Pittsburgh, Pa Winter 2023-24 Thread.

[Burghblizz]

Less brutal cold, but more snow on average when looking at more than the last 15 months. Not all that horrible. 

So now that we’ve established that it’s been a mild winter, time to focus on a potential pattern flip.

[CoraopolisWx]

Euro showing some life in the long range. 

[TimB]

2 hours ago, CoraopolisWx said:

Euro showing some life in the long range. 

Heartbreak as depicted, but I think that’s too early to really be our window anyway.

[TimB]

Is it a sign of anything that I just saw a Canada goose flying northward?

[jwilson]

On 2/1/2024 at 2:24 PM, RitualOfTheTrout said:

Another round of blocking might argue the good look sticks around longer than what we had in January, but strong ninos usually favor a warm March so I'm definitely not sold on some 4 week wall to wall winter period setting in either. At least it looks dry AND warm-ish for the next 10 days.

I agree with you here.  This isn't the character of a winter with a longer term sustained cold regime, really.  I suppose we could have something that spurs such an event, like one of the teleconnections goes off on a wild tangent at a significant magnitude and alters the character.  I would suspect the -NAO block isn't stable for a significant period.  Right now I would favor 70/30 odds of a two-week ceiling like we had earlier, meaning 70% chance the block breaks down faster than expected.  The longer-term looks on ensembles could simply be due to the smoothed mean.

The real trepidation for us here is the entrenched block suppressing the big fish to our south or off the coast and the precip shield misses us.  Most likely what's hurt Pittsburgh in previous Nino conditioned winters.  Those blocks can often move the boundary beneath us.  The saving grace is the time of year, perhaps, in that it is happening in late February / early March as opposed to earlier in winter.

Then again, the groundhog told us we'd be in for an early spring.  That should guarantee sustained winter through March.

[CoraopolisWx]

I might be reading this incorrectly. But the long range ridging out west looks impressive, however the inverse trough seems more flat, stretching across the OV into the mid Atlantic. 
Would like to see that trough dig into the mid south at worst.  

[RitualOfTheTrout]

Just posting this 00z GFS solution for some positive energy and morale boost, maybe by this weekend we have something to track besides pretty 500mb patterns?

 

[RitualOfTheTrout]

14 hours ago, jwilson said:

I agree with you here.  This isn't the character of a winter with a longer term sustained cold regime, really.  I suppose we could have something that spurs such an event, like one of the teleconnections goes off on a wild tangent at a significant magnitude and alters the character.  I would suspect the -NAO block isn't stable for a significant period.  Right now I would favor 70/30 odds of a two-week ceiling like we had earlier, meaning 70% chance the block breaks down faster than expected.  The longer-term looks on ensembles could simply be due to the smoothed mean.

The real trepidation for us here is the entrenched block suppressing the big fish to our south or off the coast and the precip shield misses us.  Most likely what's hurt Pittsburgh in previous Nino conditioned winters.  Those blocks can often move the boundary beneath us.  The saving grace is the time of year, perhaps, in that it is happening in late February / early March as opposed to earlier in winter.

Then again, the groundhog told us we'd be in for an early spring.  That should guarantee sustained winter through March.

I think it's inevitable a couple threats are suppressed or shredded if we get the blocking the ENS are showing, but I agree on the time of year, by the last week of Feb into early March, a healthy STJ wave might need some extra help to keep it under us. 

My thoughts on how things evolve would be along these lines: If we can score anything in the Feb 12th - 16th period that would be a bonus (threat the needle / marginal air mass type deal), then the blocking likely pushes most threats to far South 17th-22nd (illustrated in precip anomalies etc.) then 23rd - 29th (Yes don't forget we get an extra day of Feb this year for those worried about the calendar ) might be the first shot at a bigger storm. After that maybe a repeat of that cycle in some form for early March depending how blocking evolves, stuff above my pay grade (weak SPV coupling / MJO progression etc.) might argue for a second round of blocking to re-establish.

The deep winter enthusiast in me would prefer this all to be happening a month earlier, but on the other hand if you want to go all in on a "Max Bet" with a good pattern in early March might be the best shot for those big game hunting. Good pattern doesn't guarantee anything, still chaos / luck involved to get something to work out.

[TheClimateChanger]

 

[TheClimateChanger]

For the record, I was playing around with the AWSSI last week, and 1997-1998 is the current full-season record low. Last winter appeared to be the second least. It's not a particularly easy tool to find rankings, but I checked several of the dud winters since 1950. It looks like the cold snap just before Christmas prevented last year from being the record low.

[north pgh]

Tuesday and Sunday of next week may be our best chance of landing a good snowfall. At least we can start tracking again maybe.

[Ecanem]

NWS just confirmed we are behind last years snowfall. I know we had a few bigger hits this year and last year was some miserable trickles but it’s crazy we are behind even last year.

[CoraopolisWx]

21 minutes ago, north pgh said:

Tuesday and Sunday of next week may be our best chance of landing a good snowfall. At least we can start tracking again maybe.

Not a bad look overall, just gotta make sure that 850 low doesn't go any further north.

[Rd9108]

42 minutes ago, CoraopolisWx said:

Not a bad look overall, just gotta make sure that 850 low doesn't go any further north.

Call me a Debby downer but this such a thread the needle event. If a big phase happens there's nothing to keep this going to Youngstown. 

[RitualOfTheTrout]

1 minute ago, Rd9108 said:

Call me a Debby downer but this such a thread the needle event. If a big phase happens there's nothing to keep this going to Youngstown. 

We need some phase to get the NS involved though to get the cold, 6z GFS was really close to perfect, get that whole progression to happen a little faster and further SW and it bombs right over us vs central PA and look out. There in lies the the thread the needle aspect though, there aren't any other features to buy wiggle room, so it all has to time out perfectly which makes it even lower odds than normal.

But dang... 

[Rd9108]

23 minutes ago, RitualOfTheTrout said:

We need some phase to get the NS involved though to get the cold, 6z GFS was really close to perfect, get that whole progression to happen a little faster and further SW and it bombs right over us vs central PA and look out. There in lies the the thread the needle aspect though, there aren't any other features to buy wiggle room, so it all has to time out perfectly which makes it even lower odds than normal.

But dang... 

And maybe we get lucky. The ensembles atleast show us with some snow which is nice to see for a change. 

[Rd9108]

Cutting even more this run. This far out there's no point in getting hung up about global runs. Regardless we track. 

[CoraopolisWx]

Gfs can't decide between a bloated 850 low and a more compact version.

[Rd9108]

Just now, CoraopolisWx said:

Gfs can't decide between a bloated 850 low and a more compact version.

Yeah and we are still like 5 days out so a lot can change. I just don't like that there's not a lot that prevents this from cutting. 

[north pgh]

I think regardless of whether we can land something Tuesday, The cold NW flow kicks in the rest of the week. At this point I'd be happy to see a clipper move in during this time. 

[TheClimateChanger]

I know most here don't like data, but I had to re-run the numbers through six days of February torch - and it's not pretty. Up to 4th place now, matching the highest of any winter to date since 1931-32 [downtown city office], and a full 2 degrees warmer than any year at KPIT (2016 & 2002). And it looks like the rest of this week will likely be even warmer, especially with overnight lows.

[TheClimateChanger]

4 hours ago, RitualOfTheTrout said:

We need some phase to get the NS involved though to get the cold, 6z GFS was really close to perfect, get that whole progression to happen a little faster and further SW and it bombs right over us vs central PA and look out. There in lies the the thread the needle aspect though, there aren't any other features to buy wiggle room, so it all has to time out perfectly which makes it even lower odds than normal.

But dang... 

This would be swell. 

[north pgh]

Euro has the storm as well. 

Storm is there. Now it will be a matter of track and precip type and amounts. I am sure that there will be ups and downs through the next 3-4 days.

[TimB]

This is the second time on record and first since 1878 that the first 7 days of February have featured exactly zero measurable precip. In 1878, there was measurable precip on the 8th. At this juncture, no model is showing precip before midnight tomorrow night, so we may make history.

[Rd9108]

3 minutes ago, TimB said:

This is the second time on record and first since 1878 that the first 7 days of February have featured exactly zero measurable precip. In 1878, there was measurable precip on the 8th. At this juncture, no model is showing precip before midnight tomorrow night, so we may make history.

And this weather in no way is depressing. I'll take this over 40s and rain or 20s and dry. 

[jwilson]

The storm around Valentine's Day was what I expected to be our initial cutter that helped set the pattern going forward.  Others have already said it, but if we want that one to be snow, we need perfect timing of the phase.  I don't generally like betting on those types of storms because of all the ways they can fall apart.  That doesn't mean it can't happen, however.  If it does miss, I don't think it's a big deal in the grand scheme of things.  If we get a hit, that's a massive bonus.

The question is what happens after, because right now the OP models are sort of kicking the idea of an established -NAO.  The ensembles still seem to have it in the long range, but it's not developing in the same way it was before.  If you go back in time, you can see the ensembles started establishing the -NAO around the 17th after the bowling ball shortwave resets the table.  The latest runs push it to the 20th and it's a retrograded Scandinavian block instead.  Maybe this is delayed instead of cancelled, but it's enough to raise an eyebrow.

The OP GFS isn't showing a -NAO at all, even in fantasy land.  Now the GFS has been particularly bad this year, but the Euro and Canadian only give a faint appearance at the very end of their latest respective runs.  We're going to have to wait a bit longer for resolution.

Now that's all "meta" pattern talk and not necessarily relevant to the individual storm threats we may face. 

Right now, the President's Day threat looks like a classic Miller A, but it's fairly basic overrunning wave that gets squashed by the NS plunge.  There's zero interaction between the two streams.  Verbatim that event has a capped ceiling.  It's northward progression is dependent upon timing and strength of the cold boundary.  Unfortunately, you have those two lower pressures sinking at the same time, with the energy in the southwest shrinking away from the NS, instead of say a basic western ridge that forces the NS energy down into the CONUS. 

In the north, it's a classic Rex Block.  That stalls that cold air bubble a bit longer rather than allowing it to make West-East progress and get out of the way.

What I'm perhaps most interested in, for now anyway, is what happens after the PD event.  It looks wonky in the interim, but it won't resolve that way and ultimately doesn't matter quite yet.  If you freeze the 12Z OP GFS at 300 and overlay with the ensembles, you can see the potential.

I do think it's also possible, however, we end up kicking a better established pattern into March.  And I hate to phrase it that way but this is the danger of long-term tracking.  The good news for now, even if that happens, we have threats to watch.

[Ahoff]

2 hours ago, TimB said:

This is the second time on record and first since 1878 that the first 7 days of February have featured exactly zero measurable precip. In 1878, there was measurable precip on the 8th. At this juncture, no model is showing precip before midnight tomorrow night, so we may make history.

February is a historically drier month to begin with, but after a really wet January, we could use some dry time, then hopefully buckle in for a wild back half of the month.

[Rd9108]

Still a long long way out

 

[blackngoldrules]

Still a long long way out

 

I noticed that the Kuchera has it at 4.3 inches. Is it picking up on this maybe being a low ratio snowfall?

Sent from my SM-G991U using Tapatalk

[TheClimateChanger]

8 hours ago, Rd9108 said:

Still a long long way out

 

What’s it look like with Kuchera ratios? Kuchera ratio maps used to throw up massively inflated totals, but I’ve noticed over the past couple of years, they have often been less than the 10:1 maps.