Pittsburgh, PA/Western PA Fall/Winter Discussion 2022-23

[CoraopolisWx]

Same here, woke up to a surprise covering. 
Looks like around 530 a rogue band moved through the south hills. 

[Ahoff]

00z GFS mean is pushing 6" for Allegheny Co.

[Ecanem]

Back for another fun season.  

It looks like the models still don't have consensus on this thing. 

 

ICON has this much further east and faster.

Euro is faster and West 

GFS is west but slower 

CMC looks like it still wants to transfer off the coast.  

Obviously the bullseye a week out is bad.  With that said, we have seen these things shift massively with just days notice.  The energy for this looks like its not coming until Tuesday/Wednesday which means we have a lot of shifts to come. 

[Rd9108]

Looks like this thing will wanna cut to Wisconsion at this point if it keeps trending the short wave to dig deeper. SMH like I said cutters never trend better they just don't. Pretty amazing actually 

[Rd9108]

I need a break from this models after the week I just had. They are making me lose my mind. I should know better too but I wanted some good news this weekend. 

[CoraopolisWx]

Looking like a classic undercut storm, were areas further SE of the low will change over faster, than folks closer to the path of the low. 
Just a matter of how much moisture wraps in behind ?

[RitualOfTheTrout]

2 hours ago, CoraopolisWx said:

Looking like a classic undercut storm, were areas further SE of the low will change over faster, than folks closer to the path of the low. 
Just a matter of how much moisture wraps in behind ?

Yeah, I've kept expectations in check since it was the GFS vs the world a few days ago. At this point should still be a pretty intense change over with winds ripping too. It's clear it's going to be west, but as you said it being further NW now is probably better for our chances than a near miss.

I think we should still manage a 1-3 type event if that wrap around / lake enhancement. Might even be doable to see a 3-5 inch type setup.

[Ahoff]

13 minutes ago, RitualOfTheTrout said:

Yeah, I've kept expectations in check since it was the GFS vs the world a few days ago. At this point should still be a pretty intense change over with winds ripping too. It's clear it's going to be west, but as you said it being further NW now is probably better for our chances than a near miss.

I think we should still manage a 1-3 type event if that wrap around / lake enhancement. Might even be doable to see a 3-5 inch type setup.

Yeah, I mean the changeover was always an option.  It was consistently modeled when the storm has been west.  I still have faith we get a few inches from this.  Our ceilings aren’t too high usually anyway.  6” is probably the max now.

[TimB]

3” would be acceptable. 1-2 would be a gut punch.

[dj3]

22 minutes ago, TimB said:

3” would be acceptable. 1-2 would be a gut punch.

Good luck with the wrap around 

[dj3]

It is crazy that people way smarter than me don’t see what’s happening. Last cutter was modeled to have some snow behind. Maybe we get what we got last night. That’s a huge disappointment 

[dj3]

At least our epic pattern is breaking down the day after Christmas. Melt complete 

[Ahoff]

24 minutes ago, dj3 said:

It is crazy that people way smarter than me don’t see what’s happening. Last cutter was modeled to have some snow behind. Maybe we get what we got last night. That’s a huge disappointment 

Is this really the exact same kind of system, though?  It's a cutter, but this one has arctic air rushing in behind, the last one didn't.  If it comes in right we could get some snow.

[TimB]

44 minutes ago, dj3 said:

At least our epic pattern is breaking down the day after Christmas. Melt complete 

Saturday, Sunday and Monday will be cold with an inch of snow on the ground. What, you wanted more from this winter?

[Rd9108]

Sheesh gfs cuts this over to Chicago now. So much for any semblance of an east trend. Hopefully we can score a few inches from the front but I wouldn't expect much.

[Burghblizz]

36 minutes ago, Rd9108 said:

Sheesh gfs cuts this over to Chicago now. So much for any semblance of an east trend. Hopefully we can score a few inches from the front but I wouldn't expect much.

I think more backend than front…

It cuts and cuts hard - but it wraps a lot of cold air around it with SLP way west - and a good slug of moisture still. Gives my backyard about 10” if taken literally, but also some far lessor amounts close by. 

Rain, rapid temp drop, maybe a flash freeze, and then a period of SN+ looks quite possible. Hard to be too excited when there is a raging blizzard in the Midwest, but does still have a chance to be eventful. 

[olafminesaw]

Any thoughts on travel Friday afternoon/early evening? Seems temps will be in the low 20s at that time, although the timing of the front is still TBD. At what temp would you expect roads to freeze solid? 

[TimB]

The problem I’m seeing with the back end snow potential is that the Euro, which sniffed out the cutter in the first place long before the GFS did, has started a disturbing trend of virtually no snow on the back end (about 1” on the 0z). For what it’s worth, the UKMET agrees with this garbage. So do the It’s probably prudent to lower our expectations yet again.

Edit: with the exception of the GEFS, the ensembles are on board with this solution too. Probably the biggest gut punch since 1/19/19.

[Ahoff]

8 hours ago, Burghblizz said:

I think more backend than front…

It cuts and cuts hard - but it wraps a lot of cold air around it with SLP way west - and a good slug of moisture still. Gives my backyard about 10” if taken literally, but also some far lessor amounts close by. 

Rain, rapid temp drop, maybe a flash freeze, and then a period of SN+ looks quite possible. Hard to be too excited when there is a raging blizzard in the Midwest, but does still have a chance to be eventful. 

This seems similar to Christmas Eve/Day 2020.  Warm/rain, to snow and cold.  That turned out well.

[Ahoff]

46 minutes ago, TimB said:

The problem I’m seeing with the back end snow potential is that the Euro, which sniffed out the cutter in the first place long before the GFS did, has started a disturbing trend of virtually no snow on the back end (about 1” on the 0z). For what it’s worth, the UKMET agrees with this garbage. So do the It’s probably prudent to lower our expectations yet again.

Edit: with the exception of the GEFS, the ensembles are on board with this solution too. Probably the biggest gut punch since 1/19/19.

With as quickly as the cold is supposed to be pouring in, I'd be surprised if it didn't catch up to the precip or out run it for a time.

[TimB]

2 minutes ago, Ahoff said:

With as quickly as the cold is supposed to be pouring in, I'd be surprised if it didn't catch up to the precip or out run it for a time.

The Euro solution has us dry slotting just in time for the potential snow. GFS also has the dry slot feature, but it’s still in a location where we can get some snow.

[jwilson]

Congrats to Davenport, IA and Milwaukee.

We're back to an arctic front which is ironically what this system looked more like originally.  Problem seems to be we're getting ridging out ahead of the system instead of an LP in the Maritimes which would suppress the flow.  Not exactly atypical of a Nina.

This is why the big ones are so elusive.  Too many things to get right, while getting one thing wrong is easy and messes up the entire formula.

The GFSE mean is 3-5" in Western PA, but it's sort of on its own.  I think the ground will be slightly white on Christmas, just not the exciting version.

[Rd9108]

 

From the 2020 thread

GFS (and other models) are showing a wave of low pressure develop and ride up along the strong cold front projected to move through. It's all heavily timing dependent, front has to clear just as the wave moves past your latitude then deepen and slow the progression of the front to see those big totals. Don't get invested in anything you see with this, it won't be resolved until very short lead times. 

 

That's the difference in 2020. This is a totally different set up

[olafminesaw]

36 minutes ago, TimB said:

The Euro solution has us dry slotting just in time for the potential snow. GFS also has the dry slot feature, but it’s still in a location where we can get some snow.

Seems the difference is in the tilt of the trough. The Euro is much more positivity tilted, while the GFS is close to neutral

[Homie J]

Is there any other storms beyond this Christmas storm which clearly will not produce much if anything for our region? 

[TimB]

Am I the only one who isn’t all that impressed with the magnitude of the cold even behind the frontal passage? With the lack of snow cover, NWS is already going high on temps for the holiday weekend. Highs in the upper teens and lows in the upper single digits. Meh. We got cold of that magnitude pretty much every winter up until the last few winters when it became nearly impossible to get a high below 20.

[TheClimateChanger]

13 minutes ago, TimB said:

Am I the only one who isn’t all that impressed with the magnitude of the cold even behind the frontal passage? With the lack of snow cover, NWS is already going high on temps for the holiday weekend. Highs in the upper teens and lows in the upper single digits. Meh. We got cold of that magnitude pretty much every winter up until the last few winters when it became nearly impossible to get a high below 20.

I guess it's fairly impressive for late December. Current point-click centered on Pittsburgh International Airport has 15 for Christmas Eve, and 17 for Christmas Day, which would be the 2nd and 5th coldest max temperatures on record. Especially with the trend towards warmer Decembers. Midnight highs can always effect those figures, but looking at the timing of the cold front, I don't see that being an issue.

[RitualOfTheTrout]

1 hour ago, Rd9108 said:

 

From the 2020 thread

GFS (and other models) are showing a wave of low pressure develop and ride up along the strong cold front projected to move through. It's all heavily timing dependent, front has to clear just as the wave moves past your latitude then deepen and slow the progression of the front to see those big totals. Don't get invested in anything you see with this, it won't be resolved until very short lead times. 

 

That's the difference in 2020. This is a totally different set up

Yes, this setup doesn't have a wave riding up the front, so good to point out this is a different animal.

[Rd9108]

I think it's time to just hope for 1-3 somehow and enjoy a White Christmas. It can happen but we need some help especially with this just trending west and west 

[TimB]

3 minutes ago, TheClimateChanger said:

I guess it's fairly impressive for late December. Current point-click centered on Pittsburgh International Airport has 15 for Christmas Eve, and 17 for Christmas Day, which would be the 2nd and 5th coldest max temperatures on record. Especially with the trend towards warmer Decembers. Midnight highs can always effect those figures, but looking at the timing of the cold front, I don't see that being an issue.

Yeah, looks like the front comes through early enough that at least we don’t get midnighted on Saturday. I’m just concerned that we overperform if we get any sunshine and no snow cover. I didn’t realize the low max for Christmas Eve was so attainable (13). I knew about the 0 on Christmas 1983, but I didn’t realize just how impressive that was. Looks like the next coldest December high in the last 100 years was 7.