Pre-Christmas (Dec 21-23rd) Winter Storm Part 2

[cyclone77]

18 minutes ago, Kaner88 said:

0z GFS QPF.

I'm kinda happy to see that little weenie band up by the CR crew.  All their snow will blow down this way by Friday

[btcs31]

Funny to see the local news alerts backtrack on yesterdays forecast totals. ABC7 Alert: Significant changes to our winter storm forecast! Tune in at 10pm.

 

Had family trying to reschedule Friday holiday plans after yesterdays headlines. And I’m talking about a 2 mile trip across town. Imagine by then it will be very cold but manageable conditions.

[Kaner88]

Question becomes, what happens if the Euro goes with the GFS? And to a smaller (but more likely) degree, what do we do if the Euro kinda ticks west to a middle zone between non-GFS 0z guidance and the GFS? Places Chicago in a tricky spot.

 

Edit: Adding to the trickiness is the GFS ENS almost doubling downtown Chicago QPF from the 18z run to ~0.5" through Saturday AM now.

[snowman33]

Just now, Kaner88 said:

Question becomes, what happens if the Euro goes with the GFS? And to a smaller (but more likely) degree, what do we do if the Euro kinda ticks west to a middle zone between non-GFS 0z guidance and the GFS? Places Chicago in a tricky spot.

Winter Storm Warning for 3-7".

[Chicago Storm]

0z UKMET was probably the worse, for everyone, out of the 0z suite.

Much weaker and further east.


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[weathafella]

36 minutes ago, Chicago Storm said:

0z UKMET was probably the worse, for everyone, out of the 0z suite.

Much weaker and further east.


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It’s an awful model regardless of it’s so called verification scores.   I think if I were forecasting based on what I’m seeing I’d go 5-9 for Chicagoland.

[Hoosier]

I'll post more thoughts soon but needless to say, this setup is a pretty sensitive one for Chicagoland and relatively small tweaks could make for a notably more impressive outcome in the area.

[TheNiño]

1 minute ago, Hoosier said:

I'll post more thoughts soon but needless to say, this setup is a pretty sensitive one for Chicagoland and relatively small tweaks could make for a notably more impressive outcome in the area.

Forecasting this storm is going to give me a stroke before it ever even gets here. I’ll take what we can get but it’s painful being so close right now.

[Chicago Storm]

It’s an awful model regardless of it’s so called verification scores.

Yea, it has its moment about once or twice a winter when it’ll have a clue in our region, but outside of that it’s definitely not all that useful.


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[Chicago Storm]

Question becomes, what happens if the Euro goes with the GFS? And to a smaller (but more likely) degree, what do we do if the Euro kinda ticks west to a middle zone between non-GFS 0z guidance and the GFS? Places Chicago in a tricky spot.
 
Edit: Adding to the trickiness is the GFS ENS almost doubling downtown Chicago QPF from the 18z run to ~0.5" through Saturday AM now.

Given the look of the rest of 0z guidance (Including the GDPS), it’s probably safe to toss the GFS/GEFS…Unless some other guidance shifts that way, or the GFS trends away from the idea.


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[Hoosier]

7 minutes ago, TheNiño said:

Forecasting this storm is going to give me a stroke before it ever even gets here. I’ll take what we can get but it’s painful being so close right now.

lol I hear ya.  As others have alluded to, models are having some fits with the handling of the surface low and just where the low really starts to deepen explosively.  This is going to have ramifications for areas near the fringes of the bigger snows.

[Roger Smith]

I saw that attempt at a loop GFS, just like the Euro once had. I think what that loop means is the model recognized the main shot of energy and allowed it to take over from junior out ahead. 

Maybe it will happen that way or maybe there will be more of an organized low coming out of Texas. Might be almost nowcasting the details. Models are still losing the western center after it drops into TX. Isn't there a general tendency for models to underestimate snow potential in the Mississippi valley region? Seems that way over the past few seasons. There was that recent winter with the record snowfalls in Moline, La Crosse and MSP and it seemed like half that snow was not in the forecasts. Was that winter 20-21? (no it was 2018-19 time flies)

[Hoosier]

Although the synoptic setup for this storm is different than the January 26, 1978 blizzard, the end product sort of looks quite similar in a number of respects.

I wouldn't bank on 100+ winds on Lake Erie, but the overall wind footprint should be similar to that 1978 storm.  Don't be fooled by the weaker surface low in this case.  There's a stronger surface high than in 1978, and so the pressure gradient is actually very comparable. 

[Chicago Storm]

0z Euro with a solid jump east and weaker.


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[cyclone77]

Just now, Chicago Storm said:

0z Euro with a solid jump east and weaker.


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We may end up with more blowing dust than snow on Friday lol.

[Chicago Storm]

First and final call, 1.7” ORD.


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[Hoosier]

8 minutes ago, Chicago Storm said:

0z Euro with a solid jump east and weaker.


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Initial thought was that it almost has to be an overcorrection.  Right?  Lol

[cyclone77]

Many of us will be sort of jaded after experiencing the ups and down with this system, so next time there's a big threat it's going to be a little harder to get all that excited about it.  

[cyclone77]

1 minute ago, Hoosier said:

Initial thought was that it almost has to be an overcorrection.  Right?  Lol

Kind of reminds me of a high-end severe threat in the plains that gets ruined by a under-modelled crashing cold front.  

[HillsdaleMIWeather]

Hoping the GFS is somehow sniffing out a coup on this one

[mimillman]

Never thought I’d say it but actually, congrats to the NAM. Sniffed this one out beginning yesterday’s 18s runs, outside of its prime range at that

[cyclone77]

1 minute ago, HillsdaleMIWeather said:

Hoping the GFS is somehow sniffing out a coup on this one

Considering the fact that a few nights ago it dropped a few feet here I'm gonna wager against that outcome.

[Hoosier]

1 minute ago, cyclone77 said:

Considering the fact that a few nights ago it dropped a few feet here I'm gonna wager against that outcome.

At least he has the excuse that the storm is within 2-3 days now.

A global model shouldn't be that bad at 2-3 days in theory.  In theory.

[mimillman]

Just now, Hoosier said:

At least he has the excuse that the storm is within 2-3 days now.

A global model shouldn't be that bad at 2-3 days in theory.  In theory.

Technically it was like 3-4 days out which, it happens. 

[HillsdaleMIWeather]

1 minute ago, Hoosier said:

At least he has the excuse that the storm is within 2-3 days now.

A global model shouldn't be that bad at 2-3 days in theory.  In theory.

I just more am full of hopium in the hopes that you guys further west don't get shut out, I'd take less for more spread the wealth 

[Hoosier]

Just now, mimillman said:

Technically it was like 3-4 days out which, it happens. 

But I mean that we're closer to the storm now.

[mimillman]

1 minute ago, HillsdaleMIWeather said:

I just more am full of hopium in the hopes that you guys further west don't get shut out, I'd take less for more spread the wealth 

We will have our time, don’t worry. And when that happens, it will likely be a nice cold rain for you. 

[hlcater]

Looking at the guidance tonight, receiving most of our snow from FGEN and not the primary low may end up being a blessing in disguise.

[Chicago Storm]

Initial thought was that it almost has to be an overcorrection.  Right?  Lol

Given we’ve seen this trend for over a day now and we continue to approach the event start, would have liked to have seen some reversal for the 0z suite, after the 18z suite stopped the bleeding. Instead we got the opposite, and things have continued to trend worse.

Game, set & match.

[Hoosier]

It's funny, because often times a surface low track from southern IN up through Ohio and toward Detroit will produce just fine in Chicago.  

Then you take that January 1978 storm.  The surface low got so far east (like eastern TN) before turning almost due north and passing around Cleveland, and that thing produces a foot of snow in Chicago.  And it was system snow, not really attributable to lake enhancement.

I think a big issue in this case is the delayed development.  The 1978 storm started bombing much further south.  I would say if we can get the surface low to start deepening rapidly in the Ohio Valley about 6 hours sooner (and maybe just a few hours for LOT's Indiana counties) that it would lead to a substantially snowier outcome in the area.