December 21-22nd Winter Storm Part 3

[snowstormcanuck]

I wasn't talking about 850 mb temps. I was talking abut surface temps.

 

You were responding to my question about temps aloft.

 

Get some sleep.

[Thundersnow12]

GFS and Euro are both decent hits for northwest IL.  If the southeast trend continues tomorrow we could easily be bumped out of it, so definitely nothing to get too excited about yet.  If models looked like this with the 00z suite tomorrow night I'd start to become pretty optimistic. 

 

I'd call both significant > decent. The Euro's defo band depiction at 12z Sun is impressive to say the least.

[Chicago Storm]

Outside of the system position/precip/thermals...The other sig difference in guidance over the past 24hrs is for the ejecting wave not to shear out, and instead stay fairly sig as it ejects northeast.

[Harry]

The question is when does it stop.

 

Rip city defo band at 60hr.

 

Good question? Wondering if it goes back to what it originally had ( for days ) before the sudden shift to the nw? QPF and all is almost back to what it was.. That high to the north also keeps coming in stronger as well. Really don't wanna make any guesses till the models have sampled this thing.

[Thundersnow12]

Outside of the system position/precip/thermals...The other sig difference in guidance over the past 24hrs is for the ejecting wave not to shear out, and instead stay fairly sig as it ejects northeast.

 

This.

 

If anyone needs a visual go compare the last 4 runs of the GFS looking at H5 vorticity valid 6z Sunday.

[Thundersnow12]

Good question? Wondering if it goes back to what it originally had ( for days ) before the sudden shift to the nw? QPF and all is almost back to what it was.. That high to the north also keeps coming in stronger as well. Really don't wanna make any guesses till the models have sampled this thing.

 

Yeah I'm just not sure. I think it would be amazing if it did happen.

[cyclone77]

Last night at this time the new Euro showed the heaviest snow from Des Moines through Waterloo.  Tonight it's centered around the QC.  Chances are this time tomorrow night it will be significantly different again.  Like I said a few days ago this system is gonna mess with us down to the end.  It's nice to see the deformation band being shown as very robust on recent runs.

[cyclone77]

With recent trends of the ejecting wave holding off on shearing off I'd expect the NAM to finally get a clue and spit out some big numbers with tomorrow's 12z. 

[Geos]

Last night at this time the new Euro showed the heaviest snow from Des Moines through Waterloo.  Tonight it's centered around the QC.  Chances are this time tomorrow night it will be significantly different again.  Like I said a few days ago this system is gonna mess with us down to the end.  It's nice to see the deformation band being shown as very robust on recent runs.

 

I don't know we're within 48 hours now. I wouldn't expect anything over 50 miles shift now.

[hm8]

WPC liking a Euro/Ukie Blend

...DEVELOPING CLOSED LOW OVER THE SOUTHWEST/NORTHERN

MEXICO...EJECTING OUT TOWARD THE SOUTHERN PLAINS AND SHEARING

NORTHEAST ACROSS THE MIDWEST...

...DEVELOPING SURFACE LOW OVER THE LOWER/MIDDLE MISSISSIPPI VALLEY

AND OHIO VALLEY...

PREFERENCE: 00Z UKMET/00Z ECMWF BLEND

CONFIDENCE: BELOW AVERAGE

LATEST GOES-RGB SAT IMAGERY SHOWS A VERY WELL-DEFINED UPPER LOW

AND ASSOCD PV ANOMALY DIGGING SOUTH THROUGH SRN CA AND THE

ADJACENT OFFSHORE WATERS. THIS ENERGY WILL SWING SEWD ACROSS NRN

MEXICO BEFORE EJECTING EAST OUT INTO THE SRN PLAINS AND LOWER MS

VALLEY FRI THROUGH SAT. THE UPPER LOW/ENERGY IS THEN EXPECTED TO

SHEAR NEWD ACROSS THE MIDWEST THROUGH SUN OUT AHEAD OF ENCROACHING

NRN STREAM SHORTWAVE ENERGY ADVANCING DOWN ACROSS THE NRN PLAINS

AND UPR MIDWEST. THE SRN STREAM UPPER LOW/ENERGY WILL INTERACT

WITH A STRONG BAROCLINIC ZONE DRAPED FROM THE SRN PLAINS NEWD UP

INTO THE OH VLY AND SHOULD FOSTER A SIGNIFICANT WAVE OF LOW

PRESSURE...DEVELOPING INITIALLY OVER NERN TX ON SAT AND THEN

LIFTING PROGRESSIVELY NEWD UP THROUGH THE OH VLY/LWR GRT LAKES AND

NEW ENGLAND THROUGH SUN.

THE LATEST MODELS SHOW REASONABLY GOOD MASS FIELD AGREEMENT UNTIL

ABOUT 36 HOURS...WHEN THE 12Z ECMWF HAD SUGGESTED THAT THE SRN

STREAM ENERGY MAY TEND TO REMAIN A BIT STRONGER/SHARPER IN LIFTING

NEWD OUT OF THE SRN PLAINS TWD THE MIDWEST. THE GLOBAL MODEL

CONSENSUS HAS BEEN FOR THE ENERGY TO BEGIN DAMPENING OUT RATHER

QUICKLY AS IT ENCOUNTERS INCREASINGLY CONFLUENT FLOW ALOFT

DOWNSTREAM. THE STRONGER 12Z ECMWF ALLOWED FOR STRONGER SURFACE

LOW PRESSURE TO EVOLVE OVER THE LWR MS VLY/OH VLY AND INTO THE LWR

GRT LAKES REGION...WHILE ALSO TENDING TO TRACK LEFT OF THE GLOBAL

MODEL CONSENSUS.

THE 00Z ECMWF HAS TRENDED A TAD WEAKER THOUGH ALOFT WITH THE

ENERGY...AND IS A LITTLE WEAKER AND MORE SUPPRESSED WITH ITS LOW

TRACK COMPARED TO PREV MDL CYCLES. HOWEVER...THE 00Z GFS...WHILE

APPEARING REASONABLE ALOFT...BECOMES QUITE SLOW AND ILL-DEFINED

WITH ITS EJECTING SURFACE LOW CENTER. ITS BAROCLINIC ZONE ACROSS

THE OH VLY AND NORTHEAST IS ALSO A BIT MORE SUPPRESSED. THE 00Z

GEM GLOBAL AND 00Z UKMET DO NOT SUPPORT THE MASS FIELD DETAILS OF

THE GFS...AND ARE FASTER AND A LITTLE FARTHER NORTH WITH THE LOW

TRACK...AND CLUSTER RATHER WELL WITH THE 00Z ECMWF. THE 00Z NAM IS

NOW THE FARTHEST NORTH AND MOST PROGRESSIVE SOLN SURFACE AND

ALOFT. THE LATEST GEFS MEAN AND ECENS MEAN DO NOT SUPPORT THE GFS

AND LEAN STRONGER SUPPORT FOR THE NON-NCEP CLUSTER. WHILE

CONFIDENCE REMAINS LOW...THE STRONGER CLUSTERING AS PER THE 00Z

UKMET AND 00Z ECMWF...MAKE A BLEND OF THESE SOLNS REASONABLE ATTM.

[nwburbschaser]

I don't know we're within 48 hours now. I wouldn't expect anything over 50 miles shift now.

50 miles is still a decent sized shift though.

[cyclone77]

50 miles is still a decent sized shift though.

 

Definitely.  We're not dealing with the traditional wide swath of snow we see with most Dec storms.  Even though by then it's a bit premature, I'll make my first calls for here and the QC after the 12z suite rolls in.

 

EDIT:  fixed my asinine grammerabilitiezz

[Geos]

Definitely.  We're not dealing with the traditional wide swath of snow we see with most Dec storms.  Even though by then it's a bit premature, I'll make my first calls for here and the QC after the 12z suite rolls in.

 

EDIT:  fixed my asinine grammerabilitiezz

 

I can see your point given that then. It is pretty narrow.

[Stebo]

Latest from WPC:

 

[alexanderhall]

From Al Marinaro on Twitter:

 

 

Thought you guys would appreciate. 

 

Lightning data from: 

http://www.lightningstorm.com/explorer.html

[weatherbo]

man you guys sleep late. where is everybody, we got a storm to track!

pending call: 5.2" thru 7 pm Sunday

[gosaints]

Ya can't believe we are not breaking down the 6z rgem

[Harry]

man you guys sleep late. where is everybody, we got a storm to track!

pending call: 5.2" thru 7 pm Sunday

 

Some ( cough cough) still have not gone to bed yet!

[Whitelakeroy]

man you guys sleep late. where is everybody, we got a storm to track!

pending call: 5.2" thru 7 pm Sunday

It is dead this morning.  Everyone must be getting some sleep before this all gets going.  Have to say the 6Z track is HORRID for MBY ... almost right over DTW.  Unfortunately I am 75% percent confident it is right.  Right now I would be booking a trip to your area if family wasn't coming in town.  I think Jonger is going to nail it with his Cadillac call!!

[Baum]

Ya not even an early morning update from Aleking. Going to touch and go in Chicagoland

[kevlon62]

Saturday night point bumped up from 3-5" to 3-7".

[A-L-E-K]

Ya not even an early morning update from Aleking. Going to touch and go in Chicagoland

 

 

non event for MBY

 

next

 

EDIT: for those who missed my final call

 

1.2 (i think that's what it was) total QPF: little more than 1/2 of that plain rain, little more than half IP (bad call...should be more of a wet rain/snow mix), and a little under an inch SN.

 

SREF plumes continue to trend down for ORD, now under 1"

[buckeye]

Not difficult to imagine all of this shifting south, the combination of snow already on ground and far-south origins of eventual low pressure combined with chilly high already in place are all danger signs for a warm solution. The models already have the low pressure fairly far south but the thickness pattern oddly north, so what could change first is the orientation of thickness to low pressure. This would all argue for the freezing rain or ice pellets to be located largely south of where they are currently expected and snow to fall where freezing rain and ice pellets are expected (as well as where snow is now expected). I also have some doubts about 60s moving into IN and OH although that could still happen on a limited basis if the zones shift south. We shall see, eventually.

 

The above would imply mostly snow in Toronto with some mixing to ice pellets, a broad mix in Niagara and western NY and also mostly snow in Detroit with some mixing, freezing rain across northern Ohio and Indiana into central IL, all or mostly snow in Chicago.  Probably not what people are going to forecast at least until Saturday, but that's how I suspect it might work out.

 

I'm thinking this part of your forecast might be in jeopardy.   Low to mid 50's this morning across southern half of OH....and the peak of the warm surge is still 24 hours away.  Heavy steady rain could save it from happening I suppose.

[Chicago WX]

First WAG

 

LAF: 2.55" precip, 0.0" freezing or frozen

Alek: 1.00" precip, 0.05" freezing, 0.5" frozen

BowMe: 1.10" precip, 0.10" freezing, 7.5" frozen

cyclone: 1.00" precip, 0.30" freezing, 5.0" frozen

Geos: 1.05" precip, 0.20" freezing, 6.0" frozen

IKK: 1.30" precip, 0.20" freezing, 0.2" frozen

[A-L-E-K]

new LOT, wagons west

 

[Chitown Storm]

Either everyone stayed up late analyzing the data, or everyone has lost interest. Ghost town this morning!

I see this as one of those classic storms where northern burbs of Chicago get pounded and southern portions see mostly liquid or minor ice. Whenever the freezing line is this close, I always get the short end if the deal.

[A-L-E-K]

Either everyone stayed up late analyzing the data, or everyone has lost interest. Ghost town this morning!

I see this as one of those classic storms where northern burbs of Chicago get pounded and southern portions see mostly liquid or minor ice. Whenever the freezing line is this close, I always get the short end if the deal.

 

LOT's map looks good. Models always under play the dry on the southern edge of the defo band as well...not that it isn't already being hinted at pretty hard.

[weatherbo]

It is dead this morning. Everyone must be getting some sleep before this all gets going. Have to say the 6Z track is HORRID for MBY ... almost right over DTW. Unfortunately I am 75% percent confident it is right. Right now I would be booking a trip to your area if family wasn't coming in town. I think Jonger is going to nail it with his Cadillac call!!

I'm liking the trends and where I sit as of now but know enough to never get too comfortable or cocky.

[blizzardof96]

Model consensus looks really bad for the GTA. 4km NAM has widespread amounts of 0.5-1.5" of ice at pearson with a thin PL glaze beforehand. Euro has about 0.9-1.3" of ice. RGEM has 15-25mm along the 401, 10-15mm downtown and 20-35mm north of the 401 and over hamilton/burlington/guelph/milton areas. If model amounts verify, many parts of the GTA are going to be looking at major power outages.

[A-L-E-K]

NAM looks warm.north