Western PA/Pittsburgh Winter 2021/22 Discussion

[meatwad]

Thread for the Winter 2021/22 season.

[jwilson]

Thanks!  I had some thoughts / predictions for the winter.

I went back and looked at all the years with back-to-back Nina episodes.  There wasn't much of a constant or pattern.  Some years were lean (<30") while others were fine (>50").  Obviously, last year we did well, particularly in December, and then by March the winter was over.  I think this year is probably going to be the inverse of that, with more of our snow coming in February and perhaps March, but it remains a coin-flip month.  Overall, I don't think we're looking at much.  My guess is the official Pittsburgh measurement is between 25-35".  Granted, the high end of that is close to normal, not exactly a bad winter, per se, but I instinctively pull toward the low-end.

Areas south will do worse, as is typical.  I "only" measured 38.2" last season compared to Pittsburgh which was well over 50 inches.  As in a Nina, we aren't likely to see a ton of southern-jet (STJ) activity.  We're looking at a northern stream dominant winter, with clippers and lake effect the predominant means of snow makers.  I don't really foresee a 10"+ storm, but guessing that this far out means I don't have much confidence.  I could certainly be wrong.  Pittsburgh isn't as sensitive to Nina winters as some places in the East that rely on coastals.

The December outlook isn't bullish.  I think this is one of those winters where we lead into Christmas week with 50s, maybe even 60s on occasion.  Not exactly the best "winter holiday" feel.  I prefer cold and snowy, of course, but that combination in December is uncommon for all the places I've ever lived.  We probably come out of December with <5" of snow total.  Then you have a brief pattern breakdown either around New Years or early January before it is back to a warmish look (40s to 50s).  As I said, I think the best chance for snow is February once we begin to bring down the Nina from its peak and push back toward neutral.  We might still finish warm each month, but that doesn't mean we'll get shutout.

I could be 100% wrong on all of this so take it with a grain of salt.  Just my predictions based on teleconnections, experience, and the overall worldview as it stands right now.  As a snow lover, I certainly hope I'm wrong.

[CoraopolisWx]

Looks like the bill is due for last years epic December. 
Hopefully this increasingly  positive AO heads back toward neutral sooner than later, to give us a shot at something track able. 

[TimB]

The thing to remember here is, yes, we have a lot of garbage Decembers around here. However, I just looked at the past 40 years of snowfall data by month and something stood out to me. If you define a “garbage December” or “garbage winter” as one with below normal snowfall, there have been only two garbage Decembers that didn’t eventually end up as garbage winters: 2004-05 and 2014-15. And 2004-05 was barely below normal in December (7.3”, normal is 7.7”). So 2014-15 stands out as the only recent “crappy December, decent winter” year (0.2” in December, 47.5” for the winter). So yes, a bad December is often the death knell for an average or above snowfall winter.

[RitualOfTheTrout]

On 12/1/2021 at 2:13 PM, jwilson said:

Thanks!  I had some thoughts / predictions for the winter.

I went back and looked at all the years with back-to-back Nina episodes.  There wasn't much of a constant or pattern.  Some years were lean (<30") while others were fine (>50").  Obviously, last year we did well, particularly in December, and then by March the winter was over.  I think this year is probably going to be the inverse of that, with more of our snow coming in February and perhaps March, but it remains a coin-flip month.  Overall, I don't think we're looking at much.  My guess is the official Pittsburgh measurement is between 25-35".  Granted, the high end of that is close to normal, not exactly a bad winter, per se, but I instinctively pull toward the low-end.

Areas south will do worse, as is typical.  I "only" measured 38.2" last season compared to Pittsburgh which was well over 50 inches.  As in a Nina, we aren't likely to see a ton of southern-jet (STJ) activity.  We're looking at a northern stream dominant winter, with clippers and lake effect the predominant means of snow makers.  I don't really foresee a 10"+ storm, but guessing that this far out means I don't have much confidence.  I could certainly be wrong.  Pittsburgh isn't as sensitive to Nina winters as some places in the East that rely on coastals.

The December outlook isn't bullish.  I think this is one of those winters where we lead into Christmas week with 50s, maybe even 60s on occasion.  Not exactly the best "winter holiday" feel.  I prefer cold and snowy, of course, but that combination in December is uncommon for all the places I've ever lived.  We probably come out of December with <5" of snow total.  Then you have a brief pattern breakdown either around New Years or early January before it is back to a warmish look (40s to 50s).  As I said, I think the best chance for snow is February once we begin to bring down the Nina from its peak and push back toward neutral.  We might still finish warm each month, but that doesn't mean we'll get shutout.

I could be 100% wrong on all of this so take it with a grain of salt.  Just my predictions based on teleconnections, experience, and the overall worldview as it stands right now.  As a snow lover, I certainly hope I'm wrong.

Thanks for sharing your thoughts, I tend to agree odds favor a below average snowfall winter given everything we can see right now. There is always the chance mother nature throws a curve ball, and even in a lousy pattern brief interludes of something favorable as things re-shuffle and re-establish the lousy base state can yield a few windows of opportunity, and if you get lucky with a few storms during those windows then even though your general thoughts on the winter pattern were correct from a pure numbers standpoint maybe it doesn't look like that bad of winter at the end of the season.

On 12/1/2021 at 2:16 PM, CoraopolisWx said:

Looks like the bill is due for last years epic December. 
Hopefully this increasingly  positive AO heads back toward neutral sooner than later, to give us a shot at something track able. 

Not a big fan of a crap pattern getting established during December in a La-Nina which typically favors colder and snowy starts. Maybe the "front loaded" portion of Winter was the end of November snow and cold.. I hope not.

On 12/1/2021 at 2:47 PM, TimB84 said:

The thing to remember here is, yes, we have a lot of garbage Decembers around here. However, I just looked at the past 40 years of snowfall data by month and something stood out to me. If you define a “garbage December” or “garbage winter” as one with below normal snowfall, there have been only two garbage Decembers that didn’t eventually end up as garbage winters: 2004-05 and 2014-15. And 2004-05 was barely below normal in December (7.3”, normal is 7.7”). So 2014-15 stands out as the only recent “crappy December, decent winter” year (0.2” in December, 47.5” for the winter). So yes, a bad December is often the death knell for an average or above snowfall winter.

Overall I think this makes sense, from a statistical standpoint if you start off below average in the beginning with snow then you need some above average hits later on to make up for it, which with La-Nina favoring an early start to Winter puts you even further behind the 8 ball for later months to make up for a bad start vs say an El-Nino with typically less snowy starts and but a solid chance later in the season. We can always hope that since the start is not typcial La-Nina maybe the middle and end won't be either.

It's going to be hard to beat last year in any of the upcoming years in my book for a great December, big storm on the 16th, then another storm on Christmas Eve and a white Christmas is about as good as it gets. As I get older its easier to just have an "it is what is" attitude towards this hobby, when I was younger I'd let emotions get the best of me, and after all when you wait all year for snow storm tracking and you get nothing who wouldn't be disappointed, but that's the price of admission for something we have zero control over. Anyways, hey, look outside its snowing now.

[Ahoff]

As much as I want snow, and of course I do, I have to fly on Wednesday, and that looks like a weather day, whether it's rain or snow.  Just hope it either finishes before my flight or holds off until after take off.

[Ahoff]

Maybe there's a chance.

[donyewest]

Every model, including hourly refreshes and official KPIT forecast, undershot temperature performance today.  I'm highly inclined to believe the 20+ above average temps for frontal passages shown under both GFS and Euro for 12/6 12z and 12/11-12/12 weekend.  Gonna be warm (for winter) and rainy or seasonably cold and dry for the next few weeks.  Kinda shaping up like our wild October with way above average temps and strong gradient b/t warm sector and cold fronts.  Makes me wonder if we'll see some strong storms out of it.

Perfectly good waste of a wintertime -QBO.

[Gordo74]

Any thoughts on Wednesday?

 

Quiet forum this year.

[TimB]

12 minutes ago, Gordo74 said:

Any thoughts on Wednesday?

 

Quiet forum this year.

Wednesday looks DOA at this point. And it’s hard to buy what some runs of the operational models are trying to sell for the upcoming weekend when they are so badly out of sync with the ensembles. We need a massive pattern change.

[TimB]

Our last 2” snowfall was February 9th. Today will be day #299 without a 2 inch or more snowfall, which will rank 24th all time. Get to 316 and we crack the top 10, which currently includes 4 different times this century.

[jwilson]

1 hour ago, TimB84 said:

Wednesday looks DOA at this point. And it’s hard to buy what some runs of the operational models are trying to sell for the upcoming weekend when they are so badly out of sync with the ensembles. We need a massive pattern change.

Agree.  The thing on Wednesday looks like a pretty flat, progressive wave that will pass fairly well south of us.  Heights are pumping a little bit out west, but the location of the ridge isn't ideal and honestly, it's not dramatic enough to make me look twice.  The flow is quick from there and the eventual developed low doesn't start bombing until it is well off the coast, and not even all the models have that kind of development.  Maybe Coastal Maine could see something.  It's still too fast to be much of a producer.

[Gordo74]

Great discussion! 

[PghPirates27]

We are toast for a while through at least next week. High temps In the 40s and lows above freezing.

An outside shot maybe Sunday But I’m not holding my breath lol.

hopefully the outlook changes but soon it’s gonna be January without much to speak of.

[jwilson]

The very end of the GFS run, out in fantasy land, tries to get us into a cold look Christmas week.  It's not a stormy look, more cold and dry, but at least it would feel seasonal.

The MJO is possibly trending in the right direction, so it has some support.  Phase 7 --> Phase 8.  The only problem is that's the only thing on our side for the time being.

[donyewest]

This weekend is going to be massively gross, no doubt we hit 60+ degrees (more I learn, more I respect the Penn State meteo program):

 

As far as the remainder of the month, Dr. Cohen performs fantastic analysis on his blog (esp. during winter) and he's from the NE so we're on the fringe of his personal bias highlights:

Edit because it would help if I added the link to his blog: https://www.aer.com/science-research/climate-weather/arctic-oscillation/

[TimB]

Saw yesterday that the 90% probability of above normal temperatures area (which includes all of Western PA) on the CPC Day 8-14 outlook is the largest such area since 12/15/2015. We get this pattern in El Niño years, we get this pattern in La Niña years, so it’s almost like something else is driving it. But I’m not sure what it could be.

[dj3]

6 minutes ago, TimB84 said:

Saw yesterday that the 90% probability of above normal temperatures area (which includes all of Western PA) on the CPC Day 8-14 outlook is the largest such area since 12/15/2015. We get this pattern in El Niño years, we get this pattern in La Niña years, so it’s almost like something else is driving it. But I’m not sure what it could be.

Hadley cell? Haha, I read in the New England forum enough that I had to insert the joke. 

[dj3]

21 minutes ago, TimB84 said:

Saw yesterday that the 90% probability of above normal temperatures area (which includes all of Western PA) on the CPC Day 8-14 outlook is the largest such area since 12/15/2015. We get this pattern in El Niño years, we get this pattern in La Niña years, so it’s almost like something else is driving it. But I’m not sure what it could be.

I think the base state of the pacific being crap for the last several years is the direct reason for less frequent and less intense cold intrusions. Is that something we will see more often than not with a changing climate? I don't have enough knowledge to have a clue. Anecdotally, I find it funny that we used to worry about the warm tongue all the time as our big problem and in the last few years there haven't been as many slop storms to worry about mixing. 

[donyewest]

On 12/7/2021 at 1:17 PM, TimB84 said:

Saw yesterday that the 90% probability of above normal temperatures area (which includes all of Western PA) on the CPC Day 8-14 outlook is the largest such area since 12/15/2015. We get this pattern in El Niño years, we get this pattern in La Niña years, so it’s almost like something else is driving it. But I’m not sure what it could be.

This is actually a good explainer on what's going on, I read the referenced research paper and it was pretty interesting (cited on 4th picture):

 

[jwilson]

The timing of this change will really depend on the momentum of the MJO.  Right now, it is basically stationary in Phase 6.  The GFS wants to advance it quickly once into Phase 7 through Phase 8, but if the slow propagation continues in our prime cold phases (7, 8, 1), that's actually a good thing for our snow chances.  You can see this on the 6Z GFS, especially.  It dumps cold air into the CONUS midweek (21st/22nd).  We'll see if that continues, but it has waffled a little between a warm week and a cold one.  The flow of that wave will probably dictate if we get transient cold or can retain it.

The Euro is much slower with the forward propagation of the MJO.  It keeps us in a warmer pattern perhaps a week longer than the GFS.  This is the old "delayed but not denied" mantra.  It remains to be seen what kind of amplification the MJO wave will have; it certainly looks high enough to be a pattern-driver.  I think the only question is a matter of timing, but really there's no guarantee it moves as the GEFS projects.  We've seen these long-range looks fail in past winters.  This isn't quite the same situation but nonetheless, you can't make bets.

I'd say Christmas week might still be closer to 50/50 odds of cold or warm, maybe even favoring warmth just slightly, but New Year's would favor cold in the opposite (60/40).

[donyewest]

The problem is that the MJO long-term forecasts typically verify poorly, it's difficult to trust anyone making a call >1.5-2 weeks out.  25% error (being generous here) from a key model component cascades into complete garbage output.  Multi-member ensembles do better, trying to monte carlo out a solution, but even those are subject to long-term weirdness.  Honestly, the MJO is dang frustrating.  I think it was 2019-2020 winter where the convection didn't budge to a favorable phase until winter was over.  Just hung out to irritate us.

[north pgh]

After last years great December for snowy weather and a White Christmas, it looks like this year will be a bust. So far I am okay with that.  Let's hope we can get a normal snowfall year of 40 inches or so in January and February. I would take that in a heartbeat. Here's hoping. 

[ChalkHillSnowNut]

8 hours ago, north pgh said:

After last years great December for snowy weather and a White Christmas, it looks like this year will be a bust. So far I am okay with that.  Let's hope we can get a normal snowfall year of 40 inches or so in January and February. I would take that in a heartbeat. Here's hoping. 

Thanks for posting!! Been crickets due to no threats-hope u all have an awesome Christmas!

[TimB]

Would think today’s record high of 64 is in play if we get some sun. Last year, PIT set a record snowfall of 9.3” on today’s date. What a difference a year makes.

Edit: looks like 64 was reached just after noon.

[Gordo74]

Looks like potentially a very very slim chance of a dusting in Christmas evening?

[donyewest]

On 12/4/2021 at 2:36 PM, donyewest said:

Gonna be warm (for winter) and rainy or seasonably cold and dry for the next few weeks.

Just throwing this back out here 'til we actually get snow.  Didn't NWS say that we're on track for top 10 lowest December totals?  Yay. 

[blackngoldrules]

Hey guys. Haven't posted in here in a long time. I've had some personal battles I've been dealing with and it's kept me from my hobbies. Anyway, this winter looks like it may be a reversal of last winter. Hopefully if we're starting off slow, we'll finish strong. Can't say I mind days like this if it's not going to snow. Hate cold and dry. Anyway, take care guys and hopefully things pick up soon.

Sent from my SM-G991U using Tapatalk

[PghPirates27]

Looks like the week between x-mas and new years is trending warmer. Been watching it for the last week. Since Last Tuesday the average temp in the forecast for the week of 12/26 has gone up 7 degrees for the high and 8 degrees for the low. Now looking like all highs in the 40's all of next week through new years. Still early but looking on the warmer side.

If it's going to be in the 40's I'll take it along with the sunshine.

[Rd9108]

All it takes is one Feb 5 or Jan 1994 storm and I'd be happy. If it's notngonna snow I would rather it be warm.