First, this is not meant to scare you or anything, just to let you know about the possibilities of an large upcoming storm that could wreck havoc over the Christmas period for travel.
Within the past day or so, the computer models have started coming together and placing a possible snowstorm over southern Minnesota and the St. Cloud area from Wednesday Evening through Christmas. The models have the low of the storm passing somewhere between Chicago and southeast Minnesota, and bring a sizable amount of snow to the area. Right now the models are outputting as much as 20" over the Twin Cities (12z GFS Cobb, picture). The best estimate, though, is a good 6-12" of snow with even more possible.
A few factors are in favor for a large snow total. First, a favorable track has some of the heaviest snow over the area. Already, they are warning in the Sioux City area of 10-20" of snow from the storm. It would be that type of snow that lifts northward into our area. Also, the Gulf of Mexico will be open for moisture, allowing a wet snow to accumulate with a) snow-to-liquid ratios between 10-15:1, and b) liquid amounts possibly over 1".
I still have some worries about the storm though. First, the track is still very uncertain. We are still a number of days away from the storm, and the track could change by then. Also, the first surge of snow on Wednesday Night will have a warm factor to it, which could mean there is a mixture of sleet. It looks like, though, that that portion may only make it to the Rochester area, so that we will still see an entire snow event.
Right now, the system will come in three parts. First will be Wednesday into Wednesday Night. Next part will be later Thursday through Christmas Morning, and the third while the storm is departing late Friday into Saturday Morning. Also, especially from Thursday onward, winds will pick up from the north at 20-30 mph, creating some blowing and drifting.
Again, the best estimate could only be up to a foot of snow, but it will be redefined as we get closer to the storm date. Stay tuned as this storm will likely wreck havoc on many travel plans starting Wednesday.
URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
351 PM CST MON DEC 21 2009
...FAST MOVING STORM SYSTEM BRINGING LIGHT SNOW TO SOUTHERN
MINNESOTA OVERNIGHT...
...WINTER STORM WATCH FOR CENTRAL AND SOUTHERN MINNESOTA...AND
PORTIONS OF WEST CENTRAL WISCONSIN STARTING WEDNESDAY AFTERNOON...
.A FAST MOVING...BUT POTENT WINTER WEATHER SYSTEM WILL BRING A
PERIOD OF LIGHT TO MODERATE SNOWFALL OVERNIGHT ACROSS PORTIONS OF
SOUTHERN MINNESOTA...WITH THE HEAVIEST ACCUMULATIONS ALONG THE
IOWA BORDER.
A MORE SIGNIFICANT STORM SYSTEM IS EXPECTED TO IMPACT THE UPPER
MIDWEST STARTING WEDNESDAY AFTERNOON...AND LASTING THROUGH FRIDAY.
DUE TO THE STRENGTH OF THIS SYSTEM AND THE PROLONGED PERIOD FOR
WHICH THE SNOWFALL IS EXPECTED...THERE WILL BE MAJOR IMPACTS TO
TRAVELERS...ESPECIALLY DUE TO THE UPCOMING HOLIDAY.
ALTHOUGH THERE REMAINS SOME MINOR TIMING ISSUES AND THE EXACT
STORM TRACK IS STILL UNCLEAR...THE LARGE NATURE OF THIS
SYSTEM...AND EXPECTED HIGH ENERGY AND MOISTURE CONTENT...WILL
LEAD TO A BROAD AREA OF HEAVY SNOW...SLEET AND FREEZING RAIN
ACROSS THE UPPER MIDWEST. THIS STORM SYSTEM IS SO COMPLEX THAT
WILL BE THREE BOUTS OF PRECIPITATION WITH THIS EVENT. THE FIRST IS
EXPECTED TO DEVELOP WEDNESDAY AFTERNOON AND SPREAD NORTHWARD
ACROSS THE UPPER MIDWEST. THIS WAVE HAS ABUNDANT WARM AIR
ASSOCIATED WITH IT...SO THERE WILL BE A MIXTURE OF SLEET AND
FREEZING RAIN AS FAR NORTH AS THE IOWA BORDER. THE NEXT WAVE IS
EXPECTED TO IMPACT THE AREA THURSDAY AFTERNOON THROUGH EARLY
FRIDAY MORNING WITH WIND SPEEDS INCREASING FROM THE NORTH. THE
LAST WAVE WILL LIKELY BE THE WRAP AROUND MOISTURE WHICH WILL OCCUR
FRIDAY AFTERNOON AS THE STORM SYSTEM BEGINS TO DEPART THE REGION.
AS THE STORM SYSTEM APPROACHES...SNOWFALL AMOUNTS WILL BE FURTHER
REFINED...BUT TOTAL ACCUMULATIONS COULD EXCEED A FOOT OVER PARTS
MINNESOTA AND WISCONSIN. GIVEN THE TIMING OF THIS SYSTEM...HOLIDAY
ROAD AND AIR TRAVEL WILL BE SIGNIFICANTLY IMPACTED.
MNZ041>045-047>063-065>070-076>078-WIZ014>016-023>028-220600-
/O.NEW.KMPX.WS.A.0008.091224T0000Z-091226T0000Z/
DOUGLAS-TODD-MORRISON-MILLE LACS-KANABEC-STEVENS-POPE-STEARNS-
BENTON-SHERBURNE-ISANTI-CHISAGO-LAC QUI PARLE-SWIFT-CHIPPEWA-
KANDIYOHI-MEEKER-WRIGHT-HENNEPIN-ANOKA-RAMSEY-WASHINGTON-RENVILLE-
MCLEOD-SIBLEY-CARVER-SCOTT-DAKOTA-LE SUEUR-RICE-GOODHUE-POLK-
BARRON-RUSK-ST. CROIX-PIERCE-DUNN-PEPIN-EAU CLAIRE-
INCLUDING THE CITIES OF...ALEXANDRIA...LONG PRAIRIE...
LITTLE FALLS...PRINCETON...MORA...MORRIS...GLENWOOD...ST. CLOUD...
FOLEY...ELK RIVER...CAMBRIDGE...CENTER CITY...MADISON...BENSON...
MONTEVIDEO...WILLMAR...LITCHFIELD...MONTICELLO...MINNEAPOLIS...
BLAINE...ST. PAUL...STILLWATER...OLIVIA...HUTCHINSON...GAYLORD...
CHASKA...SHAKOPEE...BURNSVILLE...LE SUEUR...FARIBAULT...
RED WING...AMERY...BALSAM LAKE...RICE LAKE...BARRON...LADYSMITH...
HUDSON...NEW RICHMOND...RIVER FALLS...PRESCOTT...MENOMONIE...
BOYCEVILLE...DURAND...PEPIN...CHIPPEWA FALLS...BLOOMER...
EAU CLAIRE...ALTOONA
351 PM CST MON DEC 21 2009
...WINTER STORM WATCH IN EFFECT FROM WEDNESDAY EVENING THROUGH
FRIDAY AFTERNOON...
THE NATIONAL WEATHER SERVICE IN TWIN CITIES/CHANHASSEN HAS ISSUED
A WINTER STORM WATCH...WHICH IS IN EFFECT FROM WEDNESDAY EVENING
THROUGH FRIDAY AFTERNOON.
* TIMING...SEVERAL PERIODS OF SNOW ARE EXPECTED FROM WEDNESDAY
EVENING THROUGH FRIDAY AFTERNOON.
* ACCUMULATIONS...SIGNIFICANT AMOUNTS OF SNOW WILL OCCUR OVER THE
WATCH AREA...WITH PERIODS OF HEAVY SNOW POSSIBLE AS THE STORM
INTENSIFIES THURSDAY AND FRIDAY.
* SURFACE VISIBILITY WILL BE SIGNIFICANTLY REDUCED AS WIND
INCREASE TO 20 TO 30 MPH FROM THE EAST ON WEDNESDAY...BECOMING
MORE NORTHEAST...THEN NORTH ON FRIDAY.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
A WINTER STORM WATCH MEANS THERE IS A POTENTIAL FOR SIGNIFICANT
SNOW...SLEET...OR ICE ACCUMULATIONS THAT MAY IMPACT TRAVEL.
CONTINUE TO MONITOR THE LATEST FORECASTS.
&&
$$
JLT/JPR
.JPG)
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