Updraft: April 19, 2012 Archive

Tornado drill today; Sirens 1:45 & 6:55pm; Rain today, 80 next week?

Posted at 9:00 AM on April 19, 2012 by Paul Huttner (2 Comments)

Statewide tornado drill today

1:45pm & 6:55pm sirens will sound in most counties

Rain today (but not severe) in southern Minnesota

Wet snowflakes possible tonight as system winds down

2nd rain shot Saturday - wet snow in Duluth?

Sunday - sunnier & nicer day this weekend

80 by Wednesday? Warming trend next week

Severe? - models hint at possible severe in Minnesota by Thursday & Friday next week

Source: NOAA

Statewide tornado drill today:

Yes those are sirens you'll hear today!

The NWS is conducting the annual statewide tornado drill today in Minnesota and western Wisconsin. In most counties, the sirens will blow at 1:45pm & 6:55pm.

Here are the details from the Twin Cities NWS:

Tornado Watch/Warning Drills

The National Weather Service, Wisconsin Emergency Management, the Minnesota Division of Homeland Security and Emergency Management, and other state, county and local agencies have come together to host Severe Weather Awareness Week activities. On Thursday, April 19th, simulated tornado watches and warnings will be issued to test the statewide warning and communications systems. The schedule for April 19th is as follows:

(all times CDT)

1:00 PM: The National Weather Service will issue a simulated tornado watch for Minnesota and Wisconsin.

1:45 PM: The National Weather Service will issue a simulated tornado warning for 9 counties of western Wisconsin (Barron, Chippewa, Dunn, Eau Claire, Pepin, Pierce, Polk, Rusk and St Croix). Note that most cities and counties will activate outdoor warning siren systems.

1:45 PM: The National Weather Service will issue a simulated tornado warning for Minnesota counties. Note that most cities and counties will activate outdoor warning siren systems.

2:00 PM: The National Weather Service will issue an "End of Test" message using the Severe Weather Statement product. It should be stated that outdoor warning sirens will not be sounded again for this all clear, nor will there be any warning tone on NOAA Weather Radio.

6:55 PM: Another simulated tornado warning will be issued for 81 participating counties in Minnesota. Those counties not participating are: Aitkin, Becker, Houston, Kittson, Norman, and Wilkin.

All about sirens:

Sirens can be some of the most effective, and most misunderstood warning tools in severe weather. Here are some facts, and some of my random thoughts about sirens.

NWS siren facts below:

Siren Activation Information Counties and cities own the sirens, and therefore decide how and when to activate them. The National Weather Service does not sound them.

There are many different policies regarding siren activation that are used by the various cities and counties. Some will activate sirens across the entire county for tornado warnings only. Others will activate sirens countywide for tornado warnings and all severe thunderstorm warnings. Some will activate sirens across the entire county for tornado warnings and severe thunderstorms that have winds of at least 70 or 75 mph. Others will activate sirens only for portions of counties. Local officials may also sound the sirens anytime they believe severe weather is a threat, even if there is no warning from the National Weather Service.

Sirens normall sound for about three minutes, and then go silent. It is very rare to keep the sirens sounding for the entire warning, since that would cause the backup battery to run out, which would be critical in the event that power goes out. Furthermore, the siren motor will fail much more quickly if the siren sounds continuously. Some jurisdictions may repeat siren activation every few minutes.

There is no such thing as an "all-clear" for storms.

Please check with your local public safety officials for details on when warning sirens are sounded in your community.

My (Huttner Weather Lab) comments on sirens:

-Sirens have the advantage that everybody within earshot gets warned at once. Other warning modes depend on individual's "warning communication readiness."

-Sirens were designed and installed for "air raids" back in the Cold War days.

-The first use of sirens for tornado warnings in Minnesota is believed to be on the 1965 Twin Cities tornado outbreak.

-Sirens are designed as an "outdoor warning system."

-When you hear sirens take cover first, and seek additional information after that.

-Tornadoes can strike without a siren "warning." In Woodward, OK tornado last weekend, a lighting strike cut power to the towns 20 sirens. The tornado struck without a "siren" warning. You should have other, primary sources for warnings like NOAA Weather Radio.

So what should I do?

The bottom line is, it's up to you to decide how you will get severe weather warnings.

-Start with the "Watch!"

When a severe weather watch is issued, that's the time to ramp up your "situational awareness" of the severe weather threat that day. Make sure all of your weather sources are up and running, and check in frequently to see how severe weather is developing and moving with respect to your location. Keep the kids (and pets) at close range.

Here are several ways to make sure you get the warning.

1) NOAA Weather Radio - programmable for your location. Tone alert will wake you at night1

2) TV & Radio: Still a great way to get breaking weather news and warnings.

3) Weather Apps: Here are some free weather apps for your smartphone. Here are some more (some have a fee)

4) In your car? Know your county! When you hear a warning, take a moment to think of the best, nearest safe shelter. Get there and go inside.

5) Use common sense. Does the sky look black? Green? Hail nearby? Don't wait for a warning. Trust your senses and get to safe shelter.

Rain moves in:

Radars are lighting up today with ran in southern Minnesota. A cool soaking rain is just what we need to help ease ongoing drought.

Models crank out around .50"+ south of the metro with this system. The Twin Cities will lie on the northern edge, and I thnk about .20" is closer to reality...with the north metro tallying even less rain and little or no rain north of the metro.

Source: ISU

After a cool sunny Friday, the next shot of rain rolls in Saturday. Sunday looks like the sunnier, nicer day this weekend with highs climbing back to the 60s.

Source: NWS

Warmer next week!

A slow steady warming trend kicks in Monday & Tuesday. By Wednesday, a warm front could allow temps to soar toward the 80 degree mark in southern MN.

Source: ISU

The GFS is hinting now (for severeal runs) that waves of low pressure may move in Thursday & Friday. With heat and humidity around, it appears that there is a chance for some severe weather late next week.

PH

(2 Comments)

April soaker south of metro; Drought easing in parts of northern MN

Posted at 5:21 PM on April 19, 2012 by Paul Huttner

.50" to 1" doppler and rainfall reports for much of south central Minnesota

Well placed - rain is falling right over areas of "severe drought" in southern Minnesota

On the edge - Twin Cities on the northern edge of rainfall Thursday

86.75% of Minnesota listed in "drought" last week

64.62% of Minnesota listed in "drought" this week!

Drought easing - mainly in northwest & north central Minnesota

Cool wind map from NOAA's Digital Forecast Data Base here

Real time wind from NOAA:
(Note you may need Firefox or Google Chrome to view this image)
Source: NOAA

Wanted: Rainfall

This is how it sould work.

Thursday's soaking rain fell right over the "severe drought" areas in south central Minnesota.

Good soakers osuth of the metro
Source: WxUndergrond and WX Bug

Here are some rainfall totals as of late Thursday PM (and still raining) for selected southern Minnesota locations. (Data from WxUndergorund and Weather Bug sites)

New Prague .49"
Mankato .50"
Pine Island .63"
Dodge Center .89"
Ellendale .91"
New Ulm 1.42"

The rain skirted just south of the metro, with just .17" reported in Eden Prairie, Lakeville and Farmington. Little or no rain fell in the north metro.

Nipping away at the drought:

Our recent rainy (and snowy up north) pattern is nipping away at drought in parts of Minnesota.

Thursday's U.S. Drought Monitor shows a 22% decrease in drought coverage in Minnesota. The area in Minnesota listed in "moderate" to "severe" drought (D1-D2) fell from 86.75% to 64.62% last week.

Source: USDA/UNL

The areas that benefitted most are in northwest and north central Minnesota from Near Moorhead and Thief River Falls and Bemidji, east to Walker, the Iron Range, Duluth and parts of the North Shore.

Source: Duluth NWS

Here's more and a preview of Mark Seeley's Weather Talk, which will be posted here in Updraft when it clears the web on Friday morning.

Topic: Dewpoint records set, along with precipitation and snowfall records, April 15-16

"Just ahead of the rain and thunderstorms over April 15th strong southeast winds brought in warm, moist air to southern Minnesota, setting new high dewpoint records for the date. MSP tied a record from 1976 with a late afternoon dewpoint of 61 degrees F, while preliminary data indicate a new dewpoint record of 63 degrees F at Fairmont and Mankato. In addition a new dewpoint record of 64 degrees F was set at New Ulm. These values occurred just ahead of the severe thunderstorms, hail, funnel clouds, tornadoes, and strong winds which were reported last Sunday.

Many observers reported heavy precipitation on April 15th and 16th, some record-setting. MSP reported a new record with 1.19 inches, while St Cloud reported a record 1.51 inches. Others reporting new daily precipitation records included: 2.22 inches at Browns Valley; 2.11 inches at Wheaton; 2.10 inches at Pelican Rapids; 2.02 inches at Duluth; 1.97 inches at Rothsay; 1.87 inches at Babbitt; 1.85 inches at Tower; 1.71 inches at Moose Lake; 1.71 inches at Pipestone; 1.59 inches at Park Rapids; 1.53 inches at Aitkin; 1.51 inches at Grand Rapids; 1.46 inches at Spring Grove; 1.36 inches at Hibbing; and 1.14 inches at Morris.

In the far north, strong winds (50-60 mph) and significant amounts of snow were reported, with many roads closed, power outages, and numerous accidents. Several observers reported new daily record snowfall amounts for April 16th, including: Babbitt with 5 inches; Tower with 6.3 inches; Cook, Hibbing, and Bigfork with 8.0 inches; Kabetogama had a record 9.4 inches; and Orr and Chisholm received a whooping record 11 inches."

Cool start to the weekend:

Friday will feature cool temps mostly in the 50s.

Saturday brings another low pressure wave will bring a shot of showers, and ot could be cold enough to mix with for some snow from Brainerd to Duluth.

Source: NOAA/NWS

Warmer next week:

As the new week opens on Sunday, a new "kinder and gentler spring" weather pattern takes hold.

Sunshine will increase into next week, and a slow warming trend Sunday & Monday will give way to a fill blown warm up by mid week.

Temps should push into the 70s by Tuesday, and 80 degrees looks like a real possibility by Wednesday and Thursday of next week!

Source: ISU

With the heat (and some humidity) comes a thunder threat by next Thursday & Friday.

We'll have to see if parameters for severe weather come together, but at this point it looks possible.

Hang in there, it may feel like early summer around here by next week!

PH