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

[The_Global_Warmer]

I'm willing to bet there is a SLP up north to based on the elongated look to the pressure fields.

at 84 hours the ensemble mean has one LP in S. IL.

That is not the same.

[The_Global_Warmer]

What a strung out mess.

[prinsburg_wx]

18z NAM (I'll myself here) Looks like it wants to have a more dominant northern 850 as well, real good hit for Southern Minn / Northern Iowa

too bad it's the NAM at this range

[JoMo]

18z NAM (I'll myself here) Looks like it wants to have a more dominant northern 850 as well, real good hit for Southern Minn / Northern Iowa

Yep, was just looking at that. Entire system looks like poop though.

@ 84 hours Really elongated surface pressure... broad 925/850 MB Closed over IN/IL, Open 700, Open 500.

Snow depth through all 84 hours on the NAM

[A-L-E-K]

too bad it's the NAM at this range

The NAM and its suckiness are well documented, but i think it's fair game to discuss with such rag tag consensus across the board. FWIW it's not the only model to show good snows up north, even the southern 12z GFS run had nice snows up there.

[weatherbo]

From IWX this afternoon, the extended forecast looks very snowy here in N Indiana!

ALTHOUGH A LOT OF UNCERTAINTY IN THEIR AFD.

[jbcmh81]

Congrats to everyone along and north of I-80. And yes, this is a weenie post, but it's basically what I've been expecting all along.

[Chicago Storm]

at 84 hours the ensemble mean has one LP in S. IL.

That is not the same.

I'm aware of that.

I was talking about the start, not where it goes after.

[TheWeatherPimp]

ILN's new zones are out and they maintain all snow wording here in Western Ohio

[A-L-E-K]

From IWX this afternoon, the extended forecast looks very snowy here in N Indiana!

ALTHOUGH A LOT OF UNCERTAINTY IN THEIR AFD.

They'd be lying if there wasn't.

[jbcmh81]

ILN's new zones are out and they maintain all snow wording here in Western Ohio

Same here in CMH... mostly snow. I will have to read the AFD, but obviously they aren't going with the Euro.

[L.B. LaForce]

[roardog]

The problem is this storm is still a few days away. It has time to end up in northern lower Michigan yet. I'd like to welcome back the NW trend for another winter.

[beavis1729]

The latest from Gil Sebenste at NIU:

The new European model is back to taking the low across northern Illinois

Saturday night after crossing Iowa, and then rapidly intensifying over

Michigan. The GFS takes it from Arkansas into Nashville, TN Saturday

night. IMO, both are wrong, and it's a symptom of the utter lack of data

where the system is as to why the models are disagreeing so wildly. And,

of course, they're flip-flopping like a fish out of water. Like I said

yesterday, all I know is that someone here or close by south-east of us

could get very heavy snow, and all of the Great Lakes states should see

high winds on Sunday as the system "bombs out" and pressures fall to 980

millibars, or ~28.90" of mercury. Not the monster storm we saw a month

ago, but with an Arctic high following this, the wind field could be

nearly as strong as with that system to the west of the low track on

Sunday. Temperatures in the lower or middle 30s on Saturday could crash

into the single digits on Sunday as the Arctic air dumps southward behind

the departing system. Wind chills should be well below zero by late Sunday

across the area, possibly approaching or reaching wind chill advisory

levels around -20 degrees. Stay tuned...the system comes onshore

tomorrow...I hope to know more then.

Next week...Arctic high pressure moves over us, and we get the coldest air

of the season. How cold? That -10 is an estimate. If we get an inch of

snow, we may only be 0 to -5. If we get a half foot or more of snow, we

could be -10 to -20 degrees by Tuesday morning. Either way, it's going to

be very cold, with wind chills of 0 to -20...and possibly colder...on

Monday and into Tuesday morning, before we start to slowly moderate in the

middle and latter portion of next week...and our next chance of

significant snow wouldn't be until next weekend.

So, I wish I could be more specific about this weekend, but this system is

so big and complex, and our available resolution of data in the eastern

Pacific is low compared to what we need (and the models need) to properly

analyze the situation. Either way, it's going to be a big system...for

somebody.

[Thundersnow12]

[weatherbo]

They'd be lying if there wasn't.

believe this still passes along the OH river between cinci and Indy and south of Toledo, putthing the heaviest snow CHI/west and MI stae line/north.

[csnavywx]

To me, the 12z Euro Ensembles are huge.

There's probably going to be an inverted trough over the central plains, given the pronounced lee-side trough that develops and the decent difference between the relatively mild air ahead of the warm front and the arctic air behind the cold front. This is something the Euro perhaps went overboard with for a couple of days, hence the north track. Now it shows more of a classical system with an inverted trough/weak low that opens into a trough as the southern low becomes dominant. These systems tend to cut towards their inverted troughs as they mature, and this is exactly what the Euro and a good chunk of the SREF is showing. The Euro ensembles came in much better agreement with the OP on this run too, so it may be on to something.

Plus, it's the Euro, and it should make anybody uncomfortable to go against it if it has a meteorologically sound solution, given its verification scores and resolution.

[OceanStWx]

To me, the 12z Euro Ensembles are huge.

There's probably going to be an inverted trough over the central plains, given the pronounced lee-side trough that develops and the decent difference between the relatively mild air ahead of the warm front and the arctic air behind the cold front. This is something the Euro perhaps went overboard with for a couple of days, hence the north track. Now it shows more of a classical system with an inverted trough/weak low that opens into a trough as the southern low becomes dominant. These systems tend to cut towards their inverted troughs as they mature, and this is exactly what the Euro and a good chunk of the SREF is showing. The Euro ensembles came in much better agreement with the OP on this run too, so it may be on to something.

Plus, it's the Euro, and it should make anybody uncomfortable to go against it if it has a meteorologically sound solution, given its verification scores and resolution.

The 15z SREF run is hinting at a pretty good area of snowfall dropping down with the mid level energy, associated with that northern 850 low, before the phase.

[The_Global_Warmer]

To me, the 12z Euro Ensembles are huge.

There's probably going to be an inverted trough over the central plains, given the pronounced lee-side trough that develops and the decent difference between the relatively mild air ahead of the warm front and the arctic air behind the cold front. This is something the Euro perhaps went overboard with for a couple of days, hence the north track. Now it shows more of a classical system with an inverted trough/weak low that opens into a trough as the southern low becomes dominant. These systems tend to cut towards their inverted troughs as they mature, and this is exactly what the Euro and a good chunk of the SREF is showing. The Euro ensembles came in much better agreement with the OP on this run too, so it may be on to something.

Plus, it's the Euro, and it should make anybody uncomfortable to go against it if it has a meteorologically sound solution, given its verification scores and resolution.

The OP Euro by 96 hr has a mature cyclone and is closed off at H7, H8, H5..a classic system.

[Ottawa Blizzard]

What does the Euro imply for Toronto/Ottawa/Montreal?

Remember that the GFs scored a coup back in mid December 2008 when every other model was showing my area warming up to the mid 40s with rain when we ended up with over a foot of snow

[buckeye]

so according to the nam a moderate area of primarily rain in most of IL, IN, and OH at the onset, then there's that storm down in the south that is supposed to ride north and phase in?

[OceanStWx]

Good times...DVN says Euro suffers from convective feedback issues, MKX says it's the Americans.

[jbcmh81]

Good times...DVN says Euro suffers from convective feedback issues, MKX says it's the Americans.

We'll be referencing this model war for years.

[OceanStWx]

That is essentially the root cause of why there "always" seems to be a northwest correction to the models. Runaway latent heating (as a result of convection) artificially lower surface pressures in the models. This is why it is so important to look at QPF with respect to upper level forcing. Does it make sense where the model is throwing the QPF bomb?

[snowstormcanuck]

What does the Euro imply for Toronto/Ottawa/Montreal?

Remember that the GFs scored a coup back in mid December 2008 when every other model was showing my area warming up to the mid 40s with rain when we ended up with over a foot of snow

Just going off the freebies it looks like a mix or rain here in Toronto to start going over to snow. You guys up in Ottawa would probably be all snow.

[Ottawa Blizzard]

Just going off the freebies it looks like a mix or rain here in Toronto to start going over to snow. You guys up in Ottawa would probably be all snow.

It's looking like there will be quite a blast of arctic air behind this storm with rapidly falling temperatures.

[snowstormcanuck]

It's looking like there will be quite a blast of arctic air behind this storm with rapidly falling temperatures.

Areas southeast of Georgian Bay and Lake Huron are going to be crushed v. 2.0.

[on_wx]

Areas southeast of Georgian Bay and Lake Huron are going to be crushed v. 2.0.

Is this type of setup more supportive of LES between London and Barrie? You mentioned elsewhere that last weekend's storm was a... oh what was it... 334/500 storm? Which is typically not supportive of LES around this area I think you said?

[buckeye]

I gotta laugh....I don't care what anyone says....there is a definite backyard bias amongst NWS offices wrt situations like this. I'm not picking on any single region, I think it's pretty much across the board. Below is a clip from BUF:

IT APPEARS VERY LIKELY THAT A STRONG SURFACE LOW WILL

DEVELOP AS A DEEP AND INCREASINGLY NEGATIVE TILTED UPPER TROF ENTERS

APPROACHES THE EAST COAST. THE PART THE MODELS ARE STRUGGLING WITH

IS IF/WHEN/WHERE A COASTAL LOW WILL DEVELOP. STILL FEEL THAT FROM A

CLIMATOLOGICAL STANDPOINT...A COASTAL DEVELOPMENT IS FAVORED GIVEN

THE FAVORABLE BAROCLINIC ZONE ALONG THE EASTERN SEABOARD. WHILE NOT

TOO MUCH IS READ IN THE SPECIFICS...THE OPERATIONAL GFS APPEARS MUCH

MORE PLAUSIBLE THAN THE EUROPEAN/GGEM...AND IS MUCH MORE IN LINE

WITH OUR GOING FORECAST.

[hoosierwx]

Henry Margusity is still talking about this storm transferring to the coast. I haven't seen this anywhere else. Is this supported or just wishcasting?