Dec 11-13 MW/Lakes/OV Snow Event? Part III

[baroclinic_instability]

I will settle on a track maybe 20-30 miles south along the Iowa/MN/WI/ILL border. SREF/NAM are in good agreement with that and it matches current trends. Either way, this storm will be fun to watch for everyone.

[A-L-E-K]

I will settle on a track maybe 20-30 miles south along the Iowa/MN/WI/ILL border. SREF/NAM are in good agreement with that and it matches current trends. Either way, this storm will be fun to watch for everyone.

There seems to be pretty good agreement here.

[wisconsinwx]

Maybe it's just me, but I continue to see the GGEM shafting far southeast Wisconsin. If that's true, we'll probably get less snow than those in the Ohio Valley. That better be a mistake. It seems like we get a few hours of backend snows, while everyone N, W, E, and many S get a nice fulfilling snow.

[weatherbo]

reguardless, N IN looks to get hit

[A-L-E-K]

reguardless, N IN looks to get hit

I'll take my 4.25 and wow, major inland penetration there.

[ArmyGreens]

All I know is that having winter storm advisories to my nw and e are driving me nuts! I hope this pans out in some form or another for Ohio.

[JoMo]

That's a big dry slot there

[weatherbo]

I'll take my 4.25 and wow, major inland penetration there.

Inland band looks a bit oddly placed to me, but that could be the weenie inme talking, but seems a tad too far west for what I have seen in the past.

[MadTown]

towel is thrown in here

[A-L-E-K]

That's a big dry slot there

pretty much going to kill my chances at meaningful snow.

[LizardMafia]

I made a map earlier for my blog.

Boooooo!

[mnchaser]

18z NAM looks prime, hour 24-36 is a down right blizzard here if that verifies. Looks like we get briefly dry slotted as the low passes 150-200 or so miles to my south tonight, before things really start cranking around the morning hours. It's basically a bulls eye for Mankato and points northeast on this run.

Blizzard Warning issued here as expected.

THE NATIONAL WEATHER SERVICE IN TWIN CITIES/CHANHASSEN HAS ISSUED

A BLIZZARD WARNING...WHICH IS IN EFFECT FROM MIDNIGHT TONIGHT TO

MIDNIGHT CST SATURDAY NIGHT. THE WINTER STORM WARNING HAS BEEN

CANCELLED AND REPLACED WITH A BLIZZARD WARNING.

* TIMING...SIGNIFICANT SNOW BEGINNING LATE THIS EVENING AND

LASTING INTO SATURDAY EVENING.

* MAIN IMPACT...6 TO 10 INCHES OF SNOW IS LIKELY ACROSS SOUTH

CENTRAL MINNESOTA.

* OTHER IMPACTS...A PERIOD OF LIGHT FREEZING RAIN...SLEET...AND

SNOW IS EXPECTED TONIGHT INTO EARLY SATURDAY...WITH ICE

ACCUMULATIONS BELOW ONE TENTH OF AN INCH. STRONG WINDS WILL

DEVELOP ON SATURDAY...AND WILL RESULT IN BLIZZARD

CONDITIONS...ESPECIALLY IN OPEN COUNTRY. WIND CHILLS WILL

PLUMMET TO AROUND 30 BELOW ON SATURDAY NIGHT.

[baroclinic_instability]

towel is thrown in here

Don't know why you are throwing in the towel, still going to get some meaningful fluffy deformation zone snow on the back end with some good wind.

[A-L-E-K]

If the NAM is right, Skilling and I bust by 5 inches

[mississaugasnow]

well pittsburgh has issued a winter storm watch. this entire setup is baffling to me.

...WINTER STORM WATCH IN EFFECT FROM SUNDAY AFTERNOON THROUGHMONDAY EVENING...THE NATIONAL WEATHER SERVICE IN PITTSBURGH HAS ISSUED A WINTERSTORM WATCH...WHICH IS IN EFFECT FROM SUNDAY AFTERNOON THROUGHMONDAY EVENING.A STRONG LOW PRESSURE SYSTEM WILL SPREAD A WINTRY MIX ACROSS THEWATCH AREA SATURDAY NIGHT INTO SUNDAY. PRECIPITATION WILL CHANGETO ALL SNOW SUNDAY AFTERNOON. WIDESPREAD SNOW SHOWERS WILL DEVELOPSUNDAY NIGHT AND MONDAY ALONG WITH STRONG WINDS. THIS WILL BRINGBLOWING AND DRIFTING SNOW AS WELL AS QUITE COLD WIND CHILLS.

[The_Global_Warmer]

nam is quite a bit further SW at the Upper levels.

[janetjanet998]

rather large difference in the 18z NAM at 12z sunday

12z

18z

[A-L-E-K]

rather large difference in the NAM at 12z sunday

Where have you been?

consolation prize

[jhamps10]

rather large difference in the NAM at 12z sunday

yeah... very large difference... enough to make the Bears game look interesting should the NAM verify...

[A-L-E-K]

There she blows. Looks right on track.

[jbcmh81]

well pittsburgh has issued a winter storm watch. this entire setup is baffling to me.

...WINTER STORM WATCH IN EFFECT FROM SUNDAY AFTERNOON THROUGHMONDAY EVENING...THE NATIONAL WEATHER SERVICE IN PITTSBURGH HAS ISSUED A WINTERSTORM WATCH...WHICH IS IN EFFECT FROM SUNDAY AFTERNOON THROUGHMONDAY EVENING.A STRONG LOW PRESSURE SYSTEM WILL SPREAD A WINTRY MIX ACROSS THEWATCH AREA SATURDAY NIGHT INTO SUNDAY. PRECIPITATION WILL CHANGETO ALL SNOW SUNDAY AFTERNOON. WIDESPREAD SNOW SHOWERS WILL DEVELOPSUNDAY NIGHT AND MONDAY ALONG WITH STRONG WINDS. THIS WILL BRINGBLOWING AND DRIFTING SNOW AS WELL AS QUITE COLD WIND CHILLS.

Must be from LES?

[ValpoVike]

Northern Indiana WSW:

URGENT - WINTER WEATHER MESSAGE

NATIONAL WEATHER SERVICE NORTHERN INDIANA

331 PM EST FRI DEC 10 2010

...WINTER STORM WATCH IN EFFECT FOR LAKE EFFECT SNOW SHOWERS...BLOWING

AND DRIFTING SNOW SUNDAY AFTERNOON THROUGH MONDAY MORNING...

.LOW PRESSURE WILL DEVELOP AND MOVE ACROSS THE GREAT LAKES THIS

WEEKEND. WHILE DETAILS ON THE EXACT TRACK REMAIN

QUESTIONABLE...LAKE EFFECT SNOW SHOWERS...ENHANCED BY THE AREA OF

LOW PRESSURE...ARE EXPECTED TO DEVELOP ACROSS THE WATCH AREA BY

SUNDAY AFTERNOON AND CONTINUE INTO AT LEAST MONDAY. IT REMAINS TOO

EARLY TO DETERMINE EXACTLY WHERE THE HEAVIEST SNOW MAY FALL.

HOWEVER...THE POTENTIAL EXISTS FOR 6 TO 10 INCHES OF SNOW ACROSS

PORTIONS OF THE WATCH AREA BY MONDAY MORNING...WITH LOCALLY HIGHER

AMOUNTS. IN ADDITION...STRONG WINDS WILL CAUSE WIDESPREAD BLOWING

AND DRIFTING SNOW...CAUSING NEAR WHITEOUT CONDITIONS AT

TIMES...ESPECIALLY IN OUTLYING AREAS.

[MadTown]

FXUS63 KMKX 102024

AFDMKX

AREA FORECAST DISCUSSION

NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI

224 PM CST FRI DEC 10 2010

.TONIGHT THROUGH SATURDAY NIGHT...FORECAST CONFIDENCE MEDIUM.

FORECAST CHALLENGE REMAINS EXTREMELY HIGH FOR THE IMPENDING WINTER

STORM MOVING THROUGH THE REGION LATER TONIGHT THROUGH SATURDAY

NIGHT. THE 12Z NUMERICAL MODEL GUIDANCE DID NOT COME INTO A

REASONABLY TIGHT CONSENSUS...AND THIS IS PRETTY UNUSUAL GIVEN THE

SHORT WINDOW UNTIL THE ONSET OF THE PRECIP. FOCUS OFTEN IS ON THE

INCREMENTAL SFC LOW POSITIONS FROM THE VARIOUS MODELS. THIS IS

USED AS A ROUGH GUIDE AS TO WHERE THE HEAVIEST SNOW WILL FALL. A

TRACK ACROSS CHICAGO USUALLY MEANS ALL BUT OUR SOUTHERN 1/3 OF THE

CWA WILL SEE APPRECIABLE SNOW ACCUMULATIONS. THREE TO FOUR DAYS

AGO...THE MODELS HAD A STORM MOVING THROUGH THE OHIO VALLEY...

ESSENTIALLY MISSING US. THEN 36 HOURS AGO MANY OF THE MODELS

SHIFTED...RATHER JUMPED...FAR NORTH...TAKING THE LOW ACROSS

CENTRAL AND SOUTHERN WISCONSIN. THAT MEANT MORE OF WET/MIXY WINTER

EVENT FOR US. THE SHIFT NORTH ISN/T UNUSUAL...THE DEGREE OF THE

JUMP WAS.

THE MODELS APPEAR TO BE SHIFTING FARTHER SOUTH NOW. THE UKMET AND

THE CANADIAN MODELS ALWAYS HAD A SOLUTION SOUTH OF WISCONSIN..

ACTUALLY SOUTH OF CHICAGO. THE 12Z NAM AND THE 00Z ECMWF HAVE A

LOW MOVING ACROSS THE MIDDLE OF OUR CWA...NOT FAVORABLE FOR SNOW.

THE 12Z GFS SHIFTED SOUTH...MOVING IT ALONG THE WI/IL BORDER WITH

THE ENSEMBLE GFS SHOWING A MAJORITY OF MEMBERS OVER CHICAGO.

THAT/S TROUBLESOME AND MEANS A COLDER AND SNOWIER SOLUTION THAN

WHAT WE HAD. THE 12Z ECMWF CAME IN AND IS ACTUALLY JUST SOUTH OF

THE WI/IL BORDER NOW. MORE TROUBLE. LOOKING AT THE THERMAL PROFILE

AND THE AMOUNT OF QPF EXPECTED...THAT COULD BRING WARNING SNOW TO

MUCH OF THE CURRENT WINTER STORM WATCH AREA.

GIVEN THE VARIED SOLUTIONS OUT THERE...WILL ISSUE A WINTER STORM

WARNING FOR OUR TWO NRN ROW OF COUNTIES...MINUS OZAUKEE AND

WASHINGTON. KEEP THE WATCH AND ACTUALLY EXPAND IT A BIT. NEED TO

SEE MORE CONSENSUS ON A SOUTHERN SOLUTION BEFORE THERE IS ENOUGH

CONFIDENCE EXPAND THE WARNING. IN FACT...THE NAM/S NORTHERN

SOLUTION MAY END UP BEING RIGHT AND THIS WOULD MAKE THIS FORECAST

A BIG GOOSE EGG. WE MAY SEE WINTER STORM WARNING CONDITIONS ON

SUNDAY DUE TO THE EXTREME WIND AND BLOWING SNOW EXPECTED...THUS

THE EXPANSION OF THE WATCH TO THE WI/IL BORDER.

THE SOUTHERN SHIFT MAKES SENSE GIVEN THE BEHAVIOR OF THE UPPER

LEVEL FEATURES. THE 500 AND 700MB LOWS ARE ALL VERY

SOUTH...CENTRAL ILLINOIS IN SOME CASES...OF THE SFC AND H8 LOW

CENTERS AND THIS IS RATHER INVERTED FROM TYPICAL SYNOPTIC

ORIENTATION. SO...TO SEE THE LOWER LEVELS PULLED/FOCUSED CLOSER TO

THE UPPER LEVELS...MAKES MORE SENSE.

incredible...guess the towel is back in the game

[janetjanet998]

Here is the 12z vs 18 nam 24 hr precip after 00z sunday through 00z monday all would be snow over MI and IL

notice the heaveist precip is more south in MI on the 18z

12z

18z

[Harry]

The euro ensembles did slide a bit south. Per them the dryslot never makes it to downtown Chicago and or north of i80.

[mississaugasnow]

from the sounds it, they are thinking more system. Without any support since im still a novice when it comes to models I would have to say that this will likely be downgraded to winter weather advisory for a couple inches of snow with strong winds causing visibility issues? and the counties that have the chance to get in on the LES will likely be upgraded to LES advisories/warnings?

Must be from LES?

[A-L-E-K]

The euro ensembles did slide a bit south. Per them the dryslot never makes it to downtown Chicago and or north of i80.

I appreciate the pep talk.

[Moneyman]

...WINTER STORM WARNING IN EFFECT FROM NOON SATURDAY TO 6 PM CST

SUNDAY...

THE NATIONAL WEATHER SERVICE IN MILWAUKEE/SULLIVAN HAS ISSUED A

WINTER STORM WARNING FOR HEAVY SNOW AND BLOWING SNOW...WHICH IS

IN EFFECT FROM NOON SATURDAY TO 6PM CST SUNDAY. THIS IS AN UPGRADE

TO THE WINTER STORM WATCH.

* TIMING...A MIXTURE OF SNOW...SLEET AND FREEZING RAIN WILL

DEVELOP SATURDAY TOWARD LATE MORNING. THE MIXTURE WILL THEN

CHANGE TO SNOW DURING THE LATE AFTERNOON AND CONTINUE SATURDAY

NIGHT. THE SNOW WILL BE HEAVY AT TIMES. BLOWING AND DRIFTING

SNOW IS EXPECTED SATURDAY NIGHT AND SUNDAY AS THE WINDS INCREASE.

* SNOW ACCUMULATIONS...ABOUT 12 INCHES OF SNOW IS LIKELY IN FOND

DU LAC AND WESTERN SHEBOYGAN COUNTIES...WITH 7 TO 10 INCHES

ELSEWHERE.

[Paweatherguy1]

Must be from LES?

It is rare to get a watch for LES here...actually never happens. I think they are banking on a quick 2-4 burst after our changeover early sunday afternoon, then additional LES and bitter cold and high winds. If you add that all together we could get 4-8 inches, all be it over a 36 to 48 hour period.

[ValpoVike]

from the sounds it, they are thinking more system. Without any support since im still a novice when it comes to models I would have to say that this will likely be downgraded to winter weather advisory for a couple inches of snow with strong winds causing visibility issues? and the counties that have the chance to get in on the LES will likely be upgraded to LES advisories/warnings?

I believe that what normally would be a LES warning will turn into a WS warning in the presence of other factors such as wind, blowing/drifting, ice, etc.