Updraft: December 11, 2010 Archive

Update 4 am: Snow eases south, picks up later

Posted at 4:00 AM on December 11, 2010 by Paul Huttner (10 Comments)
Filed under: Blizzard, Snow, Winter storms

4 am Update:

Okay, I never can sleep during big storms anyway so here's a quick overnight update.

At 3:20am I measured 5" of snowfall in Deephaven at the weather lab. We have been under an intense band of snowfall producing 1" per hour for the past 2-3 hours in the Lake Minnetonka area.

Radar trends indicate (and the latest model runs support) a lull in snowfall working through southern Minnesota and into the south metro. There may be a let up in snowfall in some areas early Saturday morning...but I expect snowfall to fill in again as the storm reaches peak intensity Saturday.

NEXRAD shows a (temporary?) lull in snowfall working into south metro at 3:45am.

The late night NAM model cranked out an insane 28.1" snowfall total! This would rival the Halloween Mega Storm if it verifies...but I do not buy that total just yet. What we refer to as "short term radar and satellite trends" or "nowcasting" suggest a lull in the action for a few critical hours early Saturday morning that could keep snowfall totals in check.

(Click for bigger image)

For now, I am still forecasting snowfall totals of between 10" and 20" as a range for the greater metro area and much of western Wisconsin.

Still, the storm now appears to be coming in 2 or three intense waves of snowfall intensity...and the second wave late Saturday morning through midday could be the most intense. Forecast models suggest (and satellite trends may support) a period of intense snowfall with possible thundersnow producing prolific snowfall rates of up to 3" to 4" per hour spinning up toward the metro around 8-9am.

Potential "snowbursts" AM & PM?
(Click to enlarge)

If that happens we could pick up a lot of snow in a hurry!

The NAM model then suggests another lull in snowfall intensity...with another 1" to 2" per hour burst late in the afternoon.

Bottom line: The storm will come in waves, and it really doesn't matter at this point exactly how much snow falls...there will be enough snow and wind to produce blizzard to near blizzard conditions in much of southern Minnesota Saturday.

Stay tuned to MRR News stations (KNOW 91.1FM in the metro) Saturday. Craig Edwards will have hourly updates, and the latest snow totals and model runs through the morning and I will pick things up with hourly updates after noon as we follow the storm through the day.

Be safe, and enjoy the snow if you can!

PH

Evening Update:

Ice and snow progressing northeast as expected tonight. It still looks like a wintery mix could begin anywhere between about 8pm and 10pm in the metro...then change to all snow and pick up in intensity after midnight.

I set up the Twin Cities radar loop to show snow, ice and rain. Latest radar update here.

We could have 6" of snow on the ground already by early Saturday morning in many areas.

Latest model trends all support high snow totals...in the 15"+ range. I'm sticking with a forecast snow total range of 10" to 20" for the metro and western Wisconsin by Saturday evening.

Travel should be fine around the metro until 9pm or so...then al bets are off. Get home early, or be ready for snow (and maybe a little ice) if you are going to be out later tonight.

PH

Doppler Update 4:30pm :

Sioux Falls doppler showing mixed bag of rain, ice and snow busting out and moving NE into southwest Minnesota during the 4pm hour.

Moisture surge should reach the metro between 8pm & 10pm tonight. A possible wintery mix should quickly change to all snow and intensity will increase rapidly after midnight.

Just when you thought it was safe to think about maybe lowering snowfall forecasts...the 18Z (noon) NAM model run cranks out a 19" snowfall total for the metro!

That's the highest output of any numerical forecast model so far. I think that's probably on the high end of the range...but it supports the notion of a 10" to 20" forecast in the max snowfall band.

PH

All systems are go for a MAJOR winter storm in Minnesota tonight and Saturday.

It looks like this storm will deserve all the pre-storm hype we can pile on, as a powerful mix of snow, wind and bitter cold locks in over Minnesota and the Upper Midwest this weekend.

Here's the latest (and hopefully best) thinking at this point...and some headlines on the storm.

-Winter storm warnings are up for the metro, blizzard warnings for much of SW MN, inclding counties just southwest of the metro!

Winter storm warnings are flying for the metro. Blizzard warnings include Mankato, Redwood Falls, Marshall and Worthington.

-The biggest emphasis and IMPACTS with this storm will be heavy snow, wind causing severe blowing and drifting snow, and bitter cold behind the storm. There may be near blizzard conditons in much of Minnesota Saturday and Saturday night! We all love to focus on inches...but travel conditons will be the same (travel difficult to impassable) Saturday regeardless of 10" or 20" of total snowfall.

-Snow will spread into SW Minnesota this afternoon, and should begin in the metro sometime between 9pm and midnight.

-The snow will pick up in intensity after midnight, and snowfall rates could exceed 1" per hour from midnight through about 9-10 am Saturday. There could be convective snowbursts or "thundersnow" with this storm overnight into early Saturday. Snowfall rates can approach 2" to 3" per hour in thundersnow.

Nam model snowfall output indicating 1"+ per hour for many hours...and a total of 18.9"!
(Click for much more easily readable image)

-Snow will continue through much of Saturday PM before winding down late PM.

-Strong winds between 25 and 40 mph will kick up Saturday into Saturday night, causing severe blowing and drifting of relatively dry powdery snowfall. There will be blizzard or near blizzard conditions in much of Minnesota Saturday and Saturday night. (Blizzard criteria = sustained winds of 35 mph and visibilities at or under 1/4 mile in falling or blowing snow.)

-The storm will likely mix with freezing rain along the I-90 corridor...and sleet in south central Minnesota.

-Storm total snowfall accumulations could approach 10" to 20" for much of east central Minnesota and western Wisconsin by late Saturday...including the Twin Cities metro area. This has the potential to be the biggest snowfall since the Halloween Mega storm in 1991 for some locations.

NAM model continues to lay out the heaviest snow band (up to 16"+?) right across the Twin Cities metro Saturday.

Model runs with "Cobb Technique" snowfall output...10" to 18"?

This will be a major winter storm...and possibly (hopefully!) the biggest storm this winter season. I expect travel to be extremely difficult (impassable?) outside the metro by Saturday PM & evening. I also expect numerous road closures and MNDOT may have to pull plows off the roads Saturday in some areas.

A top 10 storm?

For the record, I do not think this storm has the capacity to rival the Halloween Mega Storm for overall snowfall totals.

But, if we get 15" in the metro with this storm, it would be the 11th biggest snowstorm in Twin Cities history. Here are the top snow storms in Twin Cities history courtesy of the Minnesota Climate Working Group.

Top Thirteen Largest Snowfalls for Twin Cities:

1. 28.4 inches: October 31 - November 3, 1991 (Halloween Blizzard)
2. 21.1 inches: November 29 - December 1, 1985
3. 20.0 inches: January 22 - January 23, 1982
4. 17.4 inches: January 20 - January 21, 1982
5. 16.8 inches: November 11 - November 12, 1940 (Armistice Day)
6. 16.7 inches: March 3 - March 4, 1985
7. 16.7 inches: March 11 - March 14, 1940
8. 16.5 inches: December 27 - December 28, 1982
9. 16.0 inches: January 20 - January 21, 1917
10. 16.0 inches: March 8 - March 9, 1999
11. 14.7 inches: March 31, 1985
12. 14.3 inches: November 29 - November 30, 1991
13. 14.1 inches: March 22 - March 23, 1952

If the snow total with this storm exceed 16" it will in fact be the biggest snow since the Halloween Mega Strom of 1991. That's a tall order, but it looks like at least possibility with this storm. A 15" snowfall would make this the biggest snow in the metro in 11 years, since March of 1999.

Bottom line: A major winter storm will bring snow, wind and then bitter cold to Minnesota during the next 48 hours. Be ready!

PH

(10 Comments)

Epic Snow: Shakopee 21.5" Wind/cold Sunday

Posted at 10:30 PM on December 11, 2010 by Paul Huttner (9 Comments)
Filed under: Snow, Winter storms

Highest storm total: Shakopee 21.5"
Lowest metro total: Waconia & Champlin at 9.9"

It appears metro snowfall totals ranged from 9.9" to 21.5".

The 16.5" total at MSP Airport is officially the biggest snowfall since the Halloween Mega Storm in 1991, and the 8th largest snowfall on record in the Twin Cities. It could move higher on the list, pending a final snow total at MSP from NWS.

Top Snowfalls for Twin Cities

1. 28.4 inches: October 31 - November 3, 1991 (Halloween Blizzard)
2. 21.1 inches: November 29 - December 1, 1985
3. 20.0 inches: January 22 - January 23, 1982
4. 17.4 inches: January 20 - January 21, 1982
5. 16.8 inches: November 11 - November 12, 1940 (Armistice Day)
6. 16.7 inches: March 3 - March 4, 1985
7. 16.7 inches: March 11 - March 14, 1940
8. 16.5 inches: December 27 - December 28, 1982
9. 16.0 inches: January 20 - January 21, 1917
10. 16.0 inches: March 8 - March 9, 1999
11. 14.7 inches: March 31, 1985

Latest snowfall totals below:

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
906 PM CST SAT DEC 11 2010

...PRELIMINARY SNOWFALL TOTALS FROM FRIDAY NIGHT THROUGH SATURDAY...

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.

**NOTE: DUE STRONG WINDS THERE HAS BEEN CONSIDERABLE DRIFTING
SNOW...AND THEREFORE SNOWFALL OBSERVATIONS WERE HIGHLY VARIABLE.
A GREAT DEAL OF ESTIMATING WENT INTO THESE SNOWFALL REPORTS.

SNOW REPORTS LISTED BY AMOUNT

INCHES LOCATION ST COUNTY TIME
------ ----------------------- -- -------------- -------
21.50 SHAKOPEE MN SCOTT 0654 PM
20.00 OAKDALE MN WASHINGTON 0247 PM
18.10 RED WING MN GOODHUE 0812 PM
18.00 EAST FARMINGTON WI POLK 0630 PM
18.00 3 SSW BURNSVILLE MN DAKOTA 0610 PM
18.00 MENOMONIE WI DUNN 0346 PM
17.50 RED WING MN GOODHUE 0506 PM
17.40 NEW RICHMOND WI ST. CROIX 0516 PM
17.40 LAKEVILLE MN DAKOTA 0906 PM
17.20 4 SSW MINNEAPOLIS MN HENNEPIN 0520 PM
17.00 2 N MENOMONIE WI DUNN 0620 PM
17.00 MAPLEWOOD MN RAMSEY 0334 PM
16.50 MINNEAPOLIS MN HENNEPIN 0600 PM
MEASURED AT THE MINNEAPOLIS/ST. PAUL
INTERNATIONAL AIRPORT. STORM TOTAL SO FAR.
16.30 HASTINGS MN DAKOTA 0826 PM
16.10 BLOOMINGTON MN HENNEPIN 0607 PM
15.50 EDINA MN HENNEPIN 0554 PM
15.20 CHANHASSEN MN CARVER 0600 PM
MEASURED AT THE NWS OFFICE IN CHANHASSEN.
STORM TOTAL SO FAR.
15.20 ST PAUL MN RAMSEY 0429 PM
15.20 WOODBURY MN WASHINGTON 0230 PM
15.00 1 SSW DELANO MN WRIGHT 0620 PM
14.00 6 NW RICE LAKE WI BARRON 0504 PM
14.00 WYOMING MN CHISAGO 0452 PM
14.00 EAU CLAIRE WI EAU CLAIRE 0410 PM
14.00 HASTINGS MN DAKOTA 0316 PM
14.00 PRIOR LAKE MN SCOTT 0309 PM
13.50 1 ESE CHASKA MN CARVER 0700 PM
13.50 ELK MOUND WI DUNN 0655 PM
13.50 3 WNW LADYSMITH WI RUSK 0415 PM
13.00 LAKEVILLE MN DAKOTA 0334 PM
12.90 1 SW ST PAUL MN RAMSEY 0214 PM
12.80 STANLEY WI CHIPPEWA 0520 PM
12.50 1 ENE CAMBRIDGE MN ISANTI 0630 PM
12.00 ISANTI MN ISANTI 0424 PM
12.00 RICHFIELD MN HENNEPIN 0418 PM
12.00 NEW BRIGHTON MN RAMSEY 0243 PM
12.00 FARIBAULT MN RICE 0909 PM
11.70 ST LOUIS PARK MN HENNEPIN 0249 PM
11.50 1 SE NORTHFIELD MN RICE 0350 PM
11.50 JIM FALLS WI CHIPPEWA 0119 PM
11.00 NORTH BRANCH MN CHISAGO 0218 PM
10.50 HUTCHINSON MN MCLEOD 0345 PM
9.90 CHAMPLIN MN HENNEPIN 0430 PM
9.90 WACONIA MN CARVER 0300 PM
9.50 ISANTI MN ISANTI 0158 PM
8.50 ANDOVER MN ANOKA 1225 PM
8.00 MANKATO MN BLUE EARTH 0715 PM
8.00 HAUGEN WI BARRON 0332 PM
7.00 4 S ST CLOUD MN STEARNS 0635 PM
6.00 WINTHROP MN SIBLEY 0820 PM
6.00 LITCHFIELD MN MEEKER 0415 PM
3.20 MURDOCK MN SWIFT 0310 PM

Evening Update:

Evening radar trends show snowfall winding down from northwest to southeast tonight. The storm is beginning to pull away, but not before dumping 15" to 20" in most of the metro and western Wisconsin.

Storm makes history:

This will go down as one of the top snowfall producers in Twin Cities' history.

The 16.5" total at MSP Airport is officially the biggest snowfall since the Halloween Mega Storm in 1991.

The "epicenter" for the heaviest snowfall is in the heart of the metro... from Minneapolis through St. Paul...the east metro into western Wisconsin.

Here is the latest snowfall summary from NWS as the falling snow winds down in the metro tonight. You can check individual totals as they come in here.

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
655 PM CST SAT DEC 11 2010

...PRELIMINARY SNOWFALL REPORTS FROM STORM...

THE TOTALS BELOW ARE NOT NECESSARILY THE FINAL AMOUNT FOR EACH LOCATION.

**NOTE: DUE STRONG WINDS THERE HAS BEEN CONSIDERABLE DRIFTING
SNOW...AND THEREFORE SNOWFALL OBSERVATIONS WERE HIGHLY VARIABLE.
A GREAT DEAL OF ESTIMATING WENT INTO THESE SNOWFALL REPORTS.

SNOW REPORTS LISTED BY AMOUNT

INCHES LOCATION ST COUNTY TIME
------ ----------------------- -- -------------- -------
20.00 OAKDALE MN WASHINGTON 0247 PM
18.00 MENOMONIE WI DUNN 0346 PM
18.00 SHAKOPEE MN SCOTT 0341 PM
18.00 FARMINGTON MN DAKOTA 0630 PM
18.00 3 SSW BURNSVILLE MN DAKOTA 0610 PM
17.50 RED WING MN GOODHUE 0506 PM
17.40 NEW RICHMOND WI ST. CROIX 0516 PM
17.20 4 SSW MINNEAPOLIS MN HENNEPIN 0520 PM
17.00 MAPLEWOOD MN RAMSEY 0334 PM
16.50 MINNEAPOLIS MN HENNEPIN 0600 PM
MEASURED AT THE MINNEAPOLIS/ST. PAUL
INTERNATIONAL AIRPORT. STORM TOTAL
SINCE FRIDAY NIGHT
16.10 1 W BLOOMINGTON MN HENNEPIN 0607 PM
15.50 EDINA MN HENNEPIN 0554 PM
15.20 BLOOMINGTON MN HENNEPIN 0440 PM
15.20 ST PAUL MN RAMSEY 0429 PM
15.20 WOODBURY MN WASHINGTON 0230 PM
15.20 CHANHASSEN MN CARVER 0600 PM
OFFICIAL NWS OBSERVATION
15.00 1 SSW DELANO MN WRIGHT 0620 PM
14.00 6 NW RICE LAKE WI BARRON 0504 PM
14.00 WYOMING MN CHISAGO 0452 PM
14.00 EAU CLAIRE WI EAU CLAIRE 0410 PM
14.00 HASTINGS MN DAKOTA 0316 PM
14.00 PRIOR LAKE MN SCOTT 0309 PM
13.50 3 WNW LADYSMITH WI RUSK 0415 PM
13.00 LAKEVILLE MN DAKOTA 0334 PM
12.90 1 SW ST PAUL MN RAMSEY 0214 PM
12.80 STANLEY WI CHIPPEWA 0520 PM
12.00 ISANTI MN ISANTI 0424 PM
12.00 RICHFIELD MN HENNEPIN 0418 PM
12.00 NEW BRIGHTON MN RAMSEY 0243 PM
11.70 ST LOUIS PARK MN HENNEPIN 0249 PM
11.50 1 SE NORTHFIELD MN RICE 0350 PM
11.00 NORTH BRANCH MN CHISAGO 0218 PM
10.50 HUTCHINSON MN MCLEOD 0345 PM
9.90 CHAMPLIN MN HENNEPIN 0430 PM
9.90 WACONIA MN CARVER 0300 PM
7.00 MANKATO MN BLUE EARTH 0430 PM
6.00 LITCHFIELD MN MEEKER 0415 PM

Top Snowfalls for Twin Cities

1. 28.4 inches: October 31 - November 3, 1991 (Halloween Blizzard)
2. 21.1 inches: November 29 - December 1, 1985
3. 20.0 inches: January 22 - January 23, 1982
4. 17.4 inches: January 20 - January 21, 1982
5. 16.8 inches: November 11 - November 12, 1940 (Armistice Day)
6. 16.7 inches: March 3 - March 4, 1985
7. 16.7 inches: March 11 - March 14, 1940
8. 16.5 inches: December 27 - December 28, 1982
9. 16.0 inches: January 20 - January 21, 1917
10. 16.0 inches: March 8 - March 9, 1999
11. 14.7 inches: March 31, 1985

Overall, the storm produced between 10" and 20" of snow in and around the greater Twin Cities metro, with lower amounts to the north and still counting in southeast Minnesota overnight.

Blizzard Update:

Blizzard conditions will continue in much of southwest and south central MN overnight. Blizzard warnings continue in effect into Sunday morning from the southern metro south to the Iowa border.

Many (most) roads are closed form the metro south and west tonight. MNDOT is recommending no travel...it would be foolish to attempt travel tonight anywhere south of the (and even in) metro. With falling temps, reduced visibilities in blowing snow, and wind chills well below zero, conditions will be rapidly life threatening to anyone caught outside overnight!

Winds gusts as high as 64 mph have ripped across the open country in southern Minnesota today. MNDOT sensors recorded a wind gust of 64 at Rushmore along I-90 today. Full blown blizzard criteria have been reached and exceeded at Worthington and Marshall for much of the day, with winds gusting as high as 56 mph in Worthington and visibilities near 0 in whiteout conditions at times!

Remember the criteria for blizzard conditions from AMS.

blizzard--A severe weather condition characterized by high winds and reduced visibilities due to falling or blowing snow.
The U.S. National Weather Service specifies a wind of 30 knots (35 miles per hour) or greater, sufficient snow in the air to reduce visibility to less than 400 m (0.25 miles).

With sustained winds of 45 mph and gusts to 64 with near 0 visibilities for hours...this was an "Uber Blizzard" for much of southwest Minnesota.

Snow drifts of 3 feet are reported at Mankato and 3-4 feet near Rice Lake, WI. With the wind overnight, I expect snow drifts of 3 to 5+ feet in open areas by Sunday morning.

Anatomy of a Superblizzard:

This storm was a rapidly deepening low pressure system. Notice the classic "comma shaped" circulation and precip pattern wrapped around the northwest side of the surface low as it moves out of eastern Iowa. Also notice the tight pressure gradient over southern Minnesota...generating near hurricane force gusts and sustained blizzard conditions.

This is (hopefully) a once in more than a decade storm for Minnesota!

PH

Update 4:30pm:

MNDOT reports a wind gust of 64 mph in Rushmore along I-90 in southern Minnesota! That's a full blown severe thunderstorm level gust, and just 10 mph shy of hurricane force.

Latest snowfall totals include:

Oakdale 20"
Shakopee 18"
Menomonie 18"
Maplewood 17"
MSP Airport 14.6"
Hastings 14"
Richfield 12"
Hutchinson 10.5"

Latest radar trends show back edge of snowfall from near St. Cloud to Willmar...collapsing slowly SE. Still moderate to heavy snow in the metro...and a ferocious snow burst from Red Wing to Northfield and Zumbrota...heading for Rochester.

Expect 3-5 more hours of snow in metro..and snow after midnight in SE MN. Followed by increasing wind with blowing and drifting snow!

PH

Update 3:15pm:

Breaking news: An incredible 20" snowfall total is reported by a trained spotter in Oakdale east of St. Paul! Woodbury reoprts 15.2"! MSP Airport 14.6"!

0247 PM SNOW OAKDALE E20.0 INCH TRAINED SPOTTERSTORM TOTAL SO FAR...ESTIMATED 9 INCHES IN THE PAST 4 HOURS.

Twin Cities Airport is likey to reach at least 16.1" snowfall total. If that happens, this will be the biggest snowfall event since the infamous Halloween Mega Storm in 1991!

Top Snowfalls for Twin Cities

1. 28.4 inches: October 31 - November 3, 1991 (Halloween Blizzard)
2. 21.1 inches: November 29 - December 1, 1985
3. 20.0 inches: January 22 - January 23, 1982
4. 17.4 inches: January 20 - January 21, 1982
5. 16.8 inches: November 11 - November 12, 1940 (Armistice Day)
6. 16.7 inches: March 3 - March 4, 1985
7. 16.7 inches: March 11 - March 14, 1940
8. 16.5 inches: December 27 - December 28, 1982
9. 16.0 inches: January 20 - January 21, 1917
10. 16.0 inches: March 8 - March 9, 1999
11. 14.7 inches: March 31, 1985

Storm near peak intensity now with heavy snow in southern half of Minnesota... and blizzard conditions in southwest Minnesota.

Twin Cities Metro

CITY SKY/WX TMP DP RH WIND PRES REMARKS
TWIN CITIES HVY SNOW 21 18 88 N24G33 29.82R VSB 1/8 WCI 4

Southwest Minnesota

CITY SKY/WX TMP DP RH WIND PRES REMARKS
MONTEVIDEO LGT SNOW 10 9 92 N30G37 30.03R WCI -12
GRANITE FALLS SNOW 11 8 85 NW28G36 30.02R VSB 1/2 WCI -10
CANBY SNOW 6 3 88 NW28G44 30.09R VSB 1/4 WCI -17
MARSHALL CLOUDY 7 1 78 N35G45 29.98R VSB<1/4 WCI -18
REDWOOD FALLS FOG 13 10 88 N20G36 29.92R VSB 1/4 WCI -5
OLIVIA CLOUDY 16 12 86 N23G32 29.96R WCI -2
PIPESTONE N/A 7 3 85 N28G43 29.90R WCI -16
WINDOM HVY SNOW 10 10 100 N32G39 29.78R VSB<1/4 WCI -12
WORTHINGTON CLOUDY N/A N/A N/A N45G54 29.80R VSB<1/4
JACKSON HVY SNOW 14 14 100 N16G29 29.73R VSB<1/4 WCI -2
TRACY HVY SNOW 8 5 86 N28G40 29.92R VSB<1/4 WCI -14
SLAYTON HVY SNOW 7 4 89 N29G39 29.86R VSB<1/4 WCI -16

Latest snowfall totals include:

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
222 PM CST SAT DEC 11 2010

..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..

0220 PM SNOW 4 SSW MINNEAPOLIS M14.9 INCH TRAINED SPOTTER STORM TOTAL... SO FAR

0214 PM SNOW 1 SW ST PAUL M12.9 INCH TRAINED SPOTTER
HIGHLAND PARK AREA... STORM TOTAL... SO FAR

From the latest Twin Cities NWS forecast discussion: QUITE SIMPLY...ITS A TRAVEL NIGHTMARE ACROSS MOST OF SOUTHERN MN AND WESTERN WI. MANY AIRPORTS REPORTING 1/4SM +SN....THE AIRPORT HAS RECORDED CLOSE TO A FOOT OF
SNOW AS OF 12 PM CST. ANOTHER 3-6 INCHES IS LIKELY BEFORE THE SNOW
DIMINISHES EARLY THIS EVENING. WIND GUSTS OVER 20KTS WILL LINGER
WELL PAST 06Z TONIGHT.

I expect another 3" to 5" in most areas of the Twin Cities before snow begins to taper off this evening. That will bring storm totals into the 14" to 20" range in most areas of the metro.

Blizzard conditions will continue through tonight in southwest & south central Minnesota.

If Twin Cities Airport gets 16.1" it will be the biggest snow storm since the Halloween Mega Storm of 1991.

We have a shot...stay tuned!

PH

Update 1:30pm:

Snowfall totals now at or over 1 foot in the metro!

1231 PM SNOW SHAKOPEE M13.0 INCH TRAINED SPOTTER

MNDOT traffic cams and my observations conclude....attempt travel only in emergencies...and at great risk of getting stranded...even in the metro.

MNDOT reports many freeway exit ramps impassable in the metro.

Cars stranded on entrance ramp at Highway 169 & I- 494

Snowfall totals will likely reach 16" to 20" in some parts of the metro.

Snow approaching 11" at the Huttner Weather Lab in west metro.

Reduced visibility in wind and blowing snow in west metro.

Blizzard conditions continue in southwest Minnesota. Winds gusts of 58 mph have been recorded in Worthington! That's a severe thunderstorm strength wind.

Southwest Minnesota

CITY SKY/WX TMP DP RH WIND PRES REMARKS
MONTEVIDEO LGT SNOW 12 9 85 N28G39 30.01R VSB 3/4 WCI -9
GRANITE FALLS SNOW 12 8 85 NW30 29.99R VSB 1/2 WCI -10
CANBY SNOW 7 4 88 NW30G40 30.06R VSB 1/4 WCI -17
MARSHALL CLOUDY 9 3 78 N35G43 29.95R VSB<1/4 WCI -15
REDWOOD FALLS FOG 14 11 87 N25G33 29.88R VSB 1/4 WCI -5
OLIVIA N/A 16 12 86 N25G40 29.90R WCI -3
PIPESTONE N/A 7 3 85 N29G36 29.87R WCI -16
WINDOM HVY SNOW 16 12 86 N35G41 29.75R VSB<1/4 WCI -6
WORTHINGTON CLOUDY N/A N/A N/A N46G56 29.77R VSB<1/4
JACKSON HVY SNOW 16 14 93 N17G31 29.70R VSB<1/4 WCI 0
TRACY HVY SNOW 9 6 87 N30G41 29.89R VSB<1/4 WCI -13
SLAYTON HVY SNOW 7 5 89 N30G39 29.84R VSB<1/4 WCI -16

Update 12:30pm:

Storm nearing peak intensity next 3-6 hours.

Doppler Update:

Heavy snow bands on radar rotating through from Mankato up the Minnesota River Valley into the metro now. Snowfall rates in the heavy snow band at 1" to 2" per hour.

Visibilities:

One way to measure snowfall intensity is by visibility, especially where winds are still relatively lighter such as in the metro now. Metro observations now reporting heavy snow with visibilities of 1/4 to 1/8 mile. That corresponds to snowfall rates of 1" to 2" per hour!

CITY SKY/WX TMP DP RH WIND PRES REMARKS

TWIN CITIES HVY SNOW 21 18 88 N21G29 29.82F VSB 1/8 WCI 5
6HR MIN TEMP: 20; 6HR MAX TEMP: 21; 6HR PCP: 0.46;
ST PAUL FOG 21 19 92 N17G66 29.84F VSB 1/4 WCI 7
CRYSTAL HVY SNOW 22 17 81 N15G26 29.84S VSB 1/4 WCI 9
BLAINE SNOW 21 19 93 N20G33 29.85S VSB 1/2 WCI 6
EDEN PRAIRIE FOG 21 19 92 N18G30 29.79S VSB 1/4 WCI 6
6HR MIN TEMP: 20; 6HR MAX TEMP: 22; 6HR PCP: 0.09;
LAKEVILLE SNOW 21 19 93 NE17G30 29.76F VSB 1/2 WCI 7
SOUTH ST PAUL SNOW 23 20 90 N17G25 29.81F VSB 1/2 WCI 9
LAKE ELMO HVY SNOW 21 18 86 N18G25 29.81F VSB<1/4 WCI 6

Blizzard conditions now:

There is a full blow blizzard in southwest Minnesota right now. Winds sustained at 35mph...and visibilities under 1/4 mile in heavy falling and or blowing snow. Blizzard warnings now extend right up into the south and west metro!

Southwest Minnesota

CITY SKY/WX TMP DP RH WIND PRES REMARKS
MONTEVIDEO LGT SNOW 12 9 85 NE26G37 30.01R VSB 3/4 WCI -8
GRANITE FALLS SNOW 12 8 87 NW26G35 29.98S VSB 1/4 WCI -9
CANBY SNOW 7 4 88 NW26G39 30.04R VSB 1/4 WCI -16
MARSHALL CLOUDY 9 3 78 N36G44 29.92R VSB<1/4 WCI -16
REDWOOD FALLS FOG 16 13 88 N26G40 29.86S VSB 1/4 WCI -3
OLIVIA N/A 18 14 86 N40G48 29.89S WCI -4
PIPESTONE N/A N/A N/A N/A N29G38 29.84R
WINDOM HVY SNOW 14 12 92 N32 29.74R VSB<1/4 WCI -7
WORTHINGTON CLOUDY N/A N/A N/A N44G58 29.74R VSB<1/4
JACKSON HVY SNOW 16 14 93 N18G24 29.67R VSB<1/4 WCI -1
TRACY HVY SNOW 10 7 88 N31G38 29.88R VSB<1/4 WCI -12
SLAYTON HVY SNOW N/A N/A N/A N28G35 29.82R VSB<1/4

Visibilities are likely near 0 now in many SW Minnesota communities. I-90 is closed...it's just too dangerous to send the plows out in this extreme of wind and snow. Do not travel today if you don't have to! It's juts plain stupid, even for us "hearty Minnesotans."

Snowfall totals:

We have exceeded 1 foot of snow in the Twin Cities just after noon.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1217 PM CST SAT DEC 11 2010

..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..

1231 PM SNOW SHAKOPEE 12/11/2010 M13.0 INCH TRAINED SPOTTER

1200 PM SNOW MINNEAPOLIS 44.96N 93.27W
12/11/2010 M11.7 INCH OFFICIAL NWS OBS

STORM TOTAL AT KMSP AIRPORT...WITH 0.79 INCH LIQUID
EQUIVALENT. 6.8 INCHES IN THE LAST 6 HOURS. SNOW DRIFTS
BETWEEN 2 AND 3 FEET.

1221 PM SNOW CHANHASSEN 44.86N 93.56W
12/11/2010 M11.4 INCH CARVER MN OFFICIAL NWS OBS
STORM TOTAL MEASURED AT THE NWS OFFICE IN CHANHASSEN.

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
1150 AM CST SAT DEC 11 2010

...PRELIMINARY SNOWFALL TOTALS FROM SATURDAY...

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
------ ----------------------- -- -------------- -------
11.00 OAKDALE MN WASHINGTON 1014 AM
10.50 SHAKOPEE MN SCOTT 1015 AM
10.00 STILLWATER MN WASHINGTON 1131 AM
10.00 2 N MENOMONIE WI DUNN 1118 AM
10.00 NEW HOPE MN HENNEPIN 1028 AM
9.70 ST PAUL MN RAMSEY 1114 AM
MEASURED IN THE HIGHLAND PARK AREA.
9.70 WOODBURY MN WASHINGTON 1027 AM
8.50 MONTEVIDEO MN CHIPPEWA 1149 AM
8.50 2 S PRIOR LAKE MN SCOTT 1040 AM
8.20 EAU CLAIRE WI EAU CLAIRE 1119 AM
8.20 RICHFIELD MN HENNEPIN 1114 AM
8.00 1 S RICE LAKE WI BARRON 1003 AM
8.00 1 SSW DELANO MN WRIGHT 0915 AM
7.80 MAPLE GROVE MN HENNEPIN 1106 AM
7.80 HASTINGS MN DAKOTA 1105 AM
7.60 3 SSW MINNEAPOLIS MN HENNEPIN 1025 AM
7.50 ST PAUL MN RAMSEY 0935 AM
MEASURED AT SNELLING AND RANDOLPH.
7.20 MENOMONIE WI DUNN 0920 AM
7.10 MINNEAPOLIS MN HENNEPIN 0900 AM
MEASURED AT THE MSP AIRPORT.
7.10 2 SW ST PAUL MN RAMSEY 0841 AM
7.00 BROWNTON MN MCLEOD 1016 AM
7.00 OSCEOLA WI POLK 0655 AM
6.50 MINNETONKA MN HENNEPIN 1004 AM
6.50 BURNSVILLE MN DAKOTA 0932 AM
6.30 6 NW RICE LAKE WI BARRON 0754 AM
6.10 LONG LAKE MN HENNEPIN 0800 AM
6.10 WACONIA MN CARVER 0712 AM
6.00 STANLEY WI CHIPPEWA 0920 AM
5.30 RAMSEY MN ANOKA 0651 AM
5.20 EDINA MN HENNEPIN 0848 AM
5.20 JIM FALLS WI CHIPPEWA 0701 AM
5.00 ISANTI MN ISANTI 0957 AM
5.00 RICE LAKE WI BARRON 0711 AM
4.60 5 S RED WING MN GOODHUE 0804 AM
4.30 WYOMING MN CHISAGO 0701 AM
4.00 ELLENDALE MN STEELE 1040 AM
3.50 ST CLAIR MN BLUE EARTH 1021 AM
3.00 MANKATO MN BLUE EARTH 1105 AM
3.00 ST CLAIR MN BLUE EARTH 0819 AM
2.50 ST JAMES MN WATONWAN 0830 AM
2.40 RUSH CITY MN CHISAGO 0754 AM
2.00 SPRINGFIELD MN BROWN 1107 AM
2.00 CARLOS MN DOUGLAS 0932 AM
2.00 SAUK RAPIDS MN BENTON 0807 AM
2.00 WINTHROP MN SIBLEY 0749 AM
1.80 DONNELLY MN STEVENS 1041 AM
1.20 8 S HILLMAN MN MORRISON 0900 AM

Additional snowfall:

We'll likely see another 6 hours of moderate to heavy snow for the metro...more in western Wisconsin and southeast Minnesota. At rates of 1" to 2" per hour, that's another 6" to 10" of snow for some locations.

Expect final snow totals in the 10" to 20" range for much of the metro and southern Minnesota, and western Wisconsin! There will likely be a 20" total somewhere in the metro...making this the biggest Twin Cities' snowfall since the Halloween Mega Storm in 1991.

Stay safe!

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