Nov 12-14th MW/Lakes Snow Event

[Chicago Storm]

Take 2.

[cromartie]

Congrats MSP

[Powerball]

Congrats MSP

It's a lock for the NW suburbs.

It's still too close of a call for Minneapolis proper and especially S/E, unless we can get a pretty good CCB to setup overhead, similar to what Amarillo had earlier today.

[Thundersnow12]

12z sounding from OAX this morning, showing the environment were dealing with. about -2 degrees at 850mb. also, quite amazing what happened in AMA this morning.

[oldlogin]

Looks like HPC is getting down to detail---Where would the red dot be ??? Hayward ?? Eau Clarie?

[Powerball]

Actually, after further review of Amarillo, they picked up about .60" of pure snow today, so I suspect half of that (2-4") actually accumulated with respect to its convective nature, granted it would be more impressive if this happened at a lower elevation than 3,500 feet.

I did notice they were under a winter weather advisory for some time.

[Thundersnow12]

nice looking WV loop of things getting going.

http://weather.cod.edu/loops/US-WV24.loop.html

[Thundersnow12]

off the 15z HRRR, could be quite a show overnight in MN..

[oldlogin]

The ensembles indicate that the Low deepens as it moves North.

[Thundersnow12]

The ensembles indicate that the Low deepens as it moves North.

probably the most clustered track we'll see all winter! haha

[oldlogin]

probably the most clustered track we'll see all winter! haha

Yeah, I too was surprised at the lack of deviation. Were not used to that from the models--

[Cyrys]

Point forecast from the NWS is showing 4-6 inches here in Chaska for the storm. TV met at lunch from WCCO called for 4-8 across the MSP metro. It'll be my favorite type of snow storm, a heavy wet snow that sticks to all the branchs, and the roads will be too warm for any significant accumulation.

[mnchaser]

It's been snowing in Albert Lea in Southeastern MN(60 miles south of me) near the Iowa border for a few hours now, Their temp is down to 32, Seems like the rain cooled it down enough to change over to snow, but as the low lifts north I expect them to switch back to a mix this evening..Looking at this makes one think the changeover process might be easier for my area..It's going to come awfully close to a hit or miss for me..

[Powerball]

It's been snowing in Albert Lea in Southeastern MN(60 miles south of me) near the Iowa border for a few hours now, Their temp is down to 32, Seems like the rain cooled it down enough to change over to snow, but as the low lifts north I expect them to switch back to a mix this evening..Looking at this makes one think the changeover process might be easier for my area..It's going to come awfully close to a hit or miss for me..

Nice, it makes sense given the pocket of sub-zero 925mb temps overhead right now...

But of course it will be harder for them to wet bulb snow later on as the profiles warm (since the air is saturated).

[Powerball]

Link

000

FXUS63 KMPX 121759

AFDMPX

AREA FORECAST DISCUSSION

NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN

1159 AM CST FRI NOV 12 2010

.AVIATION.../18Z TAF ISSUANCE/

MAIN CONCERN THIS TAF PERIOD IS THE POTENTIAL FOR A SIGNIFICANT

ACCUMULATING SNOW LATE TONIGHT INTO SATURDAY. BAND OF MID LEVEL

FGEN HAS FORCED A PERSISTENT BAND OF SHOWERS FROM CENTRAL IA NE TO

NEAR EAU. EXPECT THIS TO BASICALLY REMAIN STATIONARY THROUGH

00Z...WITH ALL BUT EAU REMAINING DRY UNTIL CLOSER TO 06Z WHEN A

SIGNIFICANT SHORTWAVE BEGINS HEADING NORTH OUT OF TEXAS. OUTSIDE

OF THE PRECIP BAND...EXPECT CIGS TO REMAIN VFR UNTIL CLOSER TO

06Z...WHEN ALL MODELS IN GOOD AGREEMENT ON QUICKLY DROPPING CIGS

AS DEEP FORCING/MOISTURE APPROACHES. BIGGEST QUESTION MARK WITH

THIS PERIOD IS WHERE WILL THE RAIN/SNOW LINE SETUP SAT

MORNING...AND THEN WHEN DOES THE TRANSITION OCCUR. BLENDING THE

NAM/GFS...IT LOOKS LIKE THE RA/SN LINE WILL SETUP NEAR AN

MKT/MSP/RNH LINE WITH SIGNIFICANT SNOW ACCUMULATIONS /6 TO 10+ IN/

LIKELY JUST TO THE WEST OF WHERE THIS SETS UP. STC LOOKS TO BE THE

MOST LIKELY TO SEE MOSTLY SNOW...WHILE THERE IS STILL A FAIR

AMOUNT OF UNCERTAINTY FOR MSP AND RNH. HIGH CONFIDENCE IN EAU

STAYING WITH -RA. AXN/RWF WILL BE SEEING SNOW AS WELL...BUT WILL

BE WEST OF THE HEAVIEST PRECIP WITH MAYBE AN INCH POSSIBLE AT AXN

AND 2 TO 4 IN RWF.

KMSP...MAIN ISSUE THIS TAF IS WITH P-TYPE. HAVE MODERATE

CONFIDENCE IN THE P-TYPE...BUT MSP DOES LOOK TO BE VERY CLOSE TO

THE RA/SN LINE. THE TOTAL SNOW MSP RECEIVES WILL BE HIGHLY

DEPENDENT ON WHEN/IF A COMPLETE TRANSITION TO SNOW OCCURS.

OBSERVATIONS FROM ALBERT LEA AND ROCHESTER THIS AFTERNOON WOULD

SUPPORT THE IDEA OF SEEING AN EARLIER TRANSITION /CLOSE TO 09Z/.

BOTH AEL AND RST HAVE BEEN IN PERSISTENT RAIN ALL MORNING...AND

WITHIN THE LAST COUPLE OF HOURS...THEY HAVE COOLED ENOUGH TO

TRANSITION P-TYPE OVER TO -SN. CONFIDENCE IS HIGH IN ACCUMULATIONS

COMING IN IN THE 3 TO 6 INCH RANGE BY SUNDAY MORNING...BUT THE

POTENTIAL DOES EXIST TO SEE UPWARDS OF 10 INCHES WITH THIS STORM.

DESPITE THE WARM SFC CONDITIONS...SNOWFALL RATES SHOULD BE HIGH

ENOUGH FOR THE SNOW TO ACCUMULATE AND SOME FOR OF SNOW REMOVAL

WILL BE NEEDED TO KEEP THE THINGS FLOWING. EXPECT HEAVIEST PRECIP

TO FALL IN THE 10Z TO 20Z TIME RANGE.

[mnweather]

Might be rain for me near Lake Superior. Inland locations should do well.

[Stebo]

Lets build that snow cover

[prinsburg_wx]

It's been snowing in Albert Lea in Southeastern MN(60 miles south of me) near the Iowa border for a few hours now, Their temp is down to 32, Seems like the rain cooled it down enough to change over to snow, but as the low lifts north I expect them to switch back to a mix this evening..Looking at this makes one think the changeover process might be easier for my area..It's going to come awfully close to a hit or miss for me..

updated HPC snow probs and Mankato hits the jackpot...im on the western side of this thing so hoping to get a few inches.

[Cyrys]

Winter storm warnings up now. My point forecast has been upped from 4-6 to 5-11.

[OceanStWx]

Glad to be in the warm sector on this one. Totally unprepared for scraping my windshield and driving in for the early shift on untreated roads.

[csnavywx]

MSP is going to get close, but I think they switch to snow completely and stay there this evening fairly early (8-10 pm). The best snowfall rates aren't even until later tomorrow morning though. Could see a few places get 1-2"/hr, MSP included.

Lack of a real warm layer aloft and strong dynamic cooling should do the trick. I would expect there to be a very sharp cutoff to the snow totals on the east side though. 6" in one spot and next to none 10 miles east type of deal.

[Powerball]

12z GGEM says bust from Minneapolis and S/E. In fact, Minneapolis never transitions completely over to snow per the GGEM (except at the very end during the wrap around).

[OceanStWx]

MSP is going to get close, but I think they switch to snow completely and stay there this evening fairly early (8-10 pm). The best snowfall rates aren't even until later tomorrow morning though. Could see a few places get 1-2"/hr, MSP included.

Lack of a real warm layer aloft and strong dynamic cooling should do the trick. I would expect there to be a very sharp cutoff to the snow totals on the east side though. 6" in one spot and next to none 10 miles east type of deal.

From what I've looked at, as the low strengthens upper level temps really crash southeast, eliminating that melting threat. Plus we have the warm air bottled up down in our CWA. It's 67 in Macomb, IL and 41 in Independence, IA.

[Powerball]

18z run of the GGEM shows the same thing.

[Powerball]

In fact, even the 12z NAM had Minneapolis mixing/transitioning to rain for a good while.

The CCB will definitely make or break this event for the immediate metro area.

[Thundersnow12]

From what I've looked at, as the low strengthens upper level temps really crash southeast, eliminating that melting threat. Plus we have the warm air bottled up down in our CWA. It's 67 in Macomb, IL and 41 in Independence, IA.

ya pretty sharp warm fronts at 850mb and 925mb as well. I think the big winners will be west of MPX. should be fun to watch our first winter system.

The only obs with snow at the moment that I saw were BIE and AUM and that was -SN both at 34/32

[wishforsnow]

Might be rain for me near Lake Superior. Inland locations should do well.

Rain for I live too. I only live 8 miles from Lake Superior. We are also on the warmer side of the storm. The early storms always go west due to the big lake being warmer this time of year. That is what the local meteorologist says. I can't wait until we get that arctic air to crank up the lake effect.

[Chicago Storm]

0748 PM SNOW OMAHA 41.26N 96.01W

11/12/2010 E1.5 INCH DOUGLAS NE BROADCAST MEDIA

ESTIMATED NEAR MIDTOWN.

[Powerball]

CCB is setting up right over Omaha, so now they're under a winter weather advisory for 2-4"

Granted, it's quite plausible those numbers are still too low yet giving the healthy/maturing deformation axis stretching back into Kansas and the fact that it's nighttime.

Interestingly enough all the soundings there are ABOVE freezing right up to 800mb, so it's a testament of how intense the lift with this storm is.

[Powerball]

Amazingly, within the hour Omaha has crashed from 925mb temps of 3 to 4C to 0 to -1C. As a result the boundary layer temperatures have also crashed below freezing (last hour freezing levels were at 4,000 to 5,000 feet).

850mb temperatures are also slowly but steadily falling (from 1C last hour to -1C in Omaha).