Updraft: November 16, 2011 Archive

Cold now; Snow trends north Saturday; 50 by Thanksgiving?

Posted at 9:02 AM on November 16, 2011 by Paul Huttner (1 Comments)
Filed under: Cold, Severe weather, Winter 2011-12, Winter storms

Updraft Headlines:

Today's World Sunlight Map shows daybreak in Minnesota.
(Click images to enlarge)

25 degrees in the metro this morning!

March 30th - last time it was this cold in Minnesota (Nearly 8 months ago)

19 degrees - forecast low in the metro Thursday morning!

70% chance - Weather Lab estimate for a "plowable" snow in Brainerd, Duluth & Iron Range by Saturday night

30% chance - Weather Lab estimate for season's first 1" snowfall at MSP Airport Saturday night

71% of peope first heard about storms in Tuscaloosa tornado outbreak on TV & radio

5% first heard of storm though "social media"

Novembrrrrrr!

It's finally here.

The coldest air mass in nearly 8 months has invaded Minnesota. This one feels different. Last night's bracing, window rattling northwest wind made you hunch over and step lively to get into the car.

The temps plunged to 25 this morning at MSP, with a few teens up north. Wind chills made it feel like teens and single digits in Minnesota this morning.

Yes, it's back!

Our wintery preview peaks tonight and early Thursday, as temps bottom out in the teens south with a few single digits north.

Temps will begin to moderate Thursday and should reach the 40s again (with a shot at 50 in the south) by Friday afternoon.

Saturday Snow: Trending north

The forecast models are fairly consistent with the track of our potential weekend winter storm. The latest runs seem to favor a surface low track near La Crosse by Saturday night.

If the GFS is right, the rain snow line looks to be setting up from near Redwood Falls to St. Cloud most of Saturday.

The temperatures profile for the storm appears to be warm enough for motly rain in the metro, changing to a little burst of wet snow as the storm slides by later Saturday night.

Moisture fields also show a rapid drop off in precip totals along the southern edge of the storm, with system precipitation totals as low as .25" in the metro.

The track, temp and moisture fields still suggest the heaviest "plowable" snow band setting up along an Alexandria-Brainerd-Iron Range-North Shore line. These areas could be in line for potentially 6" or more by early Sunday morning.

GFS snowfall map shows Saturday snow potential.

Tracks can still change...stay tuned on this one!

Mild Thanksgiving Day?

The early look at Thanksgiving trends mild. Assuming bare ground and some sun (which seems likely at this point) southerly winds should help boost temps to near 50 again in southern Minnesota.

"Old Media" still rules in severe weather outbreaks

Many people these days get a forecast or radar snapshot from their smart phone.

But in last year's devastating tornado outbreaks in Tuscaloosa and other markets, TV and radio were still king.

Research from Raycom Media (yes, a TV company) shows that as many as 71% of all people first heard about the coming storms from TV, with radio the second choice.

Only 5% of people first heard about the storms through Internet or mobile devices. Of those who did sample the Internet, 50% went to TV or radio websites for information.

"Chances are you know someone who has been affected by the floods, fires, tornadoes, earthquakes or hurricanes this past year. You may have even been impacted yourself. In Alabama, on April 27, a series of tornadoes destroyed more than 13,000 homes and killed 246 people in a matter of a few hours. The storms hit very close to home -- physically and emotionally -- with our Montgomery, Birmingham and Huntsville stations directly affected.

It was impressive to see the stations spring into action with life-saving information for our communities as the storms approached and then with wall-to-wall coverage of the aftermath.

In an effort to fully understand our viewer's needs in the wake of the storms, the senior management at Raycom Media commissioned me to do a survey in our three affected DMAs as well as Tuscaloosa, the area with the most damage.

We learned that 71% of adults living in these affected areas first learned about the approaching storms through TV. Schools and businesses were closed early in an effort to get people off the roads and 75% of residents were at home when the storms hit. Seventy-nine percent were tracking the storms on TV as they impacted their communities.

It is probably not surprising that viewers relied on their local stations more than any other medium for information on the storms. This was true for every age group, including 18-24 year-olds, and was particularly true in African-American households, which relied on television at a higher rate than the population in general.

We received many comments putting emotion behind these numbers. Many said that next time, they would "stay tuned to the weather reports" and "keep a close eye on the news" in order to stay safe. Some went so far to say they would "make sure I have a battery-powered TV." I conducted a focus group recently and when the conversation turned to one local meteorologist, one of the participants said: "He saved my life." No other endorsement is needed.

Power was an issue, especially in Huntsville. Many in that area reported they could not watch TV because of power outages. So they turned to radio, which ranked as the second-highest medium during the crisis. Because TV stations have partnered with radio stations during breaking weather and news events, radio listeners were actually able to get the same information as TV viewers were.

Although only a few (5%) of respondents reported going to the Internet for information tracking the storms, half of those were going to a station websites. Additionally, 5% were receiving information on mobile sites. Stations were active in distributing information via their own broadcasts, on the radio, on the Internet and even on mobile to keep their communities safe."

It seems people may still depend on the "live and local" severe weather information they get from local media most during severe weather outbreaks.

PH

(1 Comments)

Zig-Zag: Saturday snow threat shifts south toward Metro!

Posted at 4:47 PM on November 16, 2011 by Paul Huttner
Filed under: Winter 2011-12, Winter storms

Updraft Headlines:

13 degrees - dew point in the Twin Cities Wednesday

45 degrees - dew point in Phoenix, AZ Wednesday in the Sonoran Desert
(More than twice the moisture in Phoenix vs. the Twin Cities)

60 - 90 miles - southward shift on storm track for Saturday's potential snow event

50% chance - Latest Weather Lab estimate for a plowable snow in Brainerd & Duluth Saturday

60% chance - Latest Weather Lab estimate for the first 1" snowfall at MSP Airport Saturday night

***

Growing metro snow chances Saturday?

This is why responsible meteorologists don't make specific snowfall predictions 3 days to a week in advance of a potential snowfall. It's also why we usually turn prematurely gray!

In the latest forecast model twist, the GFS and NAM models have locked on to a "southern solution" for our potential Saturday snow event. That shift would put the center of accumulating snow close to or right over the Twin Cities metro.

Here's the latest thinking from the weather lab on our growing snowfall chances this weekend.

The System:

The same "Colorado Low" I've been tracking all week. Low pressure spins up in Colorado Friday, and quickly races northeast on a fast moving jet stream toward the Upper Midwest Saturday.

Storm Track:

The latest model runs shift the storm track 60 to 90 miles south. If it verifies, that would bring the rain snow line south of the metro, meaning accumulating snow for the highly populated Twin Cities.

The latest model tracks bring the surface low through Iowa to south of La Crosse by late Saturday.

GFS model 6pm Saturday shows surface low in NE Iowa. Rain snow line (white) is south of the metro with snow in metro.

This is a far more favorable track for accumulating snow in St. Cloud and the Twin Cities.

Timing:

Rain and snow should develop Saturday and linger into Saturday night.

Temperature Profile:

The southward track shift brings the critical rain-snow line south to a Mankato-Twin Cities line around midday Saturday. As the system swings by, any rain or mixed precip would quickly change to snow Saturday afternoon in the metro.

Potential Accumulations?

With 48 to 60 hours until the core of event, It's still too early to pinpoint or issue credible specific snowfall forecasts.

The models have already shifted the track of Saturday's system a few times, and may do it yet again over the next 48 hours.

I could tell you there is going to be 6" of snow in Brainerd or Duluth, but it's just not credible to say that reliably yet. In fact the latest model runs are leaning lower than that total.

The best thinking/advice at this point is to say there is a growing chance of accumulating snow Saturday and Saturday night for the metro and south central Minnesota cities like Willmar, Mankato and St. Cloud. You may want to locate your shovel just in case!

GFS 120 hr snowfall shifts accumulating snow into metro!

One key observation of this system so far is that the models are consistent in keeping it as an "open wave." This means the system would move through faster than a "closed low" keeping potential snowfall totals down.

The Weather Lab philosophy is to issue specific snowfall forecasts about 24 hours in advance of anticipated snowfall. This is generally the peak window between letting the models reach peak accuracy, and giving listeners enough time to react accordingly.

Even with great advances in forecast models, forecasting snowfall is among the most difficult forecasts a meteorologist has to make. It's just not credible to throw out specific totals days or a week in advance. I wish it was different, but the state of the science of meteorology just isn't good enough to make consistently accurate snowfall forecasts days in advance. Anyone who tells you otherwise is blowing smoke.

Stay tuned as new model runs come in through Thursday & Friday. This system will probably throw a few new twists at us yet!

NOAA "Greehouse Gas Index" on the rise in 2010:

Measurements by NOAA confirm what we already know. We're putting more greenhouse gasses into our atmosphere every year.

According to the index, earth's greenhouse gasses have become 29% more efficient at warming the planet since 1990.

One interesting twist is that while CO2 continues a steady rise, atmospheric methane is rising after a decade of holding steady. Some climate scientists fear that Arctic warming is releasing more methane into the atmosphere. Methane is a very efficient greenhouse gas.

From NOAA:

•A continued steady increase in carbon dioxide: Global carbon dioxide levels rose to an average of 389 parts per million in 2010, compared with 386 ppm in 2009, and 354 in the index or comparison year of 1990. Before the Industrial Revolution of the 1880s, carbon dioxide concentration in the atmosphere was about 280 ppm. Carbon dioxide levels swing up and down in natural seasonal cycles, but human activities - primarily the burning of coal, oil, and gas for transportation and power - have driven a consistent upward trend in concentration.

•A continued recent increase in methane: Methane levels rose in 2010 for the fourth consecutive year after remaining nearly constant for the preceding 10 years, up to 1799 parts per billion. Methane measured 1794 ppb in 2009, and 1714 ppb in 1990. Pound for pound, methane is 25 times more potent as a greenhouse gas than carbon dioxide, but there's less of it in the atmosphere.

PH