely get hammered with torrential rainfall over the next few days. Southern Louisiana, including New Orleans, and Mississippi could pick up 10" to 20" rain totals.

Meanwhile Katia continues to churn westward in the Atlantic. The latest trends in steering currents keep Katia moving more west than north. NHC has adjusted the forecast track westward to reflect the left leaning trend in guidance.

That will bring Katia dangerously close to the Carolina coast late next week. Most of the models stil insist on then recurving Katia and accelerating the storm to the north, east of the U.S. mainland.

But if the track stays any farther west Katia could become a threat to the eastern USA.

Stay tuned!

PH

Summer returns: 96 Thursday - then 40's by Labor Day?

Posted at 8:00 AM on August 31, 2011 by Paul Huttner (2 Comments)
Filed under: Hurricanes

Welcome the Minnesota weather roller coaster!

71 degree high at MSP at 11:49am Tuesday.
(Coolest high temps in 68 days since June 25th when it was 68 degrees!)

66 degrees with drizzle by 5pm Tuesday

Scattered frost near Ely by Labor Day?

It's that time of year again. A "high amplitude" jet stream pattern will bring some rather dramatic weather changes to Minnesota in the next week, and beyond.

Undulating jet stream pattern ahead. (Image courtesy Weatherbank.)

What meteorologists refer to as a "push-pull" weather pattern will bring a series of warm and cold front through Minnesota. This time of year, there's still plenty of warm summery air to the south, and developing cold air to the north.

As low pressure systems swing through, cold air is pushed in behind, then warm air is pulled up ahead of the next system.

Mid 90s Thursday?

That sets us up for some big weather changes in the next month, with potentially dramatic and extreme temperatures swings.

Only in Minnesota can you go from coconut oil to polar fleece in 72 hours!

Foggy start; then sun returns today:

Labor Day Weekend weather shocker: Fall like cold front still on track?

This may be a shock to the system.

After we've bathed in warmer than average temps for the past 3 months, it looks like temperatures may crash this weekend on gusty northwest winds.

Forecast models develop a potent looking low pressure system will develop right over Minnesota this weekend. That means a likely shot of rain, and the season's first strong late summer (early meteorological fall!) cold front will slam south by Sunday.

Saturday night into Sunday is looking wet, windy and raw at this point, with highs only in the 60s and a gusty northwest wind making it feel like....gulp...50s up north?

With lows in the 40s by Labor Day morning, some parts of Minnesota may literally go from AC to heat in just over 72 hours.

Katia reaching hurricane force:

Tropical Storm Katia should become "Hurricane Katia" today.

The latest hurricane "spaghetti tracks" still steer Katia out to sea east of the USA in about 10 days.

Stay tuned!

PH

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Irene's toll in numbers; Dry August; Rain tomorrow?

Posted at 9:06 AM on August 29, 2011 by Paul Huttner (2 Comments)
Filed under: Hurricanes

Sometimes you just can't win.

With criticism flying at everyone from New York City mayor to the media, you'd think Irene had taken a sharp right turn and gone out to sea before hitting the USA.

Instead Irene was, as advertised, the first hurricane to make landfall in the USA in nearly 3 years, and it cut a swath through the most densely populated part of the USA.

We have just witnessed a major success story when it comes to saving life and property. We just pulled off a major, well organized and executed mass evacuation, with a high degree of "situational awareness" thanks to broad media coverage. More on that below, but first a look at Irene's toll through the numbers, (with some of my comments regarding they "hype" accusations with Irene.)

21 people killed by Irene at last count. (Isn't that a major news story all by itself? How much media coverage would we have seen if 21 people had been blown up in Time's Square, or shot in an attack at a local mall?)

4.5 million people without power. (If it was a "blackout" the cable networks would be in nonstop coverage)

7 billion dollars in estimated losses from Irene. (That's billion with a big "B")

9,000 flights cancelled due to the storm

5 places Highway 12 on North Carolina's Outer banks was wiped out by Irene's surge.

2,500 people cut off from the mainland on North Carolina's Outer Banks.

2 landfalls as a hurricane in North Carolina and New Jersey. (Irene barely diminished to Tropical Storm force before a 3rd landfall in Brooklyn, New York.)

University of Wisconsin precipitable water loop shows Irene spinning up the east coast last weekend.

Too much hype?

Some are saying Irene was over-hyped...probably in large part due to the lack of extensive damage in New York City...where much attention was focused. To be fair there were a few "lame" live shots along the coast during the network and cable coverage, with reporters trying to make more of the weather than was actually happening. But you can make the case that the reporters were in the wrong places; most of the real damage with Irene was well inland in the form of downed trees and heavy flooding.

Each storm is different:

One of the lessons from Katrina and other big storms is that each storm is different. Storms evolve in different ways, and have different impacts that you might not anticipate going in.

I remember the night before Katrina hit New Orleans listening to Matt Drudge on the radio poo pooing the "hype" over Katrina as it "weakened" from Cat 5 to Cat 3 before landfall. Then it appeared New Orleans had dodged a bullet...until reports came in about a breach in a major levee. The rest is history.

The real stories of storms and other natural disasters often comes from what systems or structures fail during or after a storm. Who knew for sure the levees would fail in Katrina? How could we anticipate the failure of seven nuclear reactors in Fukushima after the Tsunami? Who knew the Metrodome roof would collapse during last December's "Domebuster" storm?

Meteorologists often stress "situational awareness" and "being prepared" for severe weather. We just witnessed a huge success story with excellent coordination from federal, state and local governments that probably saved numerous lives and property.

And still, some complain about the "hype." Go figure.

Dry August: Next rain Tuesday?

Have you noticed your grass getting a little dry lately? You're not alone...here's why.

3.01" rainfall so far in August at MSP Airport

-.81" vs. average this month

.12" of rain the past 12 days

Dryness is creeping back into parts of Minnesota lately. Check out the latest U.S. Drought Monitor which shows parts of the I-90 corridor and the North Shore sliding into "abnormally dry" conditions.

Our next shot of rain may come Tuesday. An upper wave should be strong enough to trigger scattered showers and T-Storms. Models are hinting at rainfall totals between .50" and 1" from the metro south.

Summery week overall: Labor Day Weekend cold front?

September starts Thursday and Labor Day is next weekend! How did that happen?

Look for the sun and summery weather to return Wednesday and Thursday. We may see highs in the mid to upper 80s Thursday with some humidity.

It appears a "timely" and fairly strong cold front may blast through by next Sunday. It could feel a little like fall around here by the time Labor Day rolls around. Right on cue for back to school.

The longer range pattern shows summer like warmth may return by the following weekend and last through mid-September. But keep in mind September is a month where the jet stream builds "high amplitude" or big north-south undulations. Patterns and weather maps can go through big changes in a hurry. Forecast models can and probably will show high degree of variability next month. Rapid weather changes in weather become more likey in September.

In the mean time enjoy a week that is on balance more like summer than fall!

PH

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Irene rakes the coast; 65 million in path; NYC rare direct hit?

Posted at 5:20 PM on August 26, 2011 by Paul Huttner (3 Comments)
Filed under: Hurricanes

Here we go.

The hurricane scenario may have dreaded is unfolding this weekend along the east coast.

1km visible image of Irene Friday from NASA Aqua/MODIS satellite

Let's break down some of the many facets of Irene.

Sheer size of Irene the biggest factor:

Irene's sheer size may be the biggest factor is how much damage she eventually does. As many as 65 million people lie in the storms path. Hundreds of thousands of trees may be knocked down from the Carolinas to Maine. Power may be cut to tens of millions.

Storm track:

Hurricane Irene is tracking right along the east coast, and the huge storm is effecting millions in the most densely populated area of the USA.

The suite of spaghetti models continues to be remarkably consistent taking Irene through eastern North Carolina and right along the Jersey Shore into New York City.

A direct hit from a category 1 Hurricane Irene in New York City looks likely at this point.

Even if the center of Irene misses New York, the storm is so large that hurricane force winds (or at least gusts) are almost certain along the entire coast from the Carolina's to New York.

Intensity:

Irene showed signs of dry air intrusion and slight weakening Friday. To my eye however, the CDO with Irene seem to be in up cycle...and further strengthening can't be ruled out before Irene reaches the Carolina coast Saturday.

There are two main reasons why intensity is becoming somewhat of a secondary consideration at this point.

1) The storm is so large that hurricane force wind gusts will be felt over a huge area.

2) The wall of water moving north with Irene (storm surge) is already in motion, and will arrive and flood low lying coastal areas regardless of Irene's eventual intensity at landfall.

New York City: Effects of a direct hit?

There are many scenarios regarding a direct hit of even a Category 1 hurricane on New York City. Not many are good. Here are some of the possible impacts and considerations.

-Storm surge Flooding: Depending on exact storm track, various scenarios put storm surge of 3 to 7 feet along the Jersey Shore and into the New York Harbor system. Add wave up to 9 feet on top of that surge, and you may have significant coastal flooding.

The effects of flooding into New York remain unclear, and potentially dangerous. This kind of scenario doesn't happen often...and the fact is we really don't know how severe the damage and flooding from storm surge will be in New York.

Wind Damage:

So what happens when hurricane force winds batter the tall buildings in New York City? The fact is again, we don't know how extensive the damage will be.

One thing to consider is the increase in wind speeds with height above ground. As you reduce friction above ground, wind speeds will increase.

With category 1 winds of 75+ mph at the ground, you may have category 2 winds of 100mph 10 stories up!

You will also get an increase in wind speeds with the wind tunnel effects between buildings. There could be significant damage to skyscraper windows this weekend, and potentially showers of glass to the streets of New York City.

There are good reasons why mass evacuations are ordered for large areas. We are now living through one great big bad weather experiment!

PH

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Irene Alarm: Mass evacuations? Worst in 70 years? NYC Flood?

Posted at 4:59 PM on August 25, 2011 by Paul Huttner
Filed under: Hurricanes

The hurricane models have shifted west today, and that's sounding alarm bells from North Carolina through New Jersey, New York City, all the way to New England.

Hurricane Irene is ready to move out of the Bahamas and head for North Carolina.

The new track and intensity forecasts are raising the alarm level of several hurricane experts (and this forecaster) about the growing threat of major storm surge flooding and damage to highly populated coastal areas; including New York City.

(Click to enlarge images)

First, the latest on Irene late Thursday.

BULLETIN
HURRICANE IRENE ADVISORY NUMBER 22
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092011
500 PM EDT THU AUG 25 2011

SUMMARY OF 500 PM EDT...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...27.0N 77.3W
ABOUT 575 MI...930 KM S OF CAPE HATTERAS NORTH CAROLINA
MAXIMUM SUSTAINED WINDS...115 MPH...185 KM/H
PRESENT MOVEMENT...NNW OR 335 DEGREES AT 14 MPH...22 KM/H
MINIMUM CENTRAL PRESSURE...950 MB...28.05 INCHES

Irene is already showing the expected intensification as it moves out of the northern Bahamas.

The storm is so large that squalls in spiral rain bands are spinning though Florida.

Track forecasts shift west:

The major development today is that the forecast tracks for Irene have shifted slightly west. This is a big deal, and a major hurricane landfall in North Carolina is now almost certain Saturday.

What's worse, the later tracks bring a Category 2 Irene near or along the Jersey Shore, and perilously close to a rare direct hit on New York City late Sunday.

If that timing works out, the storm could hit at high tide, which could add 5 feet of water to a potential 10-5 foot storm surge.

Below, some eye openeing (and rather alarming) discussion form hurricane expert Jeff Masters and other sources.

Irene an extremely dangerous storm surge threat to the mid-Atlantic and New England

"Back in 1938, long before satellites, radar, the hurricane hunters, and the modern weather forecasting system, the great New England hurricane of 1938 roared northwards into Long Island, New York at 60 mph, pushing a storm surge more than 15 feet high to the coast. Hundreds of Americans died in this greatest Northeast U.S. hurricane on record, the only Category 3 storm to hit the Northeast since the 1800s. Since 1938, there have been a number of significant hurricanes in the Northeast--the Great Atlantic hurricane of 1944, Hazel of 1954, Diane of 1955, Donna of 1960, Gloria of 1985, Bob of 1991, and Floyd of 1999--but none of these were as formidable as the great 1938 storm. Today, we have a hurricane over the Bahamas--Hurricane Irene--that threatens to be the Northeast's most dangerous storm since the 1938 hurricane."

Category 2 landfalls may not sound that significant, since Hurricane Bob of 1991 made landfall over Rhode Island as a Category 2, and did only $1.5 billion in damage (1991 dollars), killing 17. But Irene is a far larger and more dangerous storm than Bob. The latest wind analysis from NOAA/HRD puts Irene's storm surge danger at 4.8 on a scale of 0 to 6, equivalent to a borderline Category 3 or 4 hurricane's storm surge. Bob had a much lower surge potential, due to its smaller size, and the fact it was moving at 32 mph when it hit land. Irene will be moving much slower, near 18 mph, which will give it more time to pile up a big storm surge. The slower motion also means Irene's surge will last longer, and be more likely to be around during high tide. Sunday is a new moon, and tides will be at their highest levels of the month during Sunday night's high tide cycle. Tides at The Battery in New York City (Figure 3) will be a full foot higher than they were during the middle of August. Irene will expand in size as it heads north, and we should expect its storm surge to be one full Saffir-Simpson Category higher than the winds would suggest."

Irene's storm surge potentially extremely dangerous for the mid-Atlantic coast

"Irene's large size, slow motion, arrival at high tide, and Category 3 strength at landfall in North Carolina will likely drive a storm surge of 8 - 10 feet into the heads of bays in Pamlico Sound, and 3 - 6 feet in Albemarle Sound. As the storm progresses northwards, potential storm surge heights grow due to the shape of the coast and depth of the ocean, though the storm will be weakening. If Irene is a Category 1 storm as it crosses into Virginia, it can send a storm surge of 4 - 8 feet into Chesapeake Bay and Norfolk. I give a 50% chance that the surge from Irene in those locations will exceed the record surges observed in 2003 during Hurricane Isabel. The region I am most concerned about, though, is the stretch of coast running from southern Maryland to Central New Jersey, including Delaware and the cities of Ocean City and Atlantic City. A Category 1 hurricane can bring a storm surge of 5 - 9 feet here. Irene's large size, slow movement, and arrival at the highest tide of the month could easily bring a surge one Category higher than the storm's winds might suggest, resulting in a Category 2 type inundation along the coast, near 10 - 15 feet. This portion of the coast has no hurricane experience, and loss of life could be heavy if evacuation orders are not heeded. I give a 30% chance that the storm surge from Irene will bring water depths in excess of 10 feet to the coasts of Maryland, Delaware, and New Jersey."

Irene's storm surge may flood New York City's subway system

"The floodwalls protecting Manhattan are only five feet above mean sea level. During the December 12, 1992 Nor'easter, powerful winds from the 990 mb storm drove an 8-foot storm surge into the Battery Park on the south end of Manhattan. The ocean poured over the city's seawall for several hours, flooding the NYC subway and the Port Authority Trans-Hudson Corporation (PATH) train systems in Hoboken New Jersey. FDR Drive in lower Manhattan was flooded with 4 feet of water, which stranded more than 50 cars and required scuba divers to rescue some of the drivers. Mass transit between New Jersey and New York was down for ten days, and the storm did hundreds of millions in damage to the city. Tropical Storm Floyd of 1999 generated a storm surge just over 3 feet at the Battery, but the surge came at low tide, and did not flood Manhattan. The highest water level recorded at the Battery in the past century came in September 1960 during Hurricane Donna, which brought a storm surge of 8.36 feet to the Battery and flooded lower Manhattan to West and Cortland Streets. However, the highest storm surge on record in New York City occurred during the September 3, 1821 hurricane, the only hurricane ever to make a direct hit on the city. The water rose 13 feet in just one hour at the Battery, and flooded lower Manhattan as far north as Canal Street, an area that now has the nation's financial center. The total surge is unknown from this greatest New York City hurricane, which was probably a Category 2 storm with 110 mph winds. NOAA's SLOSH model predicts that a mid-strength Category 2 hurricane with 100-mph winds could drive a 15 - 20 foot storm surge to Manhattan, Queens, Kings, and up the Hudson River. JFK airport could be swamped, southern Manhattan would flood north to Canal Street, and a surge traveling westwards down Long Island Sound might breach the sea walls that protect La Guardia Airport. Many of the power plants that supply the city with electricity might be knocked out, or their docks to supply them with fuel destroyed. The more likely case of a Category 1 hurricane hitting at high tide would still be plenty dangerous, with waters reaching 8 - 12 feet above ground level in Lower Manhattan. Given the spread in the models, I predict a 20% chance that New York City will experience a storm surge in excess of 8 feet that will over-top the flood walls in Manhattan and flood the subway system. This would most likely occur near 8 pm Sunday night, when high tide will occur and Irene should be near its point of closest approach. Such a storm surge could occur even if Irene weakens to a tropical storm on its closest approach to New York City."

Stay tuned as Irene continues to develop and move toward the eastern USA.

I want to emphasize that it's still too early to make the call on a direct hit for New York City, but the threat is growing with each passing model run. This could very well develop into a major weather disaster.

PH

"Perfect" Fair opener! Irene: Growing threat to New York City?

Posted at 8:16 AM on August 25, 2011 by Paul Huttner
Filed under: Hurricanes

You can't write it up any better (batter?) than this for the Minnesota State Fair. It's all sunshine on a stick at the Fair today.

Some opening day numbers may be as close to "weather perfection" as it gets!

State Fair Microcast:

63 degrees at 6am Thursday when the Fairgrounds opened

76 degrees at noon (much warmer in the Food Building for lunch)

82 degrees at 4pm (Thursday's day's high temperature at Ye Old Mill)

73 degrees at 10pm (With a brightly lit Midway)

53 degree average dew point Thursday. (Ideal for human comfort!)

5-10 mph west wind (Great food smells wafting on a gentle breeze)

Synopsis:

A clear comfortable late August high pressure will drift right over Minnesota Thursday. Low humidity will bring clear sunny skies. Light west winds will be almost perfect at the Fair, with temps peaking in the low 80s between 2pm and 6pm.

Does it get any better for day 1 of the Fair? Bring the sunscreen!

Looking ahead the first weekend of the Fair looks pretty great. The best chance of T-Storms appears to be late Saturday night into Sunday.

Friday: A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 84. South wind 5 to 9 mph becoming west.

Sunday: A slight chance of showers and thunderstorms. Partly sunny, with a high near 75.

Irene: "Textbook" hurricane now

This is how they teach hurricanes in weather school.

Consider some of Hurricane Irene's features as she ramps up toward likely Category 4 strength Thursday.

-Large (beautiful?) concentric cloud shield with well established outflow

-Clear eye developing

-Concentric central dense overcast (COD) surrounding the eye

-Warm ocean SST's in the mid 80s to feed the growing storm

"Beautiful Monster?"

Irene looks simply beautiful from GOES satellites 22,000 miles above the earth. But she's a monster underneath.

The storm now shows near perfect symmetry. It's a textbook example of how hurricanes form and grow.

Eyewall replacement cycles:

Now that Irene has a distinct eye, look for so called "eyewall replacement cycles" to begin. This process of building-decaying-replacing the eyewall is one way the storm intensifies.

The good news?

The good news is model trends continue to push Irene further to the east. Florida and Georgia, and most of South Carolina are now outside the cone of possible landfall.

The bad news:

North Carolina's Outer banks still may take a direct hit, and it is looking increasingly likely that Irene may pose a threat for a rare direct hit on New York City Sunday night.

The latest model trends bring Irene to near New York City by Sunday night as a Category 1 or 2 hurricane with winds of nearly 100mph.

At this point I would say there is a 50-50 chance that Irene may produce significant damage in New York City. The potential for winds of 100mph, 3-5 foot storm surge into the Hudson River and Lower Manhattan is real.

Rare "Heat Burst" hits southwest Iowa Tueday night:

From NWS Des Moines....a rare heat burst spiked temps 15 to 20 degrees in just a few minutes Tuesday night.

Heat Burst Affects Southwest Iowa

"During the evening of August 23, a rare phenomenon known as a heat burst affected portions of southwest Iowa. A heat burst is characterized by a sudden rise in temperature, a drop in humidity, and strong winds that can approach or exceed severe levels. They are associated with high based decaying thunderstorms with a substantial dry layer beneath the base of the storm. As rain from the thunderstorm falls into the underlying dry air, it cools the air immediately around it, which becomes denser than the surrounding air and begins to sink. As this air sinks, it drys and compresses adiabatically, which results in the hot and dry readings recorded with heat bursts."

Observations

A number of weather stations recorded the heat burst as it passed through. The highest wind gust recorded was 60 mph at the Fontanelle schoolnet site, while both the Atlantic AWOS and Fontanelle schoolnet sites recorded a temperature of 102 degrees. To show just how quckly the weather conditions changed as a result of the heat burst, the tabular data from the Atlantic AWOS is shown below.

Atlantic AWOS Data
Time (CDT) Temp (F)
Dew Point (F)
Wind

5:55pm 84 75 Calm
6:05pm 86 61 16 G 28 mph
6:15pm 93 54 21 G 41 mph
6:25pm 88 61 10 G 39 mph
6:35pm 86 59 12 mph
6:45pm 86 61 14 mph
6:55pm 88 64 16 G 26 mph
7:05pm 90 54 20 G 30 mph
7:15pm 99 18* 8 G 38 mph
7:25pm 102 7* 3 mph
7:35pm 91 52 Calm
7:45pm 88 64 10 G 18 mph
7:55pm 84 72 13 G 21 mph
8:05pm 84 75 8 mph

*AWOS sites typically have problems reporting dew points in low humidity environments, so these two dew point measurements are likely incorrect.

NASA Images: African Dust, Dismal Swamp fires

It's amazing how beautiful our planet is form space. Check out these NASA MODIS Terra images from NASA'a Earth Observatory this week.

Studies have show African dust from the Sahara desert can travel all the way across the Atlantic and end up in the soil in Florida. You can see how that can happen below.

The "Great Dismal Swamp" (sounds like a great vacation destination huh?) in Virginia is a strange place, and this year it's on fire. Check out the smoke plume form space.

Just a little reminder how very small we are in a really big world.

Enjoy our fine late August weather pattern, and open those windows for "good sleeping weather" the next few nights!

PH

Relief! Windy "fresh front" arrives; Irene: Threat to NYC & Bos?

Posted at 8:49 AM on August 24, 2011 by Paul Huttner
Filed under: Hurricanes

How do you spell relief?

C-O-L-D F-R-O-N-T!

The first of a series of Canadian cool fronts slipped through Minnesota overnight.

The front silently but dramatically dropped dew points. The dew point at MSP Airport plunged from a tropical 72 at 4am, to a comfy 59 by 7am...a 13 degree drop in just 3 hours!

Temperatures will still reach to 80s today behind the front in southern Minnesota, but it looks like we've seen our last sticky 70 degree dew point for about a week.

Winds whip up:

We're feeling the result of "atmospheric momentum" and "mix-down" today across Minnesota. These abstract weather concepts are producing the wind you feel on your face today.

A strong pressure gradient at between 5 and 10 thousand feet today will "mix-down" to the surface as the sun heats the lower atmosphere today. This "transfer of atmospheric momentum" will result in gusty NW winds between 15 and 30 mph at times.

Expect white caps on Minnesota lakes today. In fact, the strong persistent NW winds could produce some big waves on the larger lakes today. How about some 3-5 footers on the SE shore of Mille Lacs?

Wind and waves building on Mille Lacs already this morning.

Be careful on the bigger lakes today!

Category 3 Irene: A growing threat to NYC & Boston?

Speaking of wind, Irene has intensified as expected into a Category 3 hurricane.

Accuweather IR satellite image shows a clear "eye" in Irene Wednesday morning.

Here are the stats as of Wednesday morning as Irene lashes the Bahamas.

BULLETIN
HURRICANE IRENE INTERMEDIATE ADVISORY NUMBER 16A
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092011
800 AM EDT WED AUG 24 2011

SUMMARY OF 800 AM EDT...1200 UTC...INFORMATION
----------------------------------------------
LOCATION...21.9N 73.3W
ABOUT 55 MI...85 KM SE OF ACKLINS ISLAND BAHAMAS
ABOUT 335 MI...540 KM SE OF NASSAU
MAXIMUM SUSTAINED WINDS...115 MPH...185 KM/H
PRESENT MOVEMENT...WNW OR 300 DEGREES AT 9 MPH...15 KM/H
MINIMUM CENTRAL PRESSURE...957 MB...28.26 INCHES

Irene is forecast to reach a peak intensity of 125 mph in the next 48 hours.

The latest model tracks shift Irene to the east again, and indicate the most dangerous center and right side of the hurricane may pass just offshore of North Carolina's Outer Banks. Still I expect to see Jim Cantore getting sand blasted as the storm races by the Outer Banks Sunday.

The suite of models then takes a Category 1 Irene dangerously close to NYC, over the eastern tip of Long Island, and straight into the Boston metro and Cape Cod.

It's still too early to say what kind of damage could result in the major cities of the northeast, but Irene may yet deal a blow to a major metropolitan area.

Stay tuned!

PH

Irene track shifts east; MSP's warm summer numbers

Posted at 9:30 PM on August 23, 2011 by Paul Huttner
Filed under: Hurricanes

A quick update on Hurricane Irene.

BULLETIN
HURRICANE IRENE INTERMEDIATE ADVISORY NUMBER 14A
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092011
800 PM EDT TUE AUG 23 2011

SUMMARY OF 800 PM EDT...0000 UTC...INFORMATION
----------------------------------------------
LOCATION...21.1N 71.8W
ABOUT 50 MI...80 KM WSW OF GRAND TURK ISLAND
ABOUT 90 MI...145 KM E OF GREAT INAGUA ISLAND
MAXIMUM SUSTAINED WINDS...90 MPH...150 KM/H
PRESENT MOVEMENT...WNW OR 295 DEGREES AT 9 MPH...15 KM/H
MINIMUM CENTRAL PRESSURE...969 MB...28.61 INCHES

As I said in my morning post, Irene is slated to intensify and become a major hurricane in the next 24 hours.

The one change worth noting is that Tuesday's forecast model trends are to push Irene further to the east. This may suggest that Irene will not produce a direct hit on the Carolina coast....it could be more of a glancing (but still substantial) blow on the Outer Banks.

Here are the latest spaghetti models.

This potentially good news for places like Myrtle Beach and Charleston may be bad news for News for Long Island and Cape Cod. Irene may spend more time over open ocean, and that could mean a potentially stronger hurricane if the tracks near New York City and Boston verify.

After Tuesday's rare earthquake on the East Coast, some areas may feel the forces of an earthquake and hurricane in the same week for the first time ever!

Stay tuned!

Warm summer, but no 90s so far in August?

Southern Minnesota flirted with 90 today, with plenty of humidity to boot. Believe it or not MSP and much of Minnesota has not recorded a 90 degree temperatures so far in August!

14 days at or above 90 at MSP Airport so far in 2011.

13 days on average at or above 90 each year at MSP.

25 days this summer with highs between 85 and 89 degrees at MSP this summer!

40 days at or above 85 degrees at MSP in 2011.

+1.1 degrees vs. average temps at MSP in June

+ 5.6 degrees vs. average in July

+2.2 degrees so far in August

+3 degrees vs. average at MSP sumemr of 2011!

It feels like it's been warm this summer, and the numbers support that.

With just one week left in "meteorological summer" we are running about 3 degrees warmer than average for the summer of 2011 in the Twin Cities and much of Minnesota.

There's been plenty of beach weather, and after a chilly start, lake water temperatures finally warmed up into the lower 80s by mid-July in the south and well into the 70s up north.

To me the most interesting stat is the number of 90 degree days this year.

MSP Airport has recorded 14 days of 90 degree pus heat. That's only one above the annual average of 13 days. But we've had 6 days with a high of 89 degrees, and 25 days with highs between 85 and 89 degrees!

Add up all the days above 85 degrees (very warm by any standards) and we've (enjoyed?) a full 40 days at or above 85 degrees this summer.

Not bad!

"Fresh Front" Ahead Wednesday:

After a fairly sweaty Tuesday PM & night, a cool front will sweep away the hot humid air mass which made a brief cameo in Minnesota.

Look for a fresh northwest breeze building Wednesday.

Fresh gusty northwest winds Wednesday afternoon!

It will still be warm and feel like summer with highs in the 80s, but dew points will plunge into the 50s Wednesday afternoon and evening! It will fell downright comfy by sunset Wednesday night.

That sunset is now at 8:04pm, which is a full hour earlier (gulp) than in late June! You can see the boats on area lakes heading for shore about 90 minutes earlier than two months ago.

"Fair" Forecast: Good to great

Thursday's weather may be just "perfect" for the opening of the Minnesota State Fair. A weak bubble of high pressure overhead will bring all day sunshine, highs in the low 80s and comfy humidity with dew points in the upper 50s.

Does it get any better?

In fact the first few days of the fair may be ideal. It looks like the best shot of a thundery rainy day will come Sunday.

Here's the NWS version of the forecast.

Thursday: Sunny, with a high near 83. Northwest wind at 7 mph becoming southwest.

Thursday Night: Mostly clear, with a low around 64.

Friday: A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 83.

Friday Night: A slight chance of showers and thunderstorms. Partly cloudy, with a low around 65.

Saturday: Mostly sunny, with a high near 78.

Saturday Night: A slight chance of showers and thunderstorms. Partly cloudy, with a low around 62.

Sunday: A slight chance of showers and thunderstorms. Partly sunny, with a high near 77. (Note: I would put the rain chances higher for Sunday...more like 50-60%)

Monday: A slight chance of showers and thunderstorms. Mostly sunny, with a high near 74.

Tuesday: Partly sunny, with a high near 75.

It's always hard to believe State Fair time is here this week. It seems to come up fast every year, but also just at the point where maybe...just maybe, you think we've had a long enough summer that we can lazily drift into fall next month,

I'm convinced the Minnesota State Fair is the perfect "psychological tonic" for Minnesotans to begin the slow transition into school and the fall season.

We stroll lazily around the Fair, soak up the last real doses of summer, enjoy the foods, sights, smells and sounds. We savor the summer that was, while we convince ourselves "it's been a great summer" and we tell ourselves we are realy looking forward to fall.

By the way, if you enjoy the wistful and nostalgic feelings some seem to get this time of year I highly recommend watching an old Twilight Zone episode "Walking Distance."

It's a great study on how we all would like to go back to the summers of our youth at some point. It is widely considered to be one of the best Twilight Zone episodes ever produced.

Another feeling I get this time of year a powerful sense of transition. I also recommend watching American Graffiti sometime in the next two weeks. The Lucas classic perfectly captures the seasonal and life transitions that seem to occur as summer eases into September.

But I digress.

PH

"Major" Hurricane Irene to 135 mph? MN: Heat builds today

Posted at 8:59 AM on August 23, 2011 by Paul Huttner
Filed under: Hurricanes

It looks like Hurricane Irene is ready to go into "beast mode"

All indications point ot rapid intensification of Irene over the next 24 to 48 hours. Irene will likely become an even more powerful Category 3 storm with 120 mph winds within 24 hours.

WSI loop of Irene Tuesday.

Here are the stats on Irene as of Tuesday morning:

BULLETIN
HURRICANE IRENE INTERMEDIATE ADVISORY NUMBER 12A
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092011
800 AM EDT TUE AUG 23 2011

SUMMARY OF 800 AM EDT...1200 UTC...INFORMATION
----------------------------------------------
LOCATION...20.6N 70.6W
ABOUT 70 MI...110 KM SSE OF GRAND TURK ISLAND
ABOUT 55 MI...90 KM N OF PUERTO PLATA DOMINICAN REPUBLIC
MAXIMUM SUSTAINED WINDS...100 MPH...160 KM/H
PRESENT MOVEMENT...WNW OR 295 DEGREES AT 10 MPH...17 KM/H
MINIMUM CENTRAL PRESSURE...978 MB...28.88 INCHES

Irene builds near Grand Turk Island Tuesday. (Image courtesy Accuweather)

Next 24 to 48 hours:

Irene is expected be in a favorable environment for rapid intensification over the next 2 days.

1) Irene is headed over mostly open water.

2) Surface waters are very warm (85 degrees+) along Irene's projected path.

3) Irene is expected to encounter very little or no wind shear in the next 48 hours.

All of these factors will allow Irene to strengthen rapidly. Satellite images show Irene is currently compact and concentric, and is likely to grow into a larger than average hurricane according to NHC.

"HURRICANE IRENE DISCUSSION NUMBER 12
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092011
500 AM EDT TUE AUG 23 2011

IRENE IS FORECAST TO REMAIN IN A RELATIVELY LOW VERTICAL WIND SHEAR
ENVIRONMENT AND OVER SSTS NEAR 30C. THAT COMBINATION...ALONG WITH
EXPANDING OUTFLOW IN ALL QUADRANTS...SHOULD ALLOW FOR IRENE TO
BECOME A MAJOR HURRICANE WITHIN THE NEXT 24 HOURS ONCE THE CYCLONE
CLEARS THE EFFECTS OF HISPANIOLA...AND PROBABLY MAINTAIN MAJOR
HURRICANE STATUS THROUGHOUT THE REMAINDER OF THE 5-DAY FORECAST
PERIOD. THE INTENSITY FORECAST IS SIMILAR TO THE PREVIOUS ADVISORY
AND CLOSELY FOLLOWS A BLEND OF THE HWRF AND GFDL MODEL INTENSITY
FORECASTS...AND CONVERSION OF THE SURFACE PRESSURES DEPICTED IN THE
GFS AND ECMWF MODELS.

IRENE IS FORECAST TO BECOME A LARGER THAN AVERAGE HURRICANE. IT IS
IMPORTANT TO REMIND USERS NOT TO FOCUS ON THE EXACT FORECAST
TRACK...ESPECIALLY AT DAYS 4 AND 5...SINCE THE MOST RECENT 5-YEAR
AVERAGE ERRORS AT THOSE FORECAST TIMES ARE 200 AND 250 MILES...
RESPECTIVELY.

FORECAST POSITIONS AND MAX WINDS

INIT 23/0900Z 20.3N 70.1W 85 KT 100 MPH
12H 23/1800Z 20.9N 71.5W 95 KT 110 MPH
24H 24/0600Z 21.7N 73.3W 105 KT 120 MPH
36H 24/1800Z 22.9N 74.9W 110 KT 125 MPH
48H 25/0600Z 24.3N 76.2W 110 KT 125 MPH
72H 26/0600Z 28.0N 78.0W 115 KT 135 MPH
96H 27/0600Z 31.5N 78.3W 105 KT 120 MPH
120H 28/0600Z 35.0N 78.0W 100 KT 115 MPH...INLAND"

Track Forecast:

The most probable landfall scenario (and the official NHC track) crashes a powerful 120 mph Category 3 hurricane into the North Carolina coast near Wilmington and Cape Fear late Saturday or Sunday.

Official NHC track forecast.

Overall the suite of computer forecast models are in much tighter agreement today.

There is still some divergence as we head to the weekend. A few of the models suggest a track that could shift Irene to pass east of the Outer Banks.

Orcasystems track & intensity graphics

USA Impacts:

The sheer size of Irene may mean that Florida's east coast still gets brushed with strong tropical force or even hurricane force gusts, heavy surf and dangerous rip tides.

After the potential devastating landfall in the Carolinas, the northeast will have to be on alert for Irene.

Bottom Line: Irene is about to become a major and extremely dangerous hurricane.

Stay tuned for updates on track & intensity.

Minnesota: Stormy, hot Tuesday, Fresh front Wednesday

It was a mostly sleepless night at the weather lab and for many Minnesotans. When you're a weather guy, it's hard to sleep through thunder & lightning. Yes, I find myself glued to the radar screen at 3am sometimes. Today was one of those mornings.

A strong MCS raced southeast along I-94 from North Dakota overnight. The complex was in decay mode by the time it hit the metro around 5am.

The overnight storms were well forecast, and did leave a few severe weather reports in their wake.

MPX: 5 S Monticello [Wright Co, MN] law enforcement reports TSTM WND DMG at 05:15 AM CDT -- trees down on power lines.power out.

MPX: Buffalo [Wright Co, MN] mesonet reports TSTM WND GST of M63 MPH at 04:59 AM CDT -- buffalo airport awos 0959z.

The sun is peeking out at the weather lab this morning, and PM sun should help boost temps to near 90 in much of southern Minnesota this afternoon.

The heat won't last this time, a fresh cool front will spill drier Canadian air south Wednesday and Thursday.

Thursday's Fair opener still looks grand. Look for plenty of sun and a high in the low 80s.

Does it get any better for corn dogs & root beer?

PH

Forecast: "Major" Hurricane Irene; MN: Overnight Thunder?

Posted at 5:29 PM on August 22, 2011 by Paul Huttner
Filed under: Hurricanes

Hurricane Irene is gathering steam and ready to roll.

All systems appear to be "go" for Irene, the Atlantic season's first hurricane, to morph & mutate into the first major hurricane of 2011.

Current Conditions:

Irene beat up on Puerto Rico Sunday & early Monday. By late Monday Hurricane Irene is a Category 1 hurricane on the Saffir- Simpson Hurricane Intensity Scale with 80 mph winds.

BULLETIN
HURRICANE IRENE ADVISORY NUMBER 9
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092011
500 PM AST MON AUG 22 2011

SUMMARY OF 500 PM AST...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...19.5N 68.6W
ABOUT 215 MI...340 KM SE OF GRAND TURK ISLAND
ABOUT 65 MI...100 KM NNW OF PUNTA CANA DOMINICAN REPUBLIC
MAXIMUM SUSTAINED WINDS...80 MPH...130 KM/H
PRESENT MOVEMENT...WNW OR 295 DEGREES AT 13 MPH...20 KM/H
MINIMUM CENTRAL PRESSURE...988 MB...29.18 INCHES

Visible satellite image shows Irene growing north of Hispaniola.
(Click to enalrge for easily readable images)

Track Forecast:

All the various computer model tracks agree on two things during the next 48 hours.

1) Irene is headed for the Bahamas.

2) Irene is going track over mostly warm, open waters and grow stronger.

The "official" NHC track takes Irene toward the South Carolina coast Saturday as a major hurricane.

After 48 hours larger differences in tracks emerge, but the consensus is that Irene will recurve northward and may either make landfall in the USA or parallel the coast for a while.

Keep in mind that the 5 year average error for hurricane track forecasts is about 200 miles 4 days out.

The latest model packages have shown a general trend to shift the track slightly east.

This may be good news for south Florida, if Irene is able to track further offshore.

This may also increase the chances of a direct hit on the Carolinas, and more time over open ocean and a warm Gulf Stream may cause Irene to intensify and explode into a major hurricane.

Intensity Forecast:

Irene's probable track over warm open waters and the super warm Gulf Stream current look favorable for turning Irene into a large, well organized major (Category 3 or higher) hurricane in the next 72 hours.

From the NHC discussion....

"ALL OF THE INGREDIENTS ARE CONDUCIVE FOR IRENE TO INTENSIFY OVER THE NEXT FEW DAYS. THE OFFICIAL FORECAST CALLS FOR IRENE TO BECOME A STRONG CATEGORY 2 OR CATEGORY 3 HURRICANE ON THE SAFFIR-SIMPSON HURRICANE WIND SCALE AS IRENE MOVES ACROSS THE CENTRAL AND NORTHWESTERN BAHAMAS. IN FACT...BOTH THE GFS AND THE ECMWF GLOBAL MODELS INSIST ON MAKING IRENE A LARGE AND STRONG HURRICANE WITH MINIMUM PRESSURES AROUND 945 MB AND 952 MB...RESPECTIVELY."

Official NHC intensity forecast surges Irene to 115 mph by Thursday, a major Category 3 storm. The GFS model, (which appears to have successfully predicted the notion of development and approximate location of Irene somewhere off the Florida coast 10 days in advance!) drops Irene's central pressure to 945 millibars, which would make Irene a borderline Category 4 Hurricane!

FORECAST POSITIONS AND MAX WINDS

INIT 22/2100Z 19.5N 68.6W 70 KT 80 MPH
12H 23/0600Z 20.1N 70.2W 80 KT 90 MPH
24H 23/1800Z 20.8N 72.5W 85 KT 100 MPH
36H 24/0600Z 21.5N 74.0W 90 KT 105 MPH
48H 24/1800Z 23.0N 75.5W 95 KT 110 MPH
72H 25/1800Z 26.0N 78.0W 100 KT 115 MPH
96H 26/1800Z 29.5N 79.0W 100 KT 115 MPH
120H 27/1800Z 34.0N 79.0W 80 KT 90 MPH...INLAND

Either way, all indications are that Irene is going to be a nasty major hurricane by Thursday. Irene could reach Category 3, or possible Category 4 intensity by then.

Keep in mind that hurricane track forecasts are generally more accurate and reliable than hurricane intensity forecasts. If Irene encounters favorable (low) wind shear over the super warm Gulf Stream current off the Florida Coast, she may get a "super charged" shot of energy and undergo rapid intensification Thursday.

USA Threats?

South Florida may be breathing slightly easier today with the eastward shift of the model consensus, but Florida is not out of the woods yet for several reasons.

-The NAM model still predicts a direct hit near Miami late Thursday night or Friday morning.

-Irene will grow in size and intensity, and even if the center tracks 100+ miles offshore, the storm may be large enough and powerful enough to do damage on Florida's east coast, especially in northern Florida near Jacksonville.

The official NHC track, and the model consensus puts the Carolinas most at risk for a direct strike from a major Category 3 hurricane Saturday.

After that there are also scary scenarios for Washington D.C., New York City and Long Island, and even Boston and Cape Cod.

Stay tuned for the latest track and intensity shifts. The next 48 hours will be critical in telling just how strong Irene will get, and where she may strike!

Minnesota Forecast: Possible MCS overnight & early Tuesday?

It could get loud & wet in parts of Minnesota overnight & early Tuesday.

A hot, sticky tropical air mass may greet Minnesotans with some heavy thunderstorms and a possible MCS overnight into Tuesday morning. Call it a "sunrise surprise" in some areas, but be ready for some potentially big storms to fire in the overnight hours and rumble through early Tuesday morning.

The storms have the potential to pack high winds, hail and heavy rainfall.

NAM model paints some .50" to 1"+ rainfall totals near the metro Tuesday morning.

SPC has placed much of Minnesota under a slight risk for severe weather.

Don't be "sunrise surprised" if you get shook out of bed by a loud crack of thunder early Tuesday morning!

PH

Dangerous Irene to slam SE USA? MN: Heat, rain & "Fair" weather week

Posted at 8:55 AM on August 22, 2011 by Paul Huttner
Filed under: Hurricanes

Get ready for non-stop news coverage of what could be the first hurricane to strike the USA in nearly 3 years. It's been 1073 days since Hurricane Ike slammed into Texas.

They'll be battening down the hatches from Florida to the Carolina's this week as what could become "major" Hurricane Irene moves toward the U.S. coast.

Irene lashed Puerto Rico as a tropical storm Sunday.

Radar loop shows swirling center as Irene lashes Puerto Rico Sunday.

Irene is now Hurricane Irene as the system moves over open water north of Hispaniola. (Click on images to enlarge)

WSI IR satellite loop shows Irene organizing over open water.

So where is Irene headed?

Let's start today with the "official" NHC track. NHC forecasts Hurricane Irene to graze the east side of Florida Friday, with a potential landfall near the Florida-Georgia border Saturday. Keep in mind that the 5 year average track error for hurricanes is 200-250 miles 4-5 days out.

Many models indicate the track may be shifted further east. The suite of hurricane "spaghetti models" clusters Irene's track east of Florida with landfall somewhere in the Carolinas this weekend.

If that track verifies, what could be good news for Florida may be very bad news for the Carolinas and the east coast of the USA. More time over the open, warm waters of the Gulf Stream may "flare" Irene into a monster. Rapid intensification is possible over the super charged Gulf Stream, and a Category 3 hurricane with winds over 115mph is possible as it approaches land.

Check out the intensity forecasts for Irene. A few of the models intensify Irene to a Category 3 hurricane with winds of 111 mph+!

As you can see there is still great variabiliy in track and intensity forecasts for Irene. It is still way to early to be married to any one track scenario. People from Florida to the Carolinas (and beyond) should be making hurricane preparations today and tomorrow.

East Coast Hurricane nightmare track?

Many of the models are suggesting a track for Irene that could bring the storm right along the East Coast of the USA. This could leave the eastern side of the storm out over open water, as the storm rakes the east coast from Washington, D.C. through New York & Long Island all the way to Boston.

If that happens, even a Category 1 Irene may become a devastating storm affecting millions. Damage from Irene could rise into the billions.

All of this of course depends on the exact track of Irene. There could be a merciful shift east that would keep the most destructive part of the hurricane out over open water, but at this point that does not look like the most likely solution.

Stay tuned as we track Irene this week. This has the potential to be a major weather disaster for the eastern USA.

Minnesota: Amazon Jungle heat, thunder & a perfect start to the Fair this week?

If you like variety, you may enjoy our forecast. It looks like we may see a little bit of everything this week in Minnesota.
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Monday: Can you dream up a more perfect summer day?

Plenty of sun today. Highs in the lower 80s. More humid by late afternoon. Wind SSW increasing to 10-20 mph late.

Overnght & early Tuesday: a 40% chance of thunderstorms after midnight into Tuesday AM. Some could be heavy.

Tuesday Afternoon: Barbaric heat & humidity. Hazy sun, intensely hot & humid. High near 92-95 in the south. Dew points 75+. Heat index could reach 103 in some areas by late Tuesday afternoon.

Wednesday: Relief! Cool front brings fresh NW breezes at 10-20 mph. High near 85, but much less humid with dew points falling into the upper 50s late.

Thursday: State Fair Opening Day! Weather perfection? Sunny with comfortable humidity and a high near 83. Light west winds. Wow!

Friday: Mixed sun & clouds. Warm & more humid. Thunder threat? High 85.

Stay tuned as we track the two major weather stories this week...Hurricane Irene and State Fair weather!

PH

Pop up T-Showers; Florida Hurricane threat; Double-Dip La Nina?

Posted at 8:47 AM on August 18, 2011 by Paul Huttner (1 Comments)
Filed under: Hurricanes, La Nina

Fickle Thursday:

Look for a few isolated "pop-up" showers & T-showers today around Minnesota & the Upper Midwest.

-Latest Twin Cities radar loop

What meteorologists refer to as a "weak synoptic pattern" is providing enough instability to generate the isolated T-Showers. Weak synoptic patterns are defined by the lack of a major focal point to generate storms...like a strong cold front or big low pressure system does.

The result is a higher degree of difficulty forecasting exact timing and location of storms.

There's just enough instability today that SPC has much of Minnesota under a slight risk for severe weather.

I don't expect a big widespread severe weather outbreak today, but one or two storms could approach severe limits.

Florida: Keeping a wary eye on the tropical Atlantic

Again, it's too early to issue any reliable hurricane forecasts a week in advance. But it's not too early to start paying attention when the same model insists on placing a (potentially strong?) hurricane somewhere near Florida late next week.

For the 3rd day in a row, the NCEP GFS model is developing a hurricane and tracking it westward to a position near south Florida sometime late next week.

There's a lot of open water and atmosphere between the tropical wave, which is still in the eastern Atlantic... and Florida.

Here's the latest from NHC.

A LARGE TROPICAL WAVE LOCATED ABOUT 875 MILES WEST OF THE CAPE VERDE ISLANDS CONTINUES TO PRODUCE LIMITED SHOWER ACTIVITY. SIGNIFICANT DEVELOPMENT IS NOT LIKELY DURING THE NEXT COUPLE OF DAYS. HOWEVER...ENVIRONMENTAL CONDITIONS COULD BECOME MORE CONDUCIVE FOR DEVELOPMENT AFTER THAT TIME. THIS SYSTEM HAS A LOW CHANCE...10 PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS AS IT MOVES WESTWARD AT 15 TO 20 MPH.

Anything could happen in the next week, but if I lived in Florida I would have my "pre hurricane" action plan in full gear and be readying thing just in case this pans out next week. That's a good idea anyway during late August in the southeast USA.

Stay tuned.

"Double-Dip" La Nina?

It doesn't happen often, but there are signs that we may see a rare "double-dip" La Nina again next winter.

La Nina years (cold water in tropical Pacific) are usually separated by an El Nino episode (warm water) in between.

But every so often (2008-2009 & the mid 1970s) a La Nina will fade to neutral, only to regenerate again the next year.

Historical El Nino Southern Oscillation. La Nina episodes in blue, El Nino in red.

There are signs La Nina could regenerate next winter, and CPC has issued another "La Nina Watch."

The various climate models are split on what will happen next winter. Some say a weak El Nino, some are "ENSO neutral" and some say La Nina will return.

At this point I'd say it's a coin flip, but we may know more when the next ENSO advisories are issued in September and October.

Last winter's relatively strong La Nina may be the reason we saw heavy to record snowfall, and a cold spring. But all La Nina episodes are not equal in terms of the weather patterns they produce. I'd say it's unlikely we'll see another 86" of snowfall next winter in the metro, but I suppose anything is possible.

Again...stay tuned!

PH

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Tropical trouble? Seattle public radio meteorologist finds new home

Posted at 5:18 PM on August 17, 2011 by Paul Huttner
Filed under: Hurricanes

It's the time of year when forecasters at NHC watch every little tropical wave in the Atlantic with a wary eye.

Today, there are two main areas of interest in the Atlantic. One may threaten Central America. The other could be a threat to the southeast USA late next week.

93L

So called low pressure system 93L is churning in the Caribbean Sea south of Hispaniola. The system is showing some signs of circulation, and hurricane hunter aircraft have been dispatched to investigate the potential for low level organization.

Weather Underground hurricane guru Jeff Masters has the write up. "Caribbean disturbance 93L, A westward-moving tropical wave in the Central Caribbean a few hundred miles south of Hispaniola, Invest 93L, has increased in organization overnight, building up a modest amount of heavy thunderstorms. Low-level spiral bands have begun to form on all sides of the storm this morning. There are currently no signs of a surface circulation, though there is plenty of large-scale rotation apparent on satellite imagery. Dry air surrounds 93L and has infiltrated the center of the disturbance, giving 93L a doughnut-like appearance. However, the disturbance is steadily moistening its environment and is under low wind shear of 5 - 10 knots, so this dry air should gradually mix out today and allow 93L to continue to organize. There is a hurricane hunter mission scheduled for this afternoon at 2pm EDT to see if a tropical depression is forming.

93L will bring heavy rain showers to southern Haiti this afternoon and to Jamaica tonight. By Thursday, 93L's forward motion will slow to 10 - 15 mph, and the storm will bring heavy rains to Northern Honduras and Northeast Nicaragua. These rains will spread to Belize and Mexico's Yucatan Peninsula by Saturday. The latest SHIPS model forecast shows wind shear remaining in the low range and the atmosphere steadily moistening as 93L enters the Western Caribbean on Thursday. All of the models agree that the ridge of high pressure steering 93L to the west will remain strong, forcing the storm into a landfall Friday in Northeast Nicaragua or Northeast Honduras. It is possible that 93L will have time to intensify into a Category 1 hurricane before then, though landfall as a tropical storm would be more likely, given the dry air that 93L needs to overcome. Regardless of development, the storm will bring very heavy rains of 4 - 8 inches or more to Nicaragua and Honduras. These rains are likely to cause dangerous flash flooding and mudslides. NHC gave 93L a 30% chance of developing into a tropical depression by Friday morning in their 8am outlook; I'd put these odds at 50% now, given the continued increase in organization seen on satellite images."

Hurricane modles are tracking the system west into Central America or southern Mexico.

Florida threat next week?

The second tropical wave near the Cape Verde Islands in the eastern Atlantic has the potential to be an eventual threat to the southeast USA late next week.

As I wrote Wednesday morning, the GFS insists on bringing a hurricane to somewhere near the southeast USA by next Thursday or Friday. Various runs of the GFS have placed the system near Florida, then into the Gulf or curving north into Georgia.

Again, Jeff Masters has the write up. "A tropical wave near 14°N 34°W, about 500 miles west-southwest of the Cape Verde Islands off the coast of Africa, is moving westward near 15 - 20 mph. This wave has little heavy thunderstorm activity associated with it due to dry air, but an impressive amount of large-scale spin is obvious in visible satellite loops. This wave is expected to arrive in the Lesser Antilles Islands by Saturday. Three of our four reliable models for predicting tropical storm genesis predict that this wave could develop into a tropical depression sometime Friday through Sunday. A west-northwest track through the Northeast Caribbean bringing the storm near Puerto Rico by Sunday or Monday is favored by most of the models."

If you read between the lines and follow that track, you can see the logical extension (and GFS solution) is that a hurricane may approach the southeast USA late next week.

Stay tuned.

Seattle Public Radio meteorologist booted from one station, finds a new home.

I've never met Cliff Mass, but I've read some of his excellent work and he's well respected in the Pacific Northwest and nationally as a researcher. The UW Professor has had a weekly radio gig on public radio in Seattle of many years. Think Mark Seeley in Seattle.

It appears that Dr. Mass has recently strayed from talking about weather and climate issues into expounding on other topics of interest for him.

I don't have a whole lot of comment here except to say that if I decided to take on other topics outside of weather or climate during my MPR weather chats, I'm pretty sure I'd be invited to pay a visit to my managers office in a hurry. My role here is to talk about weather and climate, and any related topics that may be of interest to MPR listeners. It's just how the biz works...you fill your slot and that's that. If they want somebody to talk about politics or some other topic, there are plenty more capable and experienced than me ready to do that.

Here are some details on the Cliff Mass dust up in Seattle.

Outlook now sunny for outspoken pubradio weatherman in Puget Sound

"Cliff Mass, the colorful local weather guy whose non-weather opinions got him booted off Seattle's news channel KUOW in May, soon will have a regular spot on jazz station KPLU in Tacoma, according to the Seattle Times. Mass, a University of Washington professor of atmospheric sciences, was featured weekly on KUOW's morning show, Weekday, to discuss weather. But sometimes he would veer off onto other subjects, including a controversy over which textbooks to use in local schools. Station management asked him to stop; he refused. And so Steve Scher, host and executive producer of Weekday, removed Mass from the unpaid spot. In a letter posted for listeners, Scher wrote, "I do not want the weather segment to become an opinion and views segment."

"It'll be strictly weather," Mass says."

The perspective from KUOW here.

"When Cliff Mass signed on 15 years ago to be a regular Friday guest on the show Weekday, he told the producers he wanted to do more than just give the weekend forecast. He wanted to talk about science as well.

I'm Deborah Wang, KUOW News."

PH

MN: Taste of fall ahead? GFS: Florida hurricane late next week?

Posted at 8:41 AM on August 17, 2011 by Paul Huttner
Filed under: Fall, Flooding, Hurricanes

The weather maps are looking a little scary in the weather lab this morning.

Last night's north metro flash flood dumped 2" to 3"+ rain totals in the north metro. Some rainfall reports below, including nearly a month's worth of rain in Roseville!

MPX: 5 Nw Roseville [Anoka Co, MN] nws employee reports HEAVY RAIN of M3.21 INCH at 11:00 PM CDT -- heavy rain fell during the evening on tuesday...august 16.

MPX: Wsw Waverly [Wright Co, MN] trained spotter reports HEAVY RAIN of M2.10 INCH at 06:43 PM CDT --

EAU : EAU CLAIRE WI : 83 / 65 / 0.85
MSP : MINNEAPOLIS MN : 84 / 62 / 1.42
STC : ST CLOUD MN : 80 / 54 / 1.66
AXN : ALEXANDRIA MN : 77 / 56 / 0.72
MIC : CRYSTAL MN : 84 / 59 / 2.07
FCM : FLYING CLOUD MN : 83 / 62 / 0.14
RWF : REDWOOD FALLS MN : 79 / 55 / T
STP : ST PAUL MN : 84 / 62 / 1.01

NEXRAD storm total rainfall paints heavy 2" to 3" rainfall totals from Tuesday night in the north Metro.

The deluge put the Twin Cities into the plus category for rainfall in August. MSP Airport has picked up 2.87" this month, and that's .52" above average for the month to date.

Signs of fall ahead?

I know...don't shoot me I'm just the messenger!

We really shouldn't be surprised to see some "blue lines" on the weather map in late August. We're not talking about a headlong launch into fall like weather just yet...but the GFS is showing signs of cooler air pooling up in Canada in the next 7-14 days.

There's still plenty of warm summer like weather ahead as we move into State Fair time next week. But there are indications that before Labor Day, we could see some brief "incursions" of cooler air push south into Minnesota.

Highs in the upper 60s and lows in the 40s in late August???

It's too early to write off summer yet, but it is that time of the year when we turn one eye to Canada to see what's coming.

GFS: Florida hurricane late next week?

This one falls under the weather category of "too early to be reliable, but not to pay attention to."

For the past 2 days now the GFS model has been insistent in bringing a hurricane to somewhere near south Florida by late next week. The models have varied in exact location from run to run, but have been consistent in the notion of a (potentially major?) hurricane approaching Florida next Thursday or Friday.

There is a vigorous tropical wave in the Atlantic that bears watching, and the GFS is likely picking up on this and steering it westward next week.

This may be on NHC's radar behind the scenes, but it's just too far in advance to post anything on the potential...at least not yet.

Is this GFS "model fantasy" or a weather fact that we may have to pay attention to in the next week? Don't bet the farm on this one....but keep an eye out for possible headlines concerning the potential for a Florida hurricane in the next week.

PH

Taste of back-to-school weather

Posted at 6:47 AM on August 8, 2011 by Craig Edwards (1 Comments)
Filed under: Forecast models, Hurricanes, Rainfall

A cool front will sweep through the upper Midwest today and tonight bringing the chance for showers and thunderstorms. After the front passes temperatures will fall to readings more typical of late August. Expect brisk northwest winds as well on Tuesday.

Here's the short term RUC model of surface temperatures, pressure pattern and winds for late afternoon. Note the region of sizzling hot temperatures in Kansas andOklahoma, extending into Texas.

Rainfall with this passing cool front will not be overly generous. NOAA's Envirnomental Predication Center paints this graphic of rainfall potential for the next twenty-four hours.

Texas continues to remain in severe drought. Some large areas of the Lone Star State are in exceptional drought.

With regard to tropical storm activity things are quiet for the moment. The peak of the hurricane season is approaching.

Historical record of seasonal tropical storms in the Atlantic from the Hurricane Center.

Early morning temperatures on Wednesday may be the coolest since the Twin Cities dipped below 60 degrees and recorded a low of 58 on June 28th. Check out this forecast for temperatures on Wednesday morning from the WRF model.

On this date in 2010 the Twin Cities Internationl Airport reached 96 degrees to tie the record high for August 8th set in 1894, repeated in 1914. The normal max/min for August 8th in the Twin Cities 82/63.

In case you missed it, Roseau experienced temperatures in the middle 60s for much of Saturday, with early Sunday morning temperatures in the upper 40s.

A rather isolated strong thunderstorm produced golf ball sized hail near Young America in Carver County on Saturday evening.
CE

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Humidity builds; Saturday thunder? Emily takes a nosedive

Posted at 5:00 PM on August 4, 2011 by Paul Huttner
Filed under: Hurricanes

75 degree dew point at 6am Tuesday at MSP Airport

53 degree dew point at 1pm Wednesday

63 degree dew point at 10 am Thursday

After a 22 degree drop in dew point at MSP Airport in 30 hours, you can feel the humidity creeping back up again in Minnesota. Dew points are on the rise through the sticky 60s again, and may reach the tropical 70 degree point by Saturday.

Dew points in the upper 60s & 70s in Iowa are moving back north into Minnesota.

After record humidity this summer you have to wonder if moss is going to start growing on the trees. Is this the Twin Cities or Savannah?

Saturday storm chances:

As moisture increases Friday, a wave of low pressure will skirt the Minnesota-Canadian border Saturday. The system should spawn a few scattered T-Storms as it moves through the Dakotas Friday & Minnesota Saturday.

SPC paints slight risk for severe storms (in yellow) to the west Friday.

Emily fades over Hispaniola:

Once Tropical Storm Emily did a dissapearing act over Hispainola Thursday. The storm's circualtion was never very strong, and it became even more disorganized as it interacted with the highly mountainous island.

Anatomy of a dying Tropical Storm:

Before: Emily looked somewhat better organized on Wednesday.

After: Emily's interaction with mountainous terrain on Hispaniola tears the storm apart.

REMNANTS OF EMILY DISCUSSION NUMBER 13
NWS NATIONAL HURRICANE CENTER MIAMI FL AL052011
500 PM EDT THU AUG 04 2011

SINCE ITS INCEPTION...EMILY NEVER HAD A PARTICULARLY ROBUST
LOW-LEVEL CIRCULATION...AND THE HIGH TERRAIN OF HISPANIOLA
CONTRIBUTED SIGNIFICANTLY TO THE FURTHER DEGENERATION OF THE
CYCLONE TODAY.

SATELLITE...RECONNAISSANCE AIRCRAFT AND SURFACE
OBSERVATIONS INDICATE THAT EMILY NO LONGER HAS A CLOSED
CIRCULATION....AND THE SYSTEM HAS BEEN DOWNGRADED TO A TROUGH OF
LOW PRESSURE WITH ITS AXIS ALONG 75W. THIS WAS A BIG WIN FOR THE
ECMWF GLOBAL MODEL...WHICH NEVER DEVELOPED EMILY AND ALWAYS
FORECAST DISSIPATION NEAR HISPANIOLA.

THERE IS STILL A LARGE AREA OF ORGANIZED DISTURBED WEATHER OVER
HISPANIOLA ASSOCIATED WITH THE REMNANTS OF EMILY. THIS ACTIVITY IS
EXPECTED TO SPREAD TOWARD THE WEST-NORTHWEST AND NORTHWEST OVER
EASTERN CUBA AND THE SOUTHEASTERN BAHAMAS WITH SOME POTENTIAL
FOR REGENERATION IN THE NEXT DAY OR TWO.

EVEN THOUGH EMILY HAS DISSIPATED...HEAVY RAINS REMAIN A THREAT FOR
THE DOMINICAN REPUBLIC AND HAITI.

FORECAST POSITIONS AND MAX WINDS

INIT 04/2100Z 19.0N 75.0W 30 KT 35 MPH
12H 05/0600Z...DISSIPATED

Models track Emily's remains near (over) Florida. The question is will she regenerate?

It remains to be seen if Emily's remains will reorganize as it moves into the Bahamas. For now, the NHC has dropped the advisories for Emily. Emily has already thrown a few curve balls; let's see if she has any more surprises up her sleeve in the coming days.

PH

Minnesota perfect? Will Emily end USA "Hurricane Drought?"

Posted at 8:48 AM on August 4, 2011 by Paul Huttner
Filed under: Hurricanes

That old beer commercial might be right on the mark today. "It doesn't get any better than this?"

Talking to literally thousands of Minnesotans (And Arizonans, and Illinoisans) over the past 20 years of doing weather there are a few constant themes that emerge.

1) Everybody likes different weather. There is not one "perfect weather" ideal fro all.

2) Different weather scenarios benefit people and businesses in different ways.

-Your snowplow guy loves many 3" snows in a season if he chagres by the plow...etc.

-Your electric utility might like a hot spell if they know about it in advance, and don't have to buy expensive extra power on the spot market.

-And farmers like rain on days when car wash owners might not!

There's an old saying..."There is no bad weather, just different kinds of good weather."

That said, I can tell you that if I took a poll of all Minnesotans I think that we might get the vast majority to say that today's weather is pretty close to perfect.

Still I know there will be those who will complain about today's weather. It always amazed me in Arizona how people would complain about the slightest variations from "perfect." It would be sunny, 75 degrees in December and some people complain that "It's a little too windy today" with a 13 mph wind. Human nature I guess?

I hope you can enjoy plenty of sunshine, temperatures in the 80s, and dew points in the lower 60s, with relatively light winds today in Minnesota.

What is your idea of "perfect weather?" Or do you like (or curse the fact) that we have so much variability in our weather in Minnesota?

Hurricane Drought: Will Emily end the string?

Now this is the kind of drought I think we all could get used to!

It's been 3 years since a hurricane has hit the USA. Nasty Hurricane Ike was the last to strike the U.S. back in September 2008...nearly 3 years ago. That makes 1055 days since the last land falling U.S. hurricane.

If no hurricanes hit the United States this year, it would be the longest lull between U.S. hurricane landfalls in recorded history, according to NOAA.

Erratic Emily is keeping forecasters at NHC guessing:

"THE CENTER APPEARS TO BE ON THE MOVE AGAIN...WITH THE INITIAL MOTION
A RATHER UNCERTAIN 285/6. THE DYNAMICAL MODELS CONTINUE TO FORECAST
THAT EMILY SHOULD TURN NORTHWESTWARD WITH AN INCREASE IN FORWARD
SPEED DURING THE NEXT 12-24 HR DUE TO A DEVELOPING WEAKNESS IN THE
SUBTROPICAL RIDGE NEAR AND EAST OF THE FLORIDA PENINSULA.

THE CURRENT FORECAST TRACK AND WIND RADII DO NOT REQUIRE A WATCH FOR SOUTHERN FLORIDA AT THIS TIME. IF EMILY DOES NOT BEGIN ITS
NORTHWESTWARD TURN SOON...A WATCH COULD BE REQUIRED FOR PARTS OF
SOUTHERN FLORIDA LATER TODAY."

The models continue to be split on Emily's eventual path and intensity.

The "official" NHC track seems to favor the eastern solution and creates a close shave for Florida's east coast.

Here's another interesting way to look at Emily. The loop below shows a 72 hour animation of "precipitable water" over the Atlantic. You can see the red areas swirling through the Caribbean as Emily churns westward.

As we say in the weather biz...stay tuned!

La Nina: not dead yet?

The latest ENSO advisory from NOAA's Climate Prediction Center may send a bit of a chill through winter weary Minnesotans. CPC is highlighting the chance that La Nina may hang on this upcoming winter. Too early to bet the farm, and not all La Nina winters are equal in Minnesota.

A safe outlook for winter in Minnesota? Cold with occasional snow.

Enjoying today's weather a little more?

PH

PH

Warmth of August sun, minus the humidity

Posted at 4:30 PM on August 2, 2011 by Craig Edwards
Filed under: Climate, Hurricanes, dew point

I spent a couple hours outdoors this morning and it sure felt warm in the August sunshine. With only a slight cooling breeze it was a blessing to have dew points some twenty degrees lower than Tuesday. The dew point at the Twin Cities International Airport was 74 degrees yesterday and a more comfortable 55 degrees this afternoon.

While the mercury has climbed to ninety degrees or better at MSP this summer season on fourteen days, we are looking at a period out a couple weeks were it may be more to our delight with regard to heat. The average temperature for July in St. Cloud was about 4.5 degrees warmer than normal. The Twin Cities average temp was 5.6 degrees above normal for July 2011.

We have turned the corner for "normal" maximum temperatures in the heart of summer and are slowly creeping down into the lower 80s. By the time we reach August 13th the average high in the Twin Cities is down from 84 to 81 degrees. The 8-14 day outlook from the Climate Prediction Center depicts odds favoring at or somewhat below normal temperatures for the upper Midwest.

Check out the July climate reports for St. Cloud, Minneapolis/St. Paul, Eau Claire and Chanhassen here.

In case you think we had it bad here, and we did with the high dew points, the average maximum temperature for July in Dallas, TX was over 101 degrees. More than 70 percent of Texas is in an exceptional drought. They could use a decaying tropical storm to move inland and dump generous rainfall. That doesn't appear likely soon.

Keeping an eye on Tropical Storm Emily and the computer generated track is the challenge for hurricane forecasters in NOAA's Hurricane Forecast Center.

Here's the link to follow the tropical storm's the reminder of the season. NOAA's Hurricane Center website.

The latest update on the storm named Emily predicts a path that takes it over Haiti with winds of 50 mph and rainfall of over five inches. From the Hurricane Center's most recent statement this afternoon....Tropical Storm EMILY Public Advisory:
RAINFALL...EMILY IS EXPECTED TO PRODUCE TOTAL RAIN ACCUMULATIONS
OF 6 TO 10 INCHES IN PUERTO RICO WITH ISOLATED AMOUNTS OF 12 INCHES.
RAINFALL ACCUMULATIONS OF 6 TO 12 INCHES WITH ISOLATED AMOUNTS OF 20
INCHES ARE POSSIBLE OVER THE DOMINICAN REPUBLIC AND HAITI. THESE
RAINS COULD CAUSE LIFE-THREATENING FLASH FLOODS AND MUD SLIDES.

Track projection as of early this afternoon for Emily.

Always subject to change, but the forecast strength remains below hurricane force of 75 mph winds until early next week.

Enjoy the seasonal temperatures the next couple of days. Overnight temperatures may allow you to shut down the A/C and bring in some outside air.

CE

Late summer arrives; Is "Emily" a threat to Florida?

Posted at 8:25 AM on August 3, 2011 by Paul Huttner (2 Comments)
Filed under: Hurricanes

Welcome to "late" summer.

By one definition, when August arrived this week we stepped into the last third of meteorological summer. The warmest 3 months of the year in Minnesota (meteorological summer) are June, July & August. As much as I hate to say it, we've made the turn and we're just entering the last (hopefully long) lap of summer.

Sunday August 7th is a "cross quarter day," astronomically speaking. This marks the halfway point on the calendar between the summer solstice and the (northern hemisphere) fall equinox. Don't read this if you're faint hearted, but we're actually losing about 18 minutes of daylight a week now! (Gulp)

Want good news?

By most measures, the best 3 months of weather are ahead in Minnesota. It's pretty hard to beat August, September & October in the Upper Midwest...most years anyway.

Free AC: "Fresh front" arrives on schedule

As if on cue, a cool front sailed through Minnesota Tuesday. You can feel it in the air this morning...the big change in air masses. Dew points plunged a full 20 degrees in many areas in 24 hours. That's roughly a 50% drop in atmospheric water vapor, and the reason you feel comfortable and can literally breathe easier today!

Atmospherically speaking we "moved" from the Amazon Jungle to San Diego in 24 hours...not a bad change of atmosphere.

With drier high pressure overhead we may actually string 3 dry days in a row together. That hasn't happened often this summer, and the last time we had 4 dry days in a row in much of Minnesota was the first week of June!

Our next real rain threat moves in Saturday with a shot of scattered T-Storms. Right now Sunday looks gorgeous, with bright sun, temps in the 80s and comfy humidity levels.

Tropical Trouble: Emily gets stronger:

Tropical Storm Emily is making a move toward Hispaniola today.

NOAA satellite IR loop courtesy WSI.

Emily has grown and become better organized in the past 24 hours. The storm is forecast to batter Hispaniola with wind, torrential rains and possible life threatening mudslides.

The interaction with higher terrain on Hispaniola may disrupt Emily, but she is forecast to regain strength over open water after that.

The "consensus" and official NHC track bring then Hurricane Emily to a track east of Florida then recurve her out into the open Atlantic.

There has been some westward shift in some of the hurricane model tracks over the past 24 hours.

Several of the models (about 5 of 15) steer Emily further west, and take the storm on a more westward course that could threaten Florida by this weekend.

About one-third of hurricane forecast models suggest Emily could threaten Florida.

Stay tuned to the progress of Emily. This could be a close call for Florida and the southeast USA.

PH

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Erratic Tropical Storm Don; Deadly USA heat wave persists

Posted at 8:41 AM on July 28, 2011 by Paul Huttner
Filed under: Heat, Hurricanes

So you wanna be a weather forecaster? Even better, a hurricane forecaster?

Tropical storm Don is confounding forecasters at the National Hurricane Center a bit today.

"Don" flares in the Gulf of Mexico Thursday morning.

The storm has been erratic in developing, and Don's future intensity and impacts seem far from certain today. Check out some of the language from the NHC's technical forecast discussion on Don.

"THE INTENSITY FORECAST IS TRICKY. WHILE THE LARGE-SCALE ENVIRONMENT
DOES NOT APPEAR TO HAVE MUCH SHEAR...THE LOW- AND MID-LEVEL CENTERS
ARE NOT WELL-ALIGNED INITIALLY...WHICH WAS APPARENT ON A 2316Z
SSMIS MICROWAVE IMAGE. THE GFS/ECMWF MODELS HAVE A REASONABLE
REPRESENTATION OF THIS INITIAL STRUCTURE AND KEEP THE CENTERS FROM
VERTICALLY STACKING...POSSIBLY WHY THESE MODELS DO NOT SHOW
MUCH INTENSIFICATION. WHILE THE STATISTICALLY MODELS STILL
FORECAST STEADY STRENGTHENING...THE HWRF/GFDL MODELS FORECAST A
SLOW DECLINE. ANOTHER FACTOR TO CONSIDER IS THAT THE SIZE OF DON
MAKES IT SUSCEPTIBLE TO RAPID CHANGES IN STRENGTH...BOTH UP AND
DOWN...THAT ARE NEARLY IMPOSSIBLE TO FORECAST. GIVEN THE REDUCED
ORGANIZATION...THE NHC INTENSITY FORECAST IS LOWERED SOMEWHAT FROM
THE PREVIOUS FORECAST...BUT IS STILL ON THE UPPER END OF THE
GUIDANCE ENVELOPE NEAR A COMPOSITE OF THE SHIPS/LGEM MODELS.

BEST ESTIMATE OF INITIAL MOTION IS 300/9... WITH OVERNIGHT MICROWAVE
IMAGES SUGGESTING THE SMALL CENTER HAS BEEN MOVING ERRATICALLY."

Hurricane forecasting is a tough business, and one of the more difficult specialized areas of meteorology. Weak tropical steering currents, changing ocean temperatures and slight variations in wind shear can mean rapidly fluctuating hurricane intensity.

Hurricane "spaghetti chart" show most models tracking Don toward south Texas.

The models do fairly well with tropical cyclone tracks, but intensity forecasts are much tougher, and less reliable. Let's see what Don has in store in the next 24 hours as it approaches the Texas coast.

Heat Wave 2011: Deadly and persistent

Minnesota has been on the northern edge of the massive heat wave of 2011. We've had our share of hot weather, but nothing compared to places like Kansas, Oklahoma & Texas.

12 days at or above 90 degrees in the metro in 2011

17 days at or above 100 degrees in Topeka, Kansas in 2011!

-The 10 consecutive days of temperatures reaching at least 100 degrees in Topeka this year is tied for Topeka's 7th longest streak of 100 degree temperatures.

Even though we're running a full +5.4 degrees warmer than average in July in the metro, you can see our July heat is almost bearable when compared with the Kansas (and USA) heat wave of 2011.

PH

Excessive Heat Watch; 100 in metro Thursday?

Posted at 9:05 AM on June 29, 2011 by Paul Huttner (1 Comments)
Filed under: Heat, Hurricanes

I hope the A/C is tuned up and ready to go!

Some headlines for the blog today:

-Excessive Heat Watch issued for metro Thursday:

Heat indices over 100 likely...

-Temperature Forecast Techniques:

Just how do meteorologists come up with a "number?"

-Isolated Overnight T-Storm?

Warm front may spark a rumbler overnight.

-1st named storm in Atlantic Hurricane Season:

Tropical Storm Arlene gears up off Mexican Coast.

The heat is on for Thursday:

Get ready for another heat blast.

A strong ridge of high pressure is building overhead Thursday. You'll start to feel the dew point creeping up today, and by Thursday, a full blown "hot front" will push temps to near 100 degrees.

An Excessive Heat Watch is posted by Twin Cities NWS. It will likely be upgraded to a warning Thursday.

URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
414 AM CDT WED JUN 29 2011

...HOT AND HUMID CONDITIONS EXPECTED THURSDAY...

.A HOT AND MUGGY AIR MASS WILL MOVE INTO THE AREA EARLY ON
THURSDAY AND CONTINUE THROUGH FRIDAY MORNING. HIGH TEMPERATURES IN
THE LOWER TO MID 90S ALONG WITH SURGING DEWPOINTS EXPECTED TO
CLIMB WELL INTO THE 70S WILL CREATE HEAT INDEX VALUES OVER 100
DEGREES THURSDAY AFTERNOON AND EARLY EVENING. OVERNIGHT LOW
TEMPERATURES WILL ONLY DROP TO THE MID AND UPPER 70S THURSDAY
NIGHT. THE INNER DOWNTOWN AREAS OF THE METRO WILL BE THE MOST
SUSCEPTIBLE TO THE HOT AND HUMID CONDITIONS.

MNZ060-062-291715-
/O.NEW.KMPX.EH.A.0001.110630T1700Z-110701T1200Z/
HENNEPIN-RAMSEY-
INCLUDING THE CITIES OF...MINNEAPOLIS...ST. PAUL
414 AM CDT WED JUN 29 2011

...EXCESSIVE HEAT WATCH IN EFFECT FROM THURSDAY AFTERNOON THROUGH
FRIDAY MORNING...

THE NATIONAL WEATHER SERVICE IN TWIN CITIES/CHANHASSEN HAS ISSUED
AN EXCESSIVE HEAT WATCH...WHICH IS IN EFFECT FROM THURSDAY
AFTERNOON THROUGH FRIDAY MORNING.

* TEMPERATURE...HIGHS IN THE 90S THURSDAY WITH A HEAT INDEX FROM
100 TO 106.

* IMPACTS...THESE HOT AND HUMID CONDITIONS WILL LEAD TO A
HEIGHTENED RISK OF HEAT RELATED STRESS AND ILLNESSES. THIS WILL
BE ESPECIALLY TRUE FOR THE CENTRAL URBANIZED AREAS OF THE TWIN
CITIES METRO.

How high will it go?

Depending on what you look at, you can get a temperature in the 95 to 100 degree range in most of southern Minnesota by late Thursday afternoon. Combine a dew point in the mid 70s, and heat index could reach 100 to 106 degrees!

Temperature forecast techniques:

Just how do meteorologists come up with tomorrow's high temp? Where does that "number" come from anyway??

There are various forecast techniques used to calculate and predict temperatures.

One old tried and true method is "temperature computation." This is basically what forecast models do these days, but we used to do it by hand back in the "old school" days.

You start with the latest actual temperature...let's say the overnight low was 62 degrees

From 62 degrees, you add the average "diurnal variation" (difference between the average high & low temp on a given day) for the day. This time of year that's 21 degrees for the metro.

So 62 + 21 = 83 degrees if everything is "average."

Now you apply various correction factors. These may include

-Warm or cold advection (warmer or colder air moving in)
-Sun/clouds & sun angle
-Wind
-Precipitation
-Snow cover
-Soil moisture
-Residual heat/cold
-Miscellaneous factors such as smoke, haze etc.
-Lake effect in Great Lakes

After you apply the correction factors (specifics stored deep in the Weather Lab vault) you come up with a number. If you did it right, you should be pretty close to the forecast high or low temp.

850 millibar "mix down" technique:

Another way to shortcut a forecast high temperature is what's called the 850 millibar mix down technique. Basically you use the air temp at 850 millibars (around 5,000 feet above ground level) and "mix it down" to the surface. As the air descends it warms adiabatically. The temperature at 850 mb can be a great indicator of the potential surface temp on a given day.

This technique can work very well on windy sunny days in spring and summer.

Thursday's forecast 850 millibar temps of around 29 degrees Celsius would yield a surface temp of 100 to 105 degrees if everything worked out just right! Relatively high dew points may slow the heat burst, because it takes more energy to heat moist air.

Either way it's going to feel oppressively ht Thursday.

This is Amazon Jungle heat folks.

Rumbler ovenight?

As the heat gurgles north tonight, there is a chance that isolated T-Storms could develop in southern Minnesota and western Wisconsin. Don't be shocked if you hear thunder and rain in the wee hours of Thursday morning.

Arlene kicks off Atlantic Season:

Tropical Strom Arlene is the 1st named storm of the Atlantic Season.

Arlene is forecast to track westward into Mexico Thursday. The primary threat is heavy rainfall.

The details from NHC:

BULLETIN

TROPICAL STORM ARLENE INTERMEDIATE ADVISORY NUMBER 3A
NWS NATIONAL HURRICANE CENTER MIAMI FL AL012011

700 AM CDT WED JUN 29 2011

...ARLENE EXPECTED TO MAKE LANDFALL IN NORTHEASTERN MEXICO EARLY
TOMORROW...

SUMMARY OF 700 AM CDT...1200 UTC...INFORMATION
----------------------------------------------
LOCATION...21.8N 95.2W
ABOUT 175 MI...280 KM E OF TAMPICO MEXICO
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...WNW OR 300 DEGREES AT 8 MPH...13 KM/H
MINIMUM CENTRAL PRESSURE...1002 MB...29.59 INCHES

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A TROPICAL STORM WARNING IS IN EFFECT FOR...
* THE COAST OF NORTHEASTERN MEXICO FROM BARRA DE NAUTLA NORTHWARD TO BAHIA ALGODONES

A TROPICAL STORM WARNING MEANS THAT TROPICAL STORM CONDITIONS ARE
EXPECTED SOMEWHERE WITHIN THE WARNING AREA...IN THIS CASE WITHIN 24
HOURS.

DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 700 AM CDT...1200 UTC...THE CENTER OF TROPICAL STORM ARLENE WAS
LOCATED NEAR LATITUDE 21.8 NORTH...LONGITUDE 95.2 WEST. ARLENE IS
MOVING TOWARD THE WEST-NORTHWEST NEAR 8 MPH...13 KM/H. A TURN
TOWARD THE WEST IS FORECAST LATER TODAY. ON THE FORECAST TRACK...
ARLENE IS EXPECTED TO MAKE LANDFALL ALONG THE NORTHEASTERN COAST OF
MEXICO WITHIN THE WARNING AREA EARLY ON THURSDAY.

MAXIMUM SUSTAINED WINDS ARE NEAR 40 MPH...65 KM/H...WITH HIGHER
GUSTS. SOME STRENGTHENING IS FORECAST UNTIL LANDFALL ON THURSDAY.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 115 MILES...185 KM
FROM THE CENTER.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1002 MB...29.59 INCHES.

HAZARDS AFFECTING LAND
----------------------
RAINFALL...ARLENE IS EXPECTED TO PRODUCE TOTAL RAINFALL
ACCUMULATIONS OF 4 TO 8 INCHES OVER THE MEXICAN STATES OF
TAMAULIPAS...VERACRUZ...AND EASTERN SAN LUIS POTOSI...WITH POSSIBLE
ISOLATED MAXIMUM AMOUNTS OF 15 INCHES OVER MOUNTAINOUS TERRAIN.
THESE RAINS COULD CAUSE LIFE-THREATENING FLASH FLOODS AND
MUDSLIDES.

WIND...TROPICAL STORM CONDITIONS ARE EXPECTED TO REACH THE COAST
WITHIN THE WARNING AREA BY THIS EVENING...WHICH COULD MAKE OUTSIDE
PREPARATIONS DIFFICULT OR DANGEROUS.

STORM SURGE...A STORM SURGE WILL RAISE WATER LEVELS BY AS MUCH AS 1
TO 2 FEET ABOVE NORMAL TIDE LEVELS ALONG THE IMMEDIATE COAST NEAR
AND TO THE NORTH OF WHERE THE CENTER MAKES LANDFALL. NEAR THE
COAST...THE SURGE COULD BE ACCOMPANIED BY LARGE AND DESTRUCTIVE
WAVES.

NEXT ADVISORY
-------------
NEXT COMPLETE ADVISORY...1000 AM CDT.

$$
FORECASTER PASCH/BEVEN

PH

Comment on this post

Showers increase; Hurricane season sends Florida message

Posted at 5:54 PM on June 1, 2011 by Paul Huttner (1 Comments)
Filed under: Hurricanes

Radars will glow with scattered showers and a few T-Storms in southern Minnesota tonight.

Twin Cities radar loop already lighting up with showers early Wednesday evening.

-Latest Twin Cities radar loop

A developing warm front is pushing north from Iowa, and scattered rain & thunder will accompany the front tonight and early Thursday. It appears (according to SPC convective outlooks) the fast moving showers & T-Storms will remain below severe limits overnight.

A slight risk for severe storms favors northern Minnesota and the Dakotas Minnesota Thursday.

Heat and humidity will increase behind the front late Thursday & Friday.

Hurricane season arrives with a message for Florida:

Floridians may have received an early hurricane message today.

Batten down the hatches for Hurricane Season 2011.

The first tropical disturbance of the 2011 season (93L) sailed right over northern Florida Wednesday on the first "official" day of the 2011 Atlantic Hurricane Season.

GOES 1km visible image shows tropical wave as it intensifies over Florida Wednesday.

NHC gives the system a 20% chance of becoming a tropical cyclone in the next 48 hours.

Hurricane expert Jeff Masters at Weather Underground has a great summary of this season's hurricane outlooks and today's systems.

"A very active Atlantic hurricane season is on tap for 2011, according to the seasonal hurricane forecast issued June 1 by Dr. Phil Klotzbach and Dr. Bill Gray of Colorado State University (CSU). The CSU team is calling for 16 named storms, 9 hurricanes, and 5 intense hurricanes, and an Accumulated Cyclone Energy (ACE) 166% of average. Between 1950 - 2000, the average season had 10 named storms, 6 hurricanes, and 2 intense hurricanes. But since 1995, the beginning of an active hurricane period in the Atlantic, we've averaged 14 named storms, 8 hurricanes, and 4 intense hurricanes per year. The new forecast is identical to their April forecast. The forecast calls for a much above-average chance of a major hurricane hitting the U.S., both along the East Coast (48% chance, 31% chance is average) and the Gulf Coast (47% chance, 30% chance is average). The risk of a major hurricane in the Caribbean is also high, at 61% (42% is average.)

4) We are in the midst of a multi-decadal era of major hurricane activity, which began in 1995. Major hurricanes cause 80-85 percent of normalized hurricane damage."

Jeff say 93L is still worth watching as it races into the Gulf.

"Fate of 93L once in the Gulf of Mexico

Since 93L is expected to continue its rapid west-southwest motion at 15 - 20 mph through Thursday, it will cross the Florida Peninsula in about 12 hours and emerge over the Gulf of Mexico early Thursday morning. It is possible that the passage over Florida will greatly disrupt 93L, since it is such a small system. I give a 40% chance that the storm will see its peak strength this afternoon, and not significantly regenerate over the Gulf of Mexico. However, the latest SHIPS model forecast predicts that wind shear will remain low to moderate, 5 - 15 knots, as 93L moves westwards over the Gulf of Mexico Thursday and Friday. SSTs in the Gulf are about 27°C (81°F), 0.5 - 1.0°C above average, and it is possible that 93L could gain enough strength to become Tropical Depression One as it crosses the Gulf. Since 93L will be moving parallel to the coast a short distance offshore, it is difficult to predict where the storm might make a second landfall, since a slight change in heading will make a large difference in landfall location. I don't expect widespread heavy rains from 93L along the Gulf Coast, since the storm is so small, but some locations close to the coast could receive 2 - 4 inches as 93L brushes by. Heavier rains are possible at the eventual landfall location. Since 93L is so small, the computer models are having trouble seeing the system, and are not very helpful forecasting the behavior of the storm over the Gulf of Mexico. The Hurricane Hunters are on call to fly into 93L Thursday afternoon at 2pm EDT, if necessary."

It's not scientific, but after two consecutive years with no hurricane landfalls in the USA my weather "spidey senses" tell me this is going to be a bad year for hurricane damage in the USA.

Let's hope I'm wrong about that one.

PH

Comment on this post

Nicer today; Storm tonight? Heat builds Thursday & Friday

Posted at 7:28 AM on June 1, 2011 by Paul Huttner
Filed under: Heat, Hurricanes, Mosquitoes

Weather headlines for June 1st:

-Wednesday weather improves. More sun, less wind. (but still breezy) High 78. Wind W 10-20 mph eases PM.

-Warm front pushes north tonight. Scattered showers & T-Storms overnight.

-Heat surges north Thursday & Friday. First 90s possible! Muggy dew points near 70?

-Cool front Saturday. Nice weekend with highs near 80 and an isolated T-Storm threat Sunday?

-Meteorological summer begins today! (June 1 - Aug 31)

-Hurricane season begins today. Hurricane outlooks of little value?

-Mosquito Tracker: Find out what's been treated in your neighborhood.

Changeable Forecast:

On a scale of 1 to 10 today might be a 9 in the context of this spring. Look for mainly sunny skies and temps in the mid to upper 70s in southern Minnesota this afternoon.

NWS weather story. (Click all images to enlarge)

Weather station plots over GOES 1km visible satellite image show a west wind again Wednesday morning.

Clouds (and a few showers) may linger in the north with cooler temps in the 60s.

Winds will still blow, but not nearly as strong as the storm force winds of Tuesday. Check out some of Tuesday's observed gusts below. A more complete list from Twin Cities NWS here.

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1216 AM CDT WED JUN 1 2011

...HIGHEST WINDS OBSERVED ON TUESDAY MAY 31ST...

...MINNESOTA...

...ANOKA COUNTY...

1 SW BLAINE (912 FT)(OTHER-MTR) 445 PM MAY 31 34 MPH
2 NW ANOKA (872 FT)(APRSWXNET) 333 PM MAY 31 36 MPH
6 WNW FOREST LAKE (899 FT)(RAWS) 806 PM MAY 31 36 MPH

...CARVER COUNTY...

3 S CARVER (845 FT)(RAWS) 649 PM MAY 31 35 MPH
1 WSW WACONIA (1012 FT)(AWS) 459 PM MAY 31 35 MPH
2 NE LESTER PRAIRIE (938 FT)(MNDOT) 308 PM MAY 31 41 MPH

...CHISAGO COUNTY...

1 NE RUSH CITY (921 FT)(OTHER-MTR) 1034 PM MAY 31 40 MPH

...DAKOTA COUNTY...

2 NE LAKEVILLE (984 FT)(APRSWXNET) 633 PM MAY 31 31 MPH
3 WSW FARMINGTON (958 FT)(OTHER-MTR) 652 PM MAY 31 34 MPH
1 SSW FARMINGTON (944 FT)(APRSWXNET) 712 PM MAY 31 38 MPH
2 NNE EAGAN (820 FT)(OTHER-MTR) 454 PM MAY 31 38 MPH
2 NNW BURNSVILLE (792 FT)(MNDOT) 657 PM MAY 31 41 MPH

...DOUGLAS COUNTY...

4 NNW ALEXANDRIA (1381 FT)(AWS) 604 PM MAY 31 35 MPH
3 SSE ALEXANDRIA (1440 FT)(MNDOT) 757 PM MAY 31 47 MPH
ALEXANDRIA ASOS (1423 FT)(ASOS) 725 PM MAY 31 50 MPH

...HENNEPIN COUNTY...

1 W BROOKLYN PARK (853 FT)(APRSWXNET) 604 PM MAY 31 34 MPH
1 SE MAPLE GROVE (926 FT)(MNDOT) 401 PM MAY 31 35 MPH
1 WSW ROBBINSDALE (2854 FT)(APRSWXNET) 235 PM MAY 31 37 MPH
CRYSTAL ASOS (869 FT)(ASOS) 353 PM MAY 31 38 MPH
FLYING CLOUD ASOS (905 FT)(ASOS) 353 PM MAY 31 38 MPH
1 N MINNEAPOLIS (1066 FT)(APRSWXNET) 217 PM MAY 31 39 MPH
MINNEAPOLIS ASOS (836 FT)(ASOS) 953 PM MAY 31 43 MPH

...ISANTI COUNTY...

2 W CAMBRIDGE (941 FT)(OTHER-MTR) 956 PM MAY 31 40 MPH

...KANABEC COUNTY...

1 E MORA (1013 FT)(OTHER-MTR) 1057 PM MAY 31 39 MPH
1 ENE MORA (1012 FT)(RAWS) 1108 PM MAY 31 42 MPH

...KANDIYOHI COUNTY...

3 WSW PRINSBURG (3504 FT)(APRSWXNET) 1127 AM MAY 31 34 MPH
4 NW WILLMAR (1125 FT)(OTHER-MTR) 315 PM MAY 31 46 MPH

...LAC QUI PARLE COUNTY...

MADISON (1115 FT)(IEM) 427 PM MAY 31 36 MPH
2 SSE MADISON (1082 FT)(OTHER-MTR) 434 PM MAY 31 47 MPH
5 SSW MARIETTA (1169 FT)(MNDOT) 313 PM MAY 31 54 MPH

...MARTIN COUNTY...

2 ENE FAIRMONT (1161 FT)(OTHER-MTR) 415 PM MAY 31 43 MPH

...MCLEOD COUNTY...

1 WSW HUTCHINSON (1051 FT)(APRSWXNET) 503 PM MAY 31 38 MPH
3 E GLENCOE (990 FT)(OTHER-MTR) 515 PM MAY 31 38 MPH
1 SSW HUTCHINSON (1059 FT)(OTHER-MTR) 453 PM MAY 31 45 MPH

...MEEKER COUNTY...

3 S LITCHFIELD (1076 FT)(RAWS) 411 PM MAY 31 41 MPH

...MILLE LACS COUNTY...

1 WSW PRINCETON (977 FT)(OTHER-MTR) 813 PM MAY 31 39 MPH
7 SE ONAMIA (1259 FT)(RAWS) 536 PM MAY 31 42 MPH
8 N MILACA (1195 FT)(MNDOT) 1039 PM MAY 31 43 MPH

...POPE COUNTY...

3 E GLENWOOD (1394 FT)(OTHER-MTR) 453 PM MAY 31 48 MPH
9 SSW STARBUCK (1272 FT)(MNDOT) 631 PM MAY 31 50 MPH

...RAMSEY COUNTY...

1 NW NORTH SAINT PAUL (981 FT)(APRSWXNET) 730 PM MAY 31 31 MPH
2 ESE ROSEVILLE (964 FT)(APRSWXNET) 702 PM MAY 31 33 MPH
SAINT PAUL ASOS (685 FT)(ASOS) 553 PM MAY 31 41 MPH

...REDWOOD COUNTY...

REDWOOD FALLS ASOS (1023 FT)(ASOS) 653 PM MAY 31 44 MPH

...RICE COUNTY...

3 NW FARIBAULT (1056 FT)(OTHER-MTR) 814 PM MAY 31 33 MPH
7 W NORTHFIELD (999 FT)(MNDOT) 315 PM MAY 31 40 MPH
NORTHFIELD (908 FT)(APRSWXNET) 655 PM MAY 31 41 MPH

...SCOTT COUNTY...

1 NNW PRIOR LAKE (938 FT)(APRSWXNET) 145 PM MAY 31 35 MPH
1 WNW JORDAN (826 FT)(APRSWXNET) 204 PM MAY 31 35 MPH
1 NW SHAKOPEE (800 FT)(APRSWXNET) 320 PM MAY 31 36 MPH
2 WSW PRIOR LAKE (970 FT)(APRSWXNET) 216 PM MAY 31 38 MPH

...STEARNS COUNTY...

4 ESE AVON (1200 FT)(APRSWXNET) 418 PM MAY 31 30 MPH
1 E SAINT JOSEPH (1106 FT)(APRSWXNET) 504 PM MAY 31 35 MPH
2 WSW PAYNESVILLE (1181 FT)(OTHER-MTR) 412 PM MAY 31 46 MPH
1 SE RICHMOND (1089 FT)(APRSWXNET) 309 PM MAY 31 47 MPH
2 SE SAUK CENTRE (1241 FT)(OTHER-MTR) 655 PM MAY 31 47 MPH
3 ESE BELGRADE (1249 FT)(MNDOT) 336 PM MAY 31 51 MPH
2 SE SAUK CENTRE (1241 FT)(MNDOT) 347 PM MAY 31 53 MPH

...STEELE COUNTY...

5 NNE ELLENDALE (1192 FT)(MNDOT) 128 PM MAY 31 42 MPH
3 NW OWATONNA (1148 FT)(OTHER-MTR) 535 PM MAY 31 44 MPH

...SWIFT COUNTY...

2 W BENSON (1040 FT)(OTHER-MTR) 212 PM MAY 31 45 MPH
2 NE APPLETON (1020 FT)(OTHER-MTR) 535 PM MAY 31 51 MPH

...WASECA COUNTY...

3 WSW WASECA (1125 FT)(OTHER-MTR) 1240 PM MAY 31 45 MPH

...WASHINGTON COUNTY...

2 N HASTINGS (2270 FT)(APRSWXNET) 255 PM MAY 31 30 MPH
2 E LAKE ELMO (935 FT)(OTHER-MTR) 755 PM MAY 31 41 MPH

...WRIGHT COUNTY...

2 ESE BUFFALO (967 FT)(OTHER-MTR) 534 PM MAY 31 36 MPH
1 ENE MAPLE LAKE (1026 FT)(OTHER-MTR) 513 PM MAY 31 39 MPH
1 SE CLEARWATER (995 FT)(MNDOT) 422 PM MAY 31 44 MPH

...YELLOW MEDICINE COUNTY...

4 SSW GRANITE FALLS (1046 FT)(OTHER-MTR) 213 PM MAY 31 48 MPH
1 NNE CANBY (1191 FT)(OTHER-MTR) 505 PM MAY 31 49 MPH
HANLEY FALLS (1068 FT)(MNDOT) 310 PM MAY 31 49 MPH

...WISCONSIN...

...EAU CLAIRE COUNTY...

1 NW AUGUSTA (970 FT)(RAWS) 405 PM MAY 31 33 MPH
4 WNW FAIRCHILD (984 FT)(APRSWXNET) 603 PM MAY 31 43 MPH

...PIERCE COUNTY...

1 W BAY CITY (784 FT)(OTHER-MTR) 535 PM MAY 31 38 MPH

...POLK COUNTY...

2 ESE SAINT CROIX FALLS (1190 FT)(WIDOT) 818 PM MAY 31 34 MPH
1 NNE FREDERIC (1273 FT)(APRSWXNET) 249 PM MAY 31 41 MPH
1 SSE OSCEOLA (902 FT)(OTHER-MTR) 815 PM MAY 31 41 MPH

...ST. CROIX COUNTY...

5 NW RIVER FALLS (895 FT)(WIDOT) 1013 PM MAY 31 35 MPH
2 N NEW RICHMOND (997 FT)(OTHER-MTR) 235 PM MAY 31 40 MPH
1 WSW HUDSON (740 FT)(WIDOT) 309 PM MAY 31 47 MPH

OBSERVATIONS ARE COLLECTED FROM A VARIETY OF SOURCES WITH VARYING
EQUIPMENT AND EXPOSURES. NOT ALL DATA LISTED IS CONSIDERED OFFICIAL. THE NATIONAL WEATHER SERVICE THANKS ITS PRIVATE AND PUBLIC PARTNERS FOR PROVIDING US WITH THIS DATA.

Next up: Warm front surges back north

A warm front will surge back north into Minnesota late tonight. As it does, "nocturnal" showers and T-Storms will likely develop along the front in southern Minnesota late tonight. Storms should be scattered, and some may contain hail and gusty winds overnight and early Thursday.

NAM model hints at scattered T-Storms overnight.

Heat builds Thursday & Friday:

Behind the front, a hot sticky tropical summer-like air mass will gurgle north into Minnesota. It's going to feel like summer by Thursday afternoon right through Friday.

The hot hazy air mass will give us our first shot at 90-degree + temps by late Thursday or Friday in southern Minnesota.

Models hinting at 90 by Friday!

The air mass will feature tropical humidity levels, with dew points approaching the sultry 70 degree mark late Thursday & Friday!

Dew points near 70 possible.

The best chance for severe storms appears to be in North Dakota and northern Minnesota Thursday, according to SPC.

SPC risk area Thursday.

Weekend cool front:

A cooler front will slide through early Saturday morning. It looks like the front could come through dry, ushering in a fresher air mass for the weekend. There will be a noticeable drop in humidity this weekend as dew points fall into the comfortable 50s.

Overall this could be a very nice early summer-like weekend, with just a chance of an isolated T-Storm Sunday. We'll have to keep an eye on that as the weekend unfolds.

Hurricane season now underway:

It's June 1st, the "official" start of the Atlantic hurricane season.

The various forecasts call for above average number of tropical cyclones in the Atlantic again this year. While seasonal hurricane forecasts get a lot of attention, you have to wonder at times... is there is really any value to seasonal hurricane forecasts?

There are two main reasons why I do not give credibility to seasonal hurricane forecasts.

1) Accuracy: There have been some dismal errors over the past few hurricane seasons.

An excerpt from my post last April:

Posted at 5:01 PM on April 7, 2010 by Paul Huttner
Filed under: Hurricanes

"The annual April seasonal hurricane forecast is out today from the folks at Colorado State University (CSU) led by Phil Klotzbach and Dr. William Gray. After the past few years of iffy forecast results, some are asking; where's the value in producing seasonal hurricane forecasts?

Looking back at the past 5 years of April CSU hurricane forecasts, the accuracy of the CSU seasonal hurricane forecasts is at best mixed. They had a very good year in 2008, but in every other year the forecasts have show an error rate of 33% or higher in either the number of named storms or hurricanes. In addition to badly missing the lowest number of hurricanes since 1997 in the 2009 forecast, CSU's April 2005 forecast of 13 named storms and 7 hurricanes completely missed the notion of the most active Atlantic hurricane season on record. In addition to the devastating Hurricanes Katrina and Rita, 2005 produced a record 28 named storms and 15 hurricanes in the Atlantic. The CSU team under forecast both the number of named storms and hurricanes in 2005 by over 50%."

Not to pick on CSU, NOAA doesn't fare much better. Jeff Masters has the details.

"How accurate are the NOAA seasonal hurricane forecasts?

A talk presented by NHC's Eric Blake at the 2010 29th Annual AMS Conference on Hurricanes and Tropical Meteorology studied the accuracy of NOAA's late May seasonal Atlantic hurricane forecasts, using the mid-point of the range given for the number of named storms, hurricanes, intense hurricanes, and ACE index. Over the past twelve years, a forecast made using climatology was in error, on average, by 3.6 named storms, 2.5 hurricanes, and 1.7 intense hurricanes. NOAA's May forecast was not significantly better than climatology for these quantities, with average errors of 3.5 named storms, 2.3 hurricanes, and 1.4 intense hurricanes. Only NOAA's May ACE forecast was significantly better than climatology, averaging 58 ACE units off, compared to the 74 for climatology. Using another way to measure skill, the Mean Squared Error, May NOAA forecasts for named storms, hurricanes, and intense hurricanes had a skill of between 5% and 21% over a climatology forecast (Figure 2). Not surprisingly, NOAA's August forecasts were much better than the May forecasts, and did significantly better than a climatology forecast."

2) Lack of landfall projections.

If you think predicting the number of Atlantic hurricanes is hard, try predicting the number that will make landfall! There were no land falling hurricanes in the USA in 2009 or 2010. Even with an active season last year, an accurate seasonal hurricane forecast had no value in predicting hurricane damage potential.

Short term hurricane forecasts have more value:

The real, demonstrable value lies in short term hurricane forecasts such as those issued by the National Hurricane Center. A 2004 paper in The Journal of Applied Meteorology estimates the value of existing 48-hour hurricane forecast information to oil and gas producers averaged roughly $8 million per year during the 1990s, which substantially exceeds the operating budget of the National Hurricane Center.

It appears clear that the real return on investment value in improving hurricane forecasts lies in the continued improvement in short term hurricane landfall and intensity forecasts. The seasonal hurricane forecasts make great headlines, but are they really worth the time, effort and investment in research dollars?

Mosquito Tracker:

Those first pesky "Minnesota State Birds" are biting at the weather lab. If you live in the metro you can see where the MMCD has treated mosquito breeding areas near your home.

Good luck!

PH

June opens with AM sky show, active hurricane season?

Posted at 4:07 PM on May 31, 2011 by Paul Huttner
Filed under: Astronomy, Hurricanes

Can you believe it's June already?

June begins at midnight Wednesday, and signs of the season have arrived at the weather lab.

I saw and heard the first June Bugs sluggishly buzzing around the weather lab after dark Monday evening.

June is our brightest month in terms of daylight in Minnesota.

Daylight calculator shows 15.2 hours of daylight on June 1st for the Twin Cities.

You can calculate daylight for any location here.

Trademark long evening daylight peaks the last week of June, when sunset times are as late as 9:03pm in the metro, 9:14pm in the Brainerd Lakes area and 9:35 in Hallock in the northwest corner of Minnesota!

If you figure in "Civil Twilight" there is light in the sky as late as 10:17pm on clear evenings in the northwest corner of Minnesota in late June.

Sunrise sunset and "civil twilight" for Hallock, Minnesota in June.

You could call places like Roseau and Hallock land of the 10pm sun!

You can find sunrise & sunset times anywhere in Minnesota with this nifty sunrise & sunset calendar.

Morning Sky Show:

If you're an early riser there is still a nice grouping of planets in the sky before sunrise in the east.

Look to the east about 30-45 minutes before sunrise and you'll see Jupiter. Mars, Venus and Mercury shining brightly low on the eastern horizon.

Bright planets dot the pre-dawn horizon sky on June 1st.
(Image courtesy UA Flandrau Science Center)

The sky show is a remnant of the amazing show that lasted all month long in May. With so many cloudy mornings in May you might have missed out, but Wednesday morning looks clear in southern Minnesota at least.

Here's a description of the show as it unfolded in May from NASA.

Lightning strikes Willmar NOAA weather radio transmitter:

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
934 PM CDT MON MAY 30 2011

...PUBLIC INFORMATION STATEMENT...

THE WILMAR NOAA WEATHER RADIO TOWER IN NEW LONDON MN IS NOT
TRANSMITTING.

A LOCAL CITIZEN ALERTED THE NWS OF POSSIBLE PROBLEMS EARLIER THIS
EVENING. AFTER CONFIRMATION THAT INFORMATION WAS BEING SENT TO
THE RADIO...BUT WAS NOT DISTRIBUTED FROM THE TRANSMITTER...MN DOT
SENT A TECHNICIAN TO THE SITE TOO EVALUATE THE PROBLEM. THE
TECHNICIAN SUSPECTED THAT THE TOWER WAS STRUCK BY LIGHTNING AS
SEVERAL COMPONENTS HAVE MELTED. PARTS WILL BE ORDERED ON TUESDAY
BUT IT MAY TAKE SEVERAL DAYS FOR THE TRANSMITTER TO BE FIXED.

THOSE INDIVIDUALS THAT USE THE WILMAR TRANSMITTER AS THEIR PRIMARY
TRANSMITTER ARE ENCOURAGED TO TRY THE ST CLOUD TRANSMITTER...THE
OLIVIA TRANSMITTER OR THE KENSINGTON TRANSMITTER AS ALTERNATES TO
RECEIVE WEATHER AND WARNING INFORMATION. ANOTHER OPTION IS TO
REFER TO THE NWS TWIN CITIES WEB PAGE AT WWW.CRH.NOAA.GOV/MPX

Hurricane season opens June 1st!

After a winter packed with a parade of winter storms and the most tornadic spring since the 1950's you'd think the USA would be due for a break in extreme weather. Think again.

June 1st mark the "official" start of the Atlantic hurricane season. (June 1- November 30th)

Various forecast this year call for an above average number of tropical cyclones in the Atlantic Basin this year.

Hurricane expert Jeff Masters already sees potential tropical trouble brewing in the Caribbean Sea.

Total precipitable water (a measure of how much rain would fall if we condensed all the water vapor present) for May 31, 2011 at 7am EDT. Plentiful water vapor in the SW Caribbean would create about 2 inches of rain (50 mm, orange colors) if it were all condensed out. Image credit: University of Wisconsin CIMSS.

"The Atlantic hurricane season officially begins on Wednesday, June 1, but the Caribbean is already showing signs of the change of seasons. Moisture and heavy thunderstorm activity have increased in the region between Central America and Jamaica in recent days, and rainfall amounts of 1 - 2 inches have been common over the past three days over Cuba, Hispaniola, and much of Central America. The subtropical jet stream has been bringing high wind shear of 30 - 50 knots over the Caribbean the past week, but this shear has fallen to 20 - 40 knots this morning, and is predicted to fall below 20 knots by Thursday. All of the computer models predict that an area of low pressure will form in the region between Jamaica and Honduras by Thursday. This low will have the potential to develop into a tropical depression late this week. There is some dry air over the Western Caribbean near Mexico's Yucatan Peninsula that may retard the process, but a surge of moisture accompanying a tropical wave currently passing through the Lesser Antilles may counteract this, when the wave arrives in the Western Caribbean on Thursday. Water temperatures in the Central Caribbean are about 1°C above average, 29°C, which is plenty warm enough to support development of a tropical storm. Some recent runs of the NOGPAS model have predicted development of a tropical depression by late this week, potentially affecting Jamaica and Eastern Cuba. The other models have not been as gung-ho, but have been showing the potential for a strong tropical disturbance with very heavy rains forming late this week. In any case, residents of Jamaica, Cuba, the Cayman Islands, Haiti, Honduras, and Nicaragua should anticipate the possibility that heavy rains of 2 - 4 inches may affect them Thursday through Saturday this week."

The GFS model is hinting at a potential tropical system near Florida in about 10 days.

The USA got really lucky with no hurricane landfalls during an active Atlantic season in 2010. My hunch is that's not going to happen again this year, and we'll likely see some hurricanes and possible a major hurricane strike the U.S. Coastline this year.

Stay tuned!

PH

Wow Video: The 5 minute 2010 hurricane season

Posted at 6:00 AM on December 8, 2010 by Paul Huttner (3 Comments)
Filed under: Hurricanes

This is just too good.

If you have a minute (okay 5 minutes) fire up this mesmerizing NOAA time lapse video of the 2010 Atlantic Hurricane season. The 6 month hurricane season is condensed into 5 minutes. Run this full screen for the full effect.

A couple of key features jump out to my eye immediately and are worth looking for.

-Notice how as the storms form and move west in the tropical easterlies, then are suddenly steered away from the USA by the strong westerly winds over the eastern USA. We call this "recurvature." In 2010, the westerlies were relatively strong and quite persistent. Notice how they tear away at hurricane circulation as they encounter the shearing winds.

The strong westerlies combined with a frequent low pressure circulation just off the east coast over the North Atlantic; as they shoved one storm after another harmlessly away form U.S. soil in 2010.

-Also focus your eyes in the upper left part of the screen over Minnesota. You can see the fast moving jet stream dealing storm cluster after storm cluster over the Upper Midwest during the summer of 2010.

This pattern produced a record 104 (final) tornadoes in Minnesota in 2010, smashing the previous annual record of 74 from 2001, with Minnesota leading the nation in tornadoes for the first time ever on record in 2010.

It's pretty cool to watch half a year's weather wiz by in 5 minutes from 22,000 miles in space.

PH

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Storm Backwash: Windy, colder, snow showers

Posted at 7:39 AM on November 30, 2010 by Paul Huttner (1 Comments)
Filed under: Climate change, Hurricanes, Snow, Winter storms

Update 7:42 am:

Next batch of snow showers rotating into metro now. Expect wind, cold and snow showers to continue this morning, and gradually taper this afternoon.

Still accumulating snow in Duluth and northeast Minnesota today. Expect another 1" to 3" in much of northen Minnesota today. Duluth has picked up 5.5" so far...still snowing heavily at times.

MNDOT traffic cam at I-94 & Co Road 81 in NW metro shows snow slicked highway Tuesday morning.

Snowfall totals range from 1" to 2" around most of the metro...with 4" on the high end in Cambridge in the far north.

I've recorded 1" of snow at the Huttner Weather Lab in Deephaven. More impressively...I picked up .61" of rain Monday!

Redwood Falls gets the coveted (cursed?) Golden Snow Shovel Award with 10"!

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
555 AM CST TUE NOV 30 2010

...INITIAL SNOWFALL REPORTS SINCE MONDAY NIGHT...

THE TOTALS BELOW ARE SEPARATED INTO SNOW...AND ICE AND SLEET
CATEGORIES...THEN BY AMOUNT...AND ARE NOT NECESSARILY THE
FINAL AMOUNT FOR EACH LOCATION.

SNOW REPORTS LISTED BY AMOUNT

INCHES LOCATION ST COUNTY TIME
------- --------------------- -- -------------- -------
10.00 REDWOOD FALLS MN REDWOOD 0145 AM
5.00 BROOTEN MN STEARNS 0200 AM
4.50 COMFREY MN BROWN 0808 PM
4.30 MURDOCK MN SWIFT 0530 PM
4.00 CAMBRIDGE MN ISANTI 0545 AM
4.00 MAYNARD MN CHIPPEWA 0837 PM
4.00 8 W CLARA CITY MN CHIPPEWA 0837 PM
3.50 ALBANY MN STEARNS 0439 AM
3.50 OSAKIS MN DOUGLAS 0822 PM
2.50 WINTHROP MN SIBLEY 0622 PM
2.00 LITCHFIELD MN MEEKER 0150 AM
2.00 MORRIS MN STEVENS 0837 PM
2.00 MORGAN MN REDWOOD 0525 PM
1.70 LONG PRAIRIE MN TODD 0613 PM
1.50 GLENWOOD MN POPE 0808 PM
1.50 GAYLORD MN SIBLEY 0650 PM
1.00 MADISON MN LAC QUI PARLE 0837 PM

Also Waconia 1.8" & Prior Lake 1.2"...

A rather disorganized low pressure system is still winding up early Tuesday, even though most of the moisture fell as rain in eastern Minnesota and Wisconsin.

The next phase of this storm system will be wind, cold, and wrap around snow showers. Expect occasional waves of snow through Tuesday morning as the cold backwash on the back side of the system kicks in.

Rain changed to snow at the Huttner Weather Lab near the east end of Lake Minnetonka at 11:20pm.

Expect some slick roadways, especially west and north of the greater Twin Cities Tuesday for AM rush.

Some areas (including parts of the metro) will still see 1" to 3" total snowfall accumulations with occasional snow showery bursts today.

Winds will increase from the west and northwest Tuesday, gusting to over 30 mph in much of Minnesota. This will cause some blowing snow in open areas that have seen accumulations. Wet spots will freeze as temperatures drop Tuesday.

Temperatures will drop through the 20s, and wind chills will dip to near zero in many locations as winter like weather regains a foothold.

Wind chills will dip below zero by Tuesday evening.

Because of the storms westerly track and abundant moisture, the system was still able to crank out some impressive rainfall amounts in the warm sector. There were also some decent snow totals in the colder air on the storm's west side.

Here are some rain and snow totals as of late Monday evening.

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
914 PM CST MON NOV 29 2010

...INITIAL SNOWFALL REPORTS FROM MONDAY AFTERNOON AND EVENING...

THE TOTALS BELOW ARE SEPARATED INTO SNOW...AND ICE AND SLEET
CATEGORIES...THEN BY AMOUNT...AND ARE NOT NECESSARILY THE
FINAL AMOUNT FOR EACH LOCATION.

SNOW REPORTS LISTED BY AMOUNT

INCHES LOCATION ST COUNTY TIME
------ ----------------------- -- -------------- -------
4.50 COMFREY MN BROWN 0808 PM
4.30 MURDOCK MN SWIFT 0530 PM
4.00 MAYNARD MN CHIPPEWA 0837 PM
4.00 8 W CLARA CITY MN CHIPPEWA 0837 PM
3.50 OSAKIS MN DOUGLAS 0822 PM
2.50 WINTHROP MN SIBLEY 0622 PM
2.00 MORRIS MN STEVENS 0837 PM
2.00 REDWOOD FALLS MN REDWOOD 0645 PM
2.00 MORGAN MN REDWOOD 0525 PM
1.70 LONG PRAIRIE MN TODD 0613 PM
1.50 GLENWOOD MN POPE 0808 PM
1.50 GAYLORD MN SIBLEY 0650 PM
1.00 MADISON MN LAC QUI PARLE 0837 PM
0.50 HUTCHINSON MN MCLEOD 0653 PM

Some snow totals form Duluth NWS:

0838 PM DULUTH M1.7 INCH OFFICIAL NWS TOTAL SO FAR.

1004 PM 5 N VIRGINIA M5.0 INCH TRAINED SPOTTER

Allow some extra time getting around Tuesday.

Odds & ends:

-Winter starts off with a bang in Duluth.

This month Duluth recorded the most consecutive days with snowfall in nerly 17 years! Details here.

-USA "lucks out" in busy 2010 hurricane season.

One of the busiest on record with 19 named storms and 12 hurricanes. The USA escaped without a major land falling hurricane this year...remarkable considering the sheer number of storms. Favorable short term weather patterns steered one storm after another out to the open Atlantic.

An atmospheic "force field" seemed to steer storms away from the USA in 2010.

Details from NOAA here.

-Lakes getting warmer?

In the first comprehensive global survey of temperature trends in major lakes, NASA researchers determined Earth's largest lakes have warmed during the past 25 years in response to climate change.

Researchers Philipp Schneider and Simon Hook of NASA's Jet Propulsion Laboratory in Pasadena, Calif., used satellite data to measure the surface temperatures of 167 large lakes worldwide.

They reported an average warming rate of 0.45 degrees Celsius (0.81 degrees Fahrenheit) per decade, with some lakes warming as much as 1 degree Celsius (1.8 degrees Fahrenheit) per decade. The warming trend was global, and the greatest increases were in the mid- to high-latitudes of the Northern Hemisphere.

Lake Tahoe. (Credit NASA/JPL)

The story from NASA's JPL here.

PH

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Cold air lags: Lack of Canada snow cover

Posted at 8:42 AM on November 4, 2010 by Paul Huttner
Filed under: Hurricanes, Snow

It's November and finally a real Canadian air mass is surging south. But it's still above freezing and 10 degrees above average in most of Minnesota.

It seems Canadian cold fronts are just not what they used to be so far this fall.

A lack of snow cover over much of Canada so far this month may be the reason why our first November cold front features temperatures that are still at or above seasonal averages.

Air masses absorb and retain the properties of the regions they are born in and move over. Think of snow cover as a big block of ice...if you pass your hand over the top you can feel the cooler air. No snow, no cool air. Our air mass coming south from western Canada has travelled over bare ground on the trip to Minnesota.

If you travel northwest from Minnesota the ground is snow free for at least 1,000 miles.

A milder westerly air flow returns this weekend, and the lack of snow in the Upper Midwest will allow temperatures to recover more quickly than they might in other years. Hunters will enjoy mild conditions in the field this weekend, but will not have the benefit of "tracking snow."

East Coast swamped:

Low pressure east of Washington D.C. is dumping heavy rainfall to much of the eastern USA today. The space shuttle launch was scrubbed by bad weather today in Florida. Heavy rain is delaying flights in the northeast.

Tropical trouble for Haiti:

The Atlantic Hurricane season is not done just yet.

Tropical Storm Thomas may become Hurricane Thomas in the next 24 hours as it rakes Haiti through Friday. The storm will likely dump 5 to 10" (with isolated 15" totals) of unwelcome rainfall to the mountainous nation, which is still reeling from earthquake damage.

PH

Lucky hurricane season

Posted at 4:45 PM on October 14, 2010 by Paul Huttner
Filed under: Hurricanes

Predictions of an active Atlantic hurricane season have been in the ball park this year. The good news is the storms have steered clear of the USA.

Here are the numbers for Atlantic tropical cyclones so far in 2010:

16 named storms
9 hurricanes
5 major hurricanes

Those are some pretty respectable (and scary) numbers in a normal hurricane season. Amazingly, the USA has been spared a direct hurricane hit so far this year.

Take a look at the tracks below and you can see why. The primary steering mechanism for storms has been a large Bermuda high which curved storms around the west side of the ridge before they could reach the U.S. east coast. Other favored tracks this year have sent storms south into Mexico.

(Wikipedia Commons image courtesy Cyclonebiskit and Syntheticalconnections)

To have 5 major hurricanes in the Atlantic basin miss the USA is a lucky year.
Both the CSU (18 NS-10 Hurricanes-5 Major) and NOAA (17 NS-10 Hurricanes-5 Major) mid-season hurricane forecasts turned out pretty good this year for sheer numbers after a number of non-stellar forecast years.

Thankfully for the U.S. there has been a drought in major (Category 3 and higher) hurricanes striking the USA since 2005. The Pacific has also seen a relatively quiet season this year. More from hurricane expert Jeff Masters here.

PH

New GOES 15: Amazing Igor images

Posted at 8:20 AM on September 14, 2010 by Paul Huttner
Filed under: Hurricanes, Rainfall

NOAA is showing off some amazing images from the new GOES 15 weather satellite.

Check out the loop of Hurricane Igor. The loop begins with images every 30 minutes and then shows images every minute a few seconds in. Notice the incredible detail in Igor's eye. Talk about showing off a new weather toy!

GOES-15, has successfully completed five months of on-orbit testing and has been accepted into service. It is the third and final spacecraft in the GOES N-P Series of geostationary environmental weather satellites.

Wednesday super soaker:

Wednesday looks like a good day to test that new rain coat or umbrella. A strong low pressure system will slide east into Minnesota from the Dakotas Wednesday. Look for rain to begin in northwest Minnesota Wednesday morning, then spread east across the rest of the state by midday and afternoon. The heaviest, steadiest rains will fall from after lunchtime into early Wednesday evening before the rain tapers off Wednesday night from west to east.

(click for bigger image)

Rainfall totals could be significant. The models are cranking out between .50" and 1.50"+ depending on where you live, and the exact track of the system. Some isolated 2" amounts appear possible in a band north of the I-94 corridor from Alexandria to the north metro.

The sun will return on Thursday for a nice September day.

PH

Weather winning streak hits 3

Posted at 8:36 AM on September 13, 2010 by Paul Huttner (1 Comments)
Filed under: Hurricanes

Talk about perfect timing.

Minnesota's weather winning streak hit 3 today, as sunshine and comfortable temperatures rule for the 3rd consecutive day.

The best weekend weather in recent memory was welcome to those I spoke with this weekend. Total sunshine and highs near 70 Saturday and pushing 80 on Sunday in southern Minnesota was just the tonic for storm weary Minnesotans.

Highs reached 80 in southern Minnesota Sunday.

High pressure is in charge, and it will linger into part of Tuesday before the weather pattern begins to change. Look for more clouds Tuesday to mix in with some sun, and temperatures will run a few degrees cooler with mostly 60s statewide.

Next soaker Wednesday:

The next significant low pressure wave will ride into the forecast Wednesday. Look for rain to spread form west to east during the day. Some of the forecast models are wringing out .50"+ for southern Minnesota.

(click for bigger image)

The one day system gives way to sunshine again Thursday, before a strong cold front drops through Friday.

Weekend cool snap:

The coolest air so far this September appears headed this way for the upcoming weekend. Cool Canadian high pressure will nose into Minnesota, bringing likely frost to northern Minnesota and crisp nights in the 40s in the south. We should see plenty of sun next weekend, but highs may stall in the 50s north and lower 60s south.

Atlantic hurricane season in high gear:

Of all the hurricane names I's like to avoid, Igor tops the list. Hurricane Igor just sounds threatening and dangerous, and it is. With maximum sustained winds ripping at 150mph, Igor is a STRONG Category 4 hurricane Monday morning, and could reach rare Category 5 status today.

BULLETIN
HURRICANE IGOR ADVISORY NUMBER 21
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL112010
500 AM AST MON SEP 13 2010

...CATEGORY FOUR IGOR CONTINUES WESTWARD...

SUMMARY OF 500 AM AST...0900 UTC...INFORMATION
----------------------------------------------
LOCATION...17.7N 48.8W
ABOUT 940 MI...1515 KM E OF THE NORTHERN LEEWARD ISLANDS
MAXIMUM SUSTAINED WINDS...150 MPH...240 KM/HR
PRESENT MOVEMENT...W OR 270 DEGREES AT 13 MPH...20 KM/HR
MINIMUM CENTRAL PRESSURE...935 MB...27.61 INCHES

With Igor, Tropical Storm Julia off the Cape Verde Islands, and a gathering storm near Jamaica there are now three tropical systems sprawling out in the Atlantic.

The good news is it appears that none are a threat to the USA, at least for now.

PH

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Earl, Minnesota tornadoes, and a pretty good weekend.

Posted at 4:50 PM on September 2, 2010 by Paul Huttner
Filed under: Hurricanes, Tornadoes, Weekend

Talk about a close call.

As Hurricane Earl sideswipes the Outer Banks of North Carolina, the next potential target is battening down the hatches.

Cape Cod appears to be in line for another close encounter with Earl late Friday night.

Earl finally made the expected turn to the north-northeast late Thursday.

Though Earl is expected to weaken a bit ("weaker hurricane"...there's an oxymoron for you) it may still bring hurricane force winds to Cape Cod this weekend.

Gaston Next?

After Earl's east coast encounter all eyes will turn toward Gaston. Fiona is forecast to fizzle, but Gaston has at least some potential become a threat to the Gulf of Mexico and will bear watching next week.

Minnesota tornadoes generate international interest:

Not to overstate this, but I found it interesting to get a call today from a reporter in Canada about Minnesota's tornado numbers this year. Shane Judge is a reporter for the CBC News in Thunder Bay, Ontario. It seems our 145 preliminary tornado reports are getting some attention north of the border.

Shane says the meteorologists at Environment Canada (Canada's version of the National Weather Service) are reporting increased severe weather numbers this year in southwestern Ontario as well. You never think of Atikokan as tornado alley, but in this crazy summer it seems anything is possible.

Tanker runs aground in ice free Arctic:

It seems our new ice free summers in the Arctic are creating new opportunities and potential hazards for shipping. Check this out from CBC.

Pretty Good Weekend:

After Friday's foray into fall, the weather will mellow this weekend.

Look for a blustery Friday with highs on the 60s and a brisk gusty northwest wind at 15 to 30 mph over the lakes. Showers will spit rain in northeast Minnesota, and may roll down I-35 to just north and east of the metro by Friday PM.

Saturday and Sunday look spectacular statewide, and will be the best days to enjoy one last summer boat trip onto your favorite lake.

Look for plenty of sun, lighter winds and highs in the 60s Saturday with 70s statewide Sunday. Overnight lows will be nippy in the 40s north and near 50 south.

Labor Day will feature a strong southeast wind, a little more warmth and humidity and a chance of scattered thunderstorms.

PH

145 mph: Hurricane Earl near peak intensity

Posted at 8:30 AM on September 2, 2010 by Paul Huttner
Filed under: Hurricanes, Rainfall

The strongest storm of the Atlantic hurricane season so far is exploding with intensity today.

Hurricane Earl packs winds of 145 mph as it turns north for a brush with the Outer Banks of North Carolina tonight. Earl is at or near peak intensity today as it rides over the warm waters of the Gulf Stream.

Earl is a potentially catastrophic Category 4 hurricane on the Saffir-Simpson hurricane intensity scale.

Here are the Thursday AM stats on Earl from NHC:

BULLETIN
HURRICANE EARL INTERMEDIATE ADVISORY NUMBER 32A
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL072010
800 AM EDT THU SEP 02 2010

MAXIMUM SUSTAINED WINDS REMAIN NEAR 145 MPH...230 KM/HR...WITH
HIGHER GUSTS. EARL IS A CATEGORY FOUR HURRICANE ON THE
SAFFIR-SIMPSON HURRICANE WIND SCALE. A GRADUAL WEAKENING IS
EXPECTED TO START LATER TODAY...BUT EARL IS EXPECTED TO BE A MAJOR
HURRICANE WHEN IT PASSES NEAR THE OUTER BANKS.

The eye of Earl is expected to pass just east the Outer Banks late tonight. Hurricane force winds extend out 90 miles from Earl's center, and tropical storm force winds extend about 130 miles from Earl.

Regardless of the exact path of Earl's potentially devastating eyewall, the size of Earl will bring hurricane force winds and dangerous storm surge to the Outer Banks overnight tonight.

Cape Cod Next?

Earl's track has been shifted slightly to the west after about 24 hours. That brings the possibility of a direct hit or very near miss on Cape Cod into play Friday night into Saturday morning.

September chill blows in:

Get set for the coldest air mass in nearly 3 months.

Temperatures are in the 40s and upper 30s in Saskatchewan this morning. That chill air mass will spill in behind a cold front tonight.

Friday will bring blustery northwest winds and temperatures that will struggle to climb out of the 60s.

The Fairgrounds picked up .68" of rain this morning, making this likely the wettes day of the Fair in 2010. Look for a mix of clouds and sun today, with a few more pop up showers possible.

The weather will mellow for the Labor Day weekend with more sun and highs climbing back into the 70s. After a dry Saturday and Sunday, the next chance of showers will move this way on Labor Day.

PH

Earl takes aim

Posted at 5:28 PM on September 1, 2010 by Paul Huttner
Filed under: Hurricanes

They're battening down the hatches on the Outer Banks.

The NHC upgraded Hurricane Earl back to a Category 4 monster hurricane on the Saffir Simpson Hurricane Intensity Scale late Wednesday. Earl's track has also been shifting slightly west with each passing day, and the "official" track for Earl now brings the eye just off North Carolina's Outer Banks in the wee hours of Friday morning.

The wind field with Earl is large enough that hurricane force winds are now likely on the Outer Banks. Any westward shift of the track could bring Earl's potentially devastating eyewall ashore. Here's the discussion form NHC.

SATELLITE AND RECONNAISSANCE AIRCRAFT FIXES INDICATE THAT EARL
HAS BEEN MOVING RELENTLESSLY TOWARD THE NORTHWEST OR 310 DEGREES
AT 15 KNOTS. THE HURRICANE IS ABOUT TO REACH THE WESTERN EDGE OF
THE SUBTROPICAL RIDGE AND SHOULD BEGIN TO TURN MORE TO THE
NORTH-NORTHWEST AND NORTH LATER TONIGHT AND THURSDAY. IN ABOUT 36
HOURS OR SO...THE HURRICANE WILL ENCOUNTER THE BASE OF THE
MID-LATITUDE WESTERLIES AND SHOULD BEGIN TO RECURVE OR TURN TO THE
NORTHEAST WITH AN INCREASING FORWARD SPEED. THIS IS THE SOLUTION
CONSISTENTLY PROVIDED BY TRACK MODELS...WHICH HAVE EARL PASSING TO
THE EAST BUT NOT FAR FROM THE OUTER BANKS OF NORTH CAROLINA ON
THURSDAY NIGHT. ONLY A SMALL WESTWARD DEVIATION OF THE TRACK TO THE
WEST WOULD BRING THE CORE OF THE HURRICANE TO THE COAST.

GIVEN THE FORECAST TRACK...THE LARGE SIZE OF THE WIND FIELD...AND
THE EXPECTED INCREASE IN FORWARD SPEED WATCHES AND WARNINGS HAVE
BEEN EXTENDED NORTHWARD ALONG THE EAST COAST OF THE UNITED STATES.

Stay tuned as Earl takes aim at the Outer Banks and possibly the New England this week.

Colder fronts:

You'll notice a nip of September in the air by Friday.

An approaching cold front will kick off another bout of showers and T-Storms overnight into early Thursday. Behind the front, the season's coldest air pushes in.

Temperatures will not climb out of the 60s in most of Minnesota Friday.

Cold fronts gain strength as we move into September for one main reason. Shorter daylight and longer nights allow more radiational cooling at night. That means air masses coming out of Canada have had more time to cool off compared to June and July. We've lost over 2 hours and 15 minutes of daylight since June 21st in the metro. The longer nights mean progressively more potent cold fronts as we move deeper into September and October.

PH

Close Shave: Will Earl make U.S. landfall?

Posted at 5:17 PM on August 31, 2010 by Paul Huttner
Filed under: Hurricanes

Hurricane forecasters are sweating this one.

Major Hurricane Earl is making the turn toward the northwest, and headed directly for the Carolina Coast today. The "official" forecast is for Earl to turn north tomorrow and narrowly miss the Outer Banks of North Carolina. The track is so close that any jog to the west in the Earl's track could mean a direct hit on either the Outer Banks, or further up the East Coast toward Nantucket Island.

Earl has undergone an "eyewall replacement cycle" today. That means the eye has temporarily disappeared, but is likely to reform overnight. Earl could emerge as an even stronger storm when the latest eyewall replacement cycle is complete.

Hurricane Earl going through eyewall replacement. Note the dense line of clouds fanning out west of Earl. This is a low level "outflow boundary" generated by Earl. Loop courtesy University of Wisconsin CIMSS Satellite Blog.

Here are the latest stats on Earl from the NHC:

BULLETIN
HURRICANE EARL ADVISORY NUMBER 26...AMENDED
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL072010
500 PM AST TUE AUG 31 2010

INTERESTS FROM VIRGINIA NORTHWARD TO NEW ENGLAND SHOULD MONITOR
THE PROGRESS OF EARL.

Intensity forecasts keep Earl as a major hurricane for about the next 24 to 36 hours, with some gradual weakening after that as it approaches cooler waters.

Bottom line? The next 24 to 48 hours will be critical to watch for any changes in Earl's track, and to see how an upper level trough moving in from the west will recurve of Earl to the north.

As we say in the news and weather biz....stay tuned.

Temperature Shock Ahead: September chill Friday

You may be wondering what happened to summer by Friday. The strongest cold front of the season will plow through by Friday. After bouts of rain Thursday, temperatures may not climb out of the 60s Friday with a blustery northwest wind.

Friday could be the coolest day since June 13th when the metro reached 67 degrees!

It's going to feel like September out at the Fair Friday. The weather will mellow this weekend, and it looks like we'll warm back through the 70s to near 80 by Labor Day.

PH

Major Hurricane Earl: (And a slight severe risk for Minnesota)

Posted at 8:45 AM on August 31, 2010 by Paul Huttner
Filed under: Hurricanes, Rainfall, Severe weather

Powerful Hurricane Earl has the attention of the U.S. East Coast.

The powerful Category 4 storm is the season's first major hurricane, and it looks to make a close pass on North Carolina's Outer Banks Thursday. Here are the numbers from NHC.

BULLETIN
HURRICANE EARL INTERMEDIATE ADVISORY NUMBER 24B
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL072010
900 AM AST TUE AUG 31 2010

SUMMARY OF 900 AM AST...1300 UTC...INFORMATION
----------------------------------------------
LOCATION...21.0N 67.6W
ABOUT 200 MI...325 KM NNW OF SAN JUAN PUERTO RICO
ABOUT 230 MI...370 KM E OF GRAND TURK ISLAND
MAXIMUM SUSTAINED WINDS...135 MPH...215 KM/HR
PRESENT MOVEMENT...WNW OR 300 DEGREES AT 13 MPH...20 KM/HR
MINIMUM CENTRAL PRESSURE...935 MB...27.61 INCHES

Intensity forecasts for Earl fluctuate between about 135 and 140 mph for the next 36 hours, with a gradual decrease in wind speed after that. Earl will likely still be a major Category 3 or 4 hurricane as it brushes the North Carolina coast Thursday.

The latest model trends continue to push Earl westward, a little closer to the Carolina coast Thursday. There is a chance Earl could score a direct hit on the Outer Banks. Even if the center of Earl passes off shore, the storm will still trigger coastal flooding and erosion with pounding waves and storms surge.

Check out the radar loop from Pureto Rico as Earl passes by to the north of the island.

Storm risk again today:

Round one of thunderstorms woke many of us overnight. Lighting and heavy downpours we're the featured fare with the early AM storms.

NEXRAD storm total rainfall paints a swath of 2" to 3" rainfall west of the metro.

There are some impressive rainfall reports from overnight in southwest Minnesota.

Montevideo 2.20"
Granite Falls 3"

Amounts were lighter but significant in the Twin Cities area.

MSP Airport .35"
Huttner Weather Lab (west metro) .45"
Forest Lake .90"

Round #2 should develop this afternoon, but the intensity and location of the storms could be largely cloud dependant.

If the debris clouds from the morning storms breaks, and we get ample sun early this afternoon we could see storms fire near the metro late PM. If the clouds hold a little longer, storms may form east of the Twin Cities and shift the sever weather potential to Wisconsin, southeast Minnesota and Iowa.

Stay tuned for possible watches and warnings late this afternoon.

PH

Atlantic Roars: Tropical Storm in Iceland?

Posted at 5:15 PM on August 30, 2010 by Paul Huttner (1 Comments)
Filed under: Hurricanes, Severe weather

We don't really think of Iceland and Greenland as tropical storm territory, but that may change this week.

Tropical Storm Danielle is making her way through the North Atlantic these days. The still near hurricane strength storm is packing 70 mph winds about 425 miles SSE of Cape Race, Newfoundland.

The latest guidance for Danielle maintains tropical storm strength for the system as it moves north toward Iceland or the southern tip of Greenland in the next 5 days.

Tropical storms north of 55N are relatively rare, and Iceland sits at 65N. Pretty rare stuff in this summer of global weather extremes.

Earl intensifies:

Hurricane Earl has ramped up to a monster Category 4 hurricane. The fierce storm packs winds of 135mph as of late Monday.

Earl is expected to recurve just east of the eastern U.S. coastline and may graze the North Carolina Outer Banks and or Cape Cod with a glancing blow this week. High surf and coastal erosion will pound the beaches of the east coast this week. Look for you favorite Weather Channel reporter to be out in the pounding surf this week.

Fiona Forms:

The next tropical system is ramping up as an easterly wave that came off Cape Verde has become Tropical Storm Fiona. Hopefully "Fi" will not be as dangerous as our favorite Burn Notice character, but Fiona is expected to maintain strength as she tracks northwest toward the northern Lesser Antilles.

Expect storms to rumble across Minnesota from west to east overnight. Severe weather watches are posted tonight for the eastern Dakotas and northwest Minnesota.

Storms Return:

I'm back from vacation so that must mean that after a mostly storm free week, thunder is back in the forecast. If you're tired of the storms, I'm right there with you this summer.

Thunder may rumble into the Twin Cities metro well after midnight or toward morning, with the best chances for rain and thunder lingering through Tuesday. There will be a chance for some severe weather on Tuesday so keep a weather eye to the sky.

(click for bigger image)

PH

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Danielle has the spotlight

Posted at 2:23 PM on August 26, 2010 by Craig Edwards
Filed under: Hurricanes

Enhanced IR Satellite image of Danielle 215PM EDT.

Here is the late morning update on Danielle from the National Hurricane Center.

MAXIMUM SUSTAINED WINDS ARE NEAR 105 MPH...165 KM/HR...WITH HIGHER
GUSTS. DANIELLE IS A CATEGORY TWO HURRICANE ON THE SAFFIR-SIMPSON
HURRICANE WIND SCALE. SOME STRENGTHENING IS FORECAST DURING THE
NEXT 24-36 HOURS...AND DANIELLE COULD BECOME A MAJOR HURRICANE BY
TONIGHT OR FRIDAY.

HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 40 MILES...65 KM...FROM
THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 175 MILES...280 KM.

See the previous blog for the forecast track of Danielle. Tropical Storm Earl has the potential to increase to hurricane strength by Saturday.
CE

Dynamic duo

Posted at 7:21 AM on August 26, 2010 by Craig Edwards
Filed under: Hurricanes

National Hurricane Centers forecast track for Danielle.

As noted early in the week, we have entered the peak season for tropical weather. There are back to back storms that experts at the Hurricane Center are currently tracking. Danielle is expected to strenghten to major hurricane level in the next twenty-four hours as the center tracks northwest. Category three hurricanes, with sustained winds of greater than 110 miles an hour, are considered major hurricanes.

Tropical storm Earl is likely to strengthen into a hurricane by early Saturday. Follow the forecast track of Earl here.
CE

Open season in the Tropics

Posted at 7:02 AM on August 23, 2010 by Craig Edwards
Filed under: Hurricanes

From the Tropical Storm Prediction Center/NOAA, the historical tracking of the hurricane season. We have entered the peak season for hurricanes. Read on for more on the storm developing in the Atlantic.

Early Saturday morning conditions may have felt nearly tropical in southern Minnesota. Shortly after daybreak, shrouded by fog, the dewpoint matched the temperature of seventy degrees, resulting in one hundred percent humidity. If you were out jogging you finished with your shirt pasted to your body.

Today will be another warm one across the state, before a cool front blows through tonight. Look for a band of thundershowers to develop late afternoon in northwest Minnesota. The showers are likely to exit into Wisconsin before dawn on Tuesday.

You will notice the change in the air mass on Tuesday with refreshing northwest winds. The mercury will likely remain in the seventies in the warmth of the afternoon, falling into the 40s and 50s by early Wednesday morning. In the Twin Cities, expect Thursday morning to be the coolest morning since May 31st when we dipped to fifty-one degrees.

Meanwhile there is tropcial system that is likely to become Hurricane Danielle in the Atlantic. At this time there is no immediate threat to the US mainland. Track the forecast from the National Hurricane Center here.

Heat continues in the deep south, where the temperatures will exceed one hundred degrees in Texas today. Arlington will top out at about one hundred and three degrees late this afternoon.

Fresh air filters in

Posted at 8:30 AM on August 5, 2010 by Paul Huttner
Filed under: Aurora, Hurricanes, Northern lights

What a difference a day makes.

A dry and welcome transfusion of clean Canadian air is giving air conditioners a rest in the Upper Midwest today. Dew points have dropped from the tropical 70s into the comfortable 50s over the past 48 hours.

The drier air will last through Friday, before a warm front gurgles back north and brings a renewed surge of 90 degree heat and sticky humidity this weekend.

Dew points may spike well into the sticky 70s again by Sunday!
(click to enlarge image)

As the front bubbles north Saturday, it's likely a few thunderstorms will follow. One or two has the potential be severe later Saturday night into Sunday, according to SPC.

Aurora strikes again:

Reports indicate the northern lights flashed again last night in northern Europe. Apparently the sky was lit brightly enough to show the aurora over the city lights of Stockholm, Sweden. Amazing images were also captured over Norway.

Check out spaceweather.com to see the latest images.

Colin part 2?

The remnants of what once was tropical storm Colin show signs orf renewal in the Atlantic. NHC says there is a 50% chance that the system may reach tropical storm strength once again.

The suite of forecast models steer Colin harmlessly out to sea away from the east coast.

PH

Aurora Watch

Posted at 8:50 AM on August 3, 2010 by Paul Huttner
Filed under: Astronomy, Heat, Hurricanes

Late night star gazers may get a rare treat tonight.

A solar flare and significant coronal mass ejection (CME) is sending a burst of solar energy toward earth. The interaction with the earth's magnetosphere may produce auroras in the coming nights at high latitudes.

It is possible that auroras may be visible as far south as Minnesota. Keep an eye on the northern sky this week.

Welcome to the jungle.

Temperatures and humidity today will make it feel like the Amazon Jungle today in Minnesota. Temperatures will soar this afternoon to 90 degrees in much of southern Minnesota. Combine that reading with oppressive dew points in the 70s and you get heat indices (feels like) temperatures of 100.

Take it easy in the heat today; it can sneak up on you.

Steamy July:

Minnesota has been fortunate so far this summer. A nasty heat wave has been persistent in the central and southern USA with temperatures frequently topping 100.

Still, July made a mark in Minnesota. The average monthly temperature was 76.3 degrees. That's 3.1 degrees above average for the month, and a full 6.3 degrees warmer than last July!

July also marks the 5th straight month of above average temps in Minnesota.

Rainfall at Twin Cities Airport was 3.03" in July. That's an inch beow average. But just to show all weather (and especially rainfall) is local, Eau Claire got doused with 7.66" of rain last month. That marks the 4th wettest July on Record for Eau Claire.

Tropical Storm Colin:

We have the 3rd named storm of the Atlantic hurricane season. Tropical Storm Colin has 40 mph winds, and is still about 900 miles east of the Lesser Antilles.

Various forecast models take Colin to a point southeast of the Carolina Coast in about 5 days. It's too early to tell if Colin will become a threat to the eastern U.S.

PH

Weekend Outlook: Half decent

Posted at 4:40 PM on July 22, 2010 by Paul Huttner
Filed under: Hurricanes, Rainfall

It looks like a half decent weekend in Minnesota. The question is which half?

Here's the scoop. Plan the day at the lake for Sunday.

A slow moving low pressure system will bring another wave or two of rain and thunder through southern Minnesota and Iowa this weekend. The next wave overnight and into Friday morning should again favor areas along the I-90 corridor. A flash flood watch has been posted for southwest Minnesota into Friday.

1" to 3" rainfall totals last night has saturated ground in the southern quarter of Minnesota, and it won't take much additional rainfall to get rapid rises in rivers and creeks.

The highest risk for severe weather Friday appreas to be south of the metro in southern Minnesota and into Iowa and Wisconsin.

For the metro and points north, it appears the heaviest and more persistent rains may stay south of us until Friday night. In fact, some of the models portray a fairly nice weather pattern until the next wave of storms rumbles in Friday night. That's the wave that could linger into Saturday, keeping a few persistent showers in the forecast until things finally clear out late in the day Saturday.

Sunday still looks like a classic. Plenty of sun, low humidity and warm temps in the 80s.

Tracking Bonnie?

Indications are Tropical Storm Bonnie may graze the southern tip of Florida and move into the Gulf of Mexico this weekend.

PH

NHC: 60% chance for Tropical Storm Bonnie

Posted at 5:08 PM on July 20, 2010 by Paul Huttner
Filed under: Hurricanes

We may be saying hello to Tropical Storm Bonnie in the next 48 hours.

The National Hurricane Center is giving a vigorous tropical wave near Puerto Rico a 60% chance of strengthening into a tropical storm in the next 48 hours.

Tropical wave near Puerto Rico shows signs of development

If the system develops, it would become the second named storms of the season, Bonnie.

Bonnie is fighting a few variables in terms of development, according to Dr. Jeff Masters, hurricane guru at Weather Underground. Dry air out ahead of Bonnie may retard development.

Also in favor of development are the warm ocean temperatures of 29°C. The SHIPS model predicts shear will stay in the moderate range, 10 - 20 knots, over the next five days. The primary detriment to development of 97L over the next three days will probably be the presence of dry, stable air in its path over the Bahamas, thanks to the upper-level low to the north of the Dominican Republic. If the center forms close to the coast of the Dominican Republic, the high mountains of Hispaniola may also be a problem for the storm. NHC is giving 97L a 60% chance of developing into a tropical depression by Thursday, which is a reasonable forecast. I think there is a 70% chance 97L will eventually become Tropical Storm Bonnie, sometime in the next five days. Sudden rapid development today or on Wednesday is unlikely, due to the dry air over the Bahamas. I put the odds of 97L making it to hurricane strength before reaching Florida at 30%, and I give a 20% chance it will be a hurricane in the Gulf of Mexico. The probability of 97L being a hurricane in the Gulf of Mexico will depend heavily upon how long the storm spends over land or interacting with land over the next four days, which is very uncertain.

Various forecast models are pushing what could become Bonnie toward south Florida by Thursday or Friday. The system may possible track into the eastern Gulf of Mexico after that.

All eyes in the southeast U.S. will be watching for the potential for Bonnie in the coming days.

PH

Massive Mayfly hatch detected on doppler radar

Posted at 8:25 AM on July 20, 2010 by Paul Huttner (2 Comments)
Filed under: Climate change, Hurricanes, Remote sensing

The folks who invented Doppler never expected this.

A massive Mayfly hatch over the Mississippi last night near La Crosse shows up brilliantly on the Doppler radar reflectivity loop last night. The hatch occurred between about 9pm and 10pm from near Winona south through La Crosse and to near Guttenberg, Iowa.

Mayfly "cloud" visible on NWS La Crosse doppler radar Monday night.

As the dense "cloud" of Mayflies hatches and drifts over the river valley, it shows up on Doppler as the radar beam hits the cloud and returns to the radar site. Doppler radar is so sensitive that birds, insects and even dust are visible in clear air mode.

Tropical Storm Bonnie?

The National Hurricane Center has upgraded the chance that a tropical wave near Puerto Rico will strengthen into a tropical storm within the next 48 hours from 20% to 40%. If it does, it would become tropical storm Bonnie.

Many forecast models then track the system toward the southeastern United States.

Stay tuned.

2010: Hottest year on record so far

It's either the mother of all coincidences or climate change is kicking into high gear.

We're half way through 2010 and NOAA reports that globally this is the hottest year on record so far. Check out these startling facts.

-June 2010 was the hottest on record globally (+1.22 degrees F)
-The past 4 MONTHS (Mar-Jun) have all been the hottest on record globally!
-2010 is on pace to be the hottest year on record globally (+1.22 degrees F)
-June was the 304th consecutive month above average globally!
-The last below average month was 25 years ago, February 1985. That's a lifetime for nearly 1/3 of the world's population.

2010 is on pace to surpass 1998 as the hottest year on record globally.

The data takes the wind out of the sails of those who would claim that the earth has been "cooling" since 1998. The 10 hottest years globally have all occurred since 1998, and there has not been one cooler than average year globally in 25 years.

You do the math.

PH

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Forecast: Rain chances increase

Posted at 8:25 AM on July 7, 2010 by Paul Huttner (3 Comments)
Filed under: Heat, Hurricanes, Rainfall

It may feel like the Amazon jungle around here one more time today.

Pooling surface moisture and an approaching cool front may trigger scattered showers and tropical downpours again this afternoon and evening in the southeast half of Minnesota.

(click for bigger image)

If the storms get going, some of the rainfall could be locally heavy.

NAM 84 hour rainfall shows 1" to 2" rainfall "bull's eye" right over Twin Cities metro.

Rainfall may exceed 1" in some areas. (click for bigger image)

Tropical dew point levels in the upper 60s and low 70s have been pooling down in Iowa. That moisture may get drawn north ahead of the front later today. Keep an eye out for developing showers and T-Storms anytime after 3pm and into tonight.

As the cool front sweeps through Thursday, a much drier air mass will bring an end to shower chances for a few days and usher in a much more comfortable less humid air mass. You can probably give the air conditioner a rest after today.

Forecast models indicate dew points falling into the comfortable 50s later this week.

Brewing Bonnie?

Watchful eyes are on a developing tropical wave moving into the southern Gulf of Mexico today. NHC says there is a 40% chance that the wave may become Tropical Storm Bonnie before landfall near the Texas Mexico border Thursday.

East Coast Heat Wave Day 2:

Many locations along the eastern seaboard will hit 100 again today. All six observing sites in the New York City area broke records Tuesday with Central Park sweltering at 103 degrees.

We can be grateful for some of the best (and most comfortable) weather on the planet the next few days.

PH

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Tropical Trouble

Posted at 8:40 AM on July 6, 2010 by Paul Huttner
Filed under: Hurricanes, Rainfall

A tropical wave near Mexico's Yucatan Peninsula may strengthen as it moves into the Gulf of Mexico over the next 48 hours.

Weather eyes are on the Gulf of Mexico this week as one tropical wave pounds Louisiana with choppy seas and heavy downpours. Meanwhile, a second and stronger tropical wave is brewing near the Yucatan which could move into the Gulf and strengthen over the next 48 hours. NHC is giving the disturbance about a 30% chance of developing into the Atlantic's second named storm of the season.

Indications are the upper level steering currents will continue to move the wave northwest. Various forecast models are taking he system toward the Texas coast later this week. Overall conditions appear favorable for development, and all eyes will be on the Texas coast later this week.

Eastern Heat Wave:

It's way hotter than the 4th of July out east. Highs will reach 100 degrees today from New York to D.C. as a big area of intense high pressure sprawls out.

The so called Bermuda or Azores High often shifts west and sets up shop over the eastern U.S. during the summer months. This week, the system will trap heat over the east coast. Record power demand is forecast in many eastern cities as residents try to stay cool during the heat wave.

Minnesota's Rain Forest:

If you feel like you're living in the Amazon Jungle this week, you're not far off. Dew points with our extremely humid air mass have been in the 70s. That's a tropical moisture level we only see a few times during the summer in Minnesota.

With that kind of moisture in the air, tropical downpours can dump heavy rain in just a few minutes. Rainfall totals last night ranged from 1" to over 3" in and around eastern Minnesota and the Twin Cities.

The sweaty air mass will linger through Wednesday, before a drier Canadian air mass eases in Thursday and Friday, bringing relief to sweaty Minnesotans.

PH

Alex eyes landfall

Posted at 8:25 AM on June 30, 2010 by Paul Huttner
Filed under: Hurricanes

It didn't take long this year to produce the Atlantic's 1st hurricane.

GOES visible image shows a better organized Hurricane Alex approaching Mexico's Gulf Coast Wednesday.

Hurricane Alex is moving slowly (WNW 7 mph) toward shore today and is expected to make landfall along the coast of Mexico south of the Texas border just after midnight Thursday.

Here are the stats as of early Wednesday from NHC. Updated stats here.

BULLETIN
HURRICANE ALEX INTERMEDIATE ADVISORY NUMBER 19A
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010
700 AM CDT WED JUN 30 2010

SUMMARY OF 700 AM CDT...1200 UTC...INFORMATION
----------------------------------------------
LOCATION...23.4N 95.3W
ABOUT 155 MI...250 KM E OF LA PESCA MEXICO
ABOUT 220 MI...355 KM SE OF BROWNSVILLE TEXAS
MAXIMUM SUSTAINED WINDS...80 MPH...130 KM/HR
PRESENT MOVEMENT...WNW OR 290 DEGREES AT 7 MPH...11 KM/HR
MINIMUM CENTRAL PRESSURE...959 MB...28.32 INCHES

Alex is a Category 1 storm on the Saffir-Simpson scale, but the slow moving storm may have enough time over the warm Gulf waters to strengthen before moving ashore. Winds could approach 100 mph just before landfall.

Alex is the first June hurricane to form in the Atlantic since 1995.

Rain bands from Alex reach as far east as the Louisiana coast today. Since Alex is a slow mover, one of the biggest threats will be extremely heavy rainfall in the order of 6 to 12 inches with isolated 20 inch totals over the next two days in northern Mexico and south Texas.

PH

Alex may become season's 1st hurricane

Posted at 3:33 PM on June 28, 2010 by Paul Huttner (1 Comments)
Filed under: Hurricanes

A somewhat disorganized Tropical Storm Alex may become the 1st hurricane of the Atlantic season in the next 48 hours.

Alex is located in the Bay of Campeche about 85 miles west of Campeche, Mexico. The storm has passed over land, and the interaction with the Yucatan Peninsula has prevented further strengthening so far. Conditions appear more favorable over the next 36 hours fro Alex to become the Atlantic's first hurricane of the 2010 season.

Here are the stats from NHC:

SUMMARY OF 100 PM CDT...1800 UTC...INFORMATION
----------------------------------------------
LOCATION...20.3N 91.7W
ABOUT 85 MI...135 KM WNW OF CAMPECHE MEXICO
ABOUT 535 MI...860 KM SE OF BROWNSVILLE TEXAS
MAXIMUM SUSTAINED WINDS...60 MPH...95 KM/HR
PRESENT MOVEMENT...NNW OR 330 DEGREES AT 5 MPH...7 KM/HR
MINIMUM CENTRAL PRESSURE...990 MB...29.23 INCHES

NHC track for Alex

The official NHC track forecast takes Alex ashore just south of the Texas-Mexico border Thursday morning as a Category 2 hurricane on the Saffir-Simpson hurricane intensity scale with winds near 98 mph.

There has been some northward shift in the forecast track in the past few runs, but for now it still appears the brunt of the storm should pass south of the BP Horizon spill zone.

Still a storm that big will generate some increased ocean swells and wave heights along the Gulf Coast, which could be problematic for cleanup and containment efforts later this week.

PH

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Will hurricanes spread Gulf oil inland?

Posted at 8:50 AM on May 17, 2010 by Paul Huttner
Filed under: Gulf oil spill, Hurricanes

With the 2010 hurricane season just around the corner (June1-Nov 30th) there has been considerable speculation as to what will happen if/when a hurricane strikes the oil slick area in the Gulf of Mexico.

NASA MODIS satellite image shows growing oil slick off the Mississippi Delta on May 11th.
(click for bigger image)

This year there may be increased reason for concern. Hurricane forecasters expect an above average number of Atlantic hurricanes this year. And already tropical Atlantic SST's are running as much as 2 degrees C above average in the main development area (MDA) for Atlantic Hurricanes off the African coast.

The record warm water temperatures support the notion of increased Atlantic hurricane activity this year.

Tropcal Atlantic SST anomalies shows record warm water in the eastern Atlantic.

Here's what meteorologists know and don't know about hurricanes interacting with the Gulf of Mexico oil spill.

What we think we know:

Hurricane development & intensity

-According to Dennis Feltgen from the National Hurricane Center, the oil slick wouldn't affect a hurricane's intensity or track. The circulations are too big and too well established, and hurricanes are driven by steering currents far above the ocean's surface.

-Oil on the ocean's surface DOES suppress evaporation of sea water. That could act to suppress tropical storm development as evaporation is a primary driver of tropical cyclone development.

Oil spill containment:

-High winds and rough seas would likely stop containment efforts destroy containment booms, opening shores to oil.

-Storm surges would likely carry increased volumes of oil to inland bays and beaches.

What we don't know:

-There is the possibility that hurricane force winds could lift oil off the sea surface and send it airborne in a blowing oily sea spray. If the oil and dispersant is aerosolized, it could be carried far inland and become a threat to crops and human health. We don't know what kind of wind speeds it would take to do this, and how far the toxic oily spray could travel. This is likely a worst case scenario.

-Will the Gulf Loop Current tap into the oil slick and drive it around Florida and toward the east coast? This may increase the likelihood of a hurricane impact over an oil slicked area.

Gulf of Mexico "Loop Current" may push oil eastward over time.

Bottom line: A hurricane over a major oil spill has never happened before in human history. We are literally in uncharted waters here. This is like a big lab experiment that may take place over the next 6 months. We just don't know how an oil slick this size and hurricanes will interact.

We may find out in the coming months.

PH

CSU Hurricane Forecasts: Where's the value?

Posted at 5:01 PM on April 7, 2010 by Paul Huttner
Filed under: Hurricanes

The annual April seasonal hurricane forecast is out today from the folks at Colorado State University (CSU) led by Phil Klotzbach and Dr. William Gray. After the past few years of iffy forecast results, some are asking; where's the value in producing seasonal hurricane forecasts?

The 2009 forecast was a huge bust for the CSU team. On April 7, 2009, the CSU team issued the spring updated forecast for the 2009 season. They called for near-average activity in 2009 of 12 named storms and 6 hurricanes.

Instead, 2009 produced just 9 named Atlantic storms and only 3 hurricanes. That's the fewest number of Atlantic hurricanes since 1997. No hurricanes made landfall in the United States in 2009.

Tracks of named storms in the 2009 Atlantic hurricane season.

Looking back at the past 5 years of April CSU hurricane forecasts, the accuracy of the CSU seasonal hurricane forecasts is at best mixed. They had a very good year in 2008, but in every other year the forecasts have show an error rate of 33% or higher in either the number of named storms or hurricanes. In addition to badly missing the lowest number of hurricanes since 1997 in the 2009 forecast, CSU's April 2005 forecast of 13 named storms and 7 hurricanes completely missed the notion of the most active Atlantic hurricane season on record. In addition to the devastating Hurricanes Katrina and Rita, 2005 produced a record 28 named storms and 15 hurricanes in the Atlantic. The CSU team under forecast both the number of named storms and hurricanes in 2005 by over 50%.

There are several groups in addition to the renowned CSU forecasters that issue seasonal hurricane forecasts. NOAA, and private forecasters such as Britian's Tropical Storm Risk also produce seasonal hurricane forecasts. Many in the insurance industry are now questioning the accuracy and usefulness of seasonal hurricane forecasts.

A recent post from The National Association of Professional Insurance Agents asks the following question:

"What's the Insurance Value of Pre-season Hurricane Predictions?"

February 2, 2010

The bottom line for those living in hurricane country is that you have to prepare for each hurricane season in the same way. The great variability in the number and intensity of storms from one year to the next does not seem to allow us to extract great value from seasonal hurricane forecasts.

Short term hurricane forecasts have more value:

The real, demonstrable value lies in short term hurricane forecasts such as those issued by the National Hurricane Center. A 2004 paper in The Journal of Applied Meteorology estimates the value of existing 48-hour hurricane forecast information to oil and gas producers averaged roughly $8 million per year during the 1990s, which substantially exceeds the operating budget of the National Hurricane Center.

It appears clear that the real return on investment value in improving hurricane forecasts lies in the continued improvement in short term hurricane landfall and intensity forecasts. The seasonal hurricane forecasts make great headlines, but are they really worth the time, effort and investment in research dollars?

PH