November Medium/ Long Range

[WxUSAF]

Worth pointing out/reminding that something like the gfs shows with strong highs moving to our north and a broad flat eastern trough is way better for snow chances than something like that GGEM shows, which is a cold upper low diving southward. 

[NorthArlington101]

Pretty good look for late November. Not sure the CAD will hold but it’ll trend better

It actually mostly held. Crushed by November standards. Only nine days!

[WxUSAF]

@psuhoffman, yeah not sure. My limited understanding is that QBO phase supports or detracts from high latitude blocking frequency. Webb, at least, is clearly NOT expecting a weak strat PV and strongly -AO. Quite the opposite. So not sure how QBO would make that even worse?

[BristowWx]

7 minutes ago, NorthArlington101 said:

It actually mostly held. Crushed by November standards. Only nine days!

taking 11/11/87 out of the equation that would be epic snowfall for November.  

[brooklynwx99]

23 minutes ago, psuhoffman said:

Honest question... I really do wonder what you or anyone else's take on this is.  I do see these posts from some VERY knowledgeable experts and I certainly see the pattern coming up...and I want to be hopeful...but almost all the analogs they are using to justify the optimism are based on years where the QBO was totally opposite of this year.  There are no examples of a snowy winter with a similar enso/QBO/PDO combo as we are in right now.  None!  

 

So I guess my question is...am I missing something?  It is a small sample...maybe the QBO isn't as important in this equation as I am making it.  I do lean towards this not being a blowtorch wall to wall...some of my top analogs were decently cold winters...but not snowy at all.  Example 2008-9 is a top analog.  And look at the pattern late Nov to early Dec that winter...but it didn't help us at all, it was a horrible snowfall year here.  

Thoughts? 

 

2013-14 has been a good analog for a while. high solar, too

[brooklynwx99]

been a long time since I've seen a SE ridge get squashed in the medium range

[Terpeast]

20 minutes ago, brooklynwx99 said:

been a long time since I've seen a SE ridge get squashed in the medium range

Also looks like remnants of a STJ from last year’s el nino

[brooklynwx99]

3 minutes ago, Terpeast said:

Also looks like remnants of a STJ from last year’s el nino

models are advertising +AAM with is unusual for -ENSO. wouldn't be shocking considering a top 5 Nino last year

[TSSN+]

Seems like ens pretty juicy 

 

[NorthArlington101]

12Z EURO (which now kicks off around 12:10 instead of 12:45!) has a significant storm in the same timeframe. Not as friendly a look, but very trackable.

[psuhoffman]

49 minutes ago, brooklynwx99 said:

2013-14 has been a good analog for a while. high solar, too

It's a good enso/solar analog, but not in any of the other metrics I looked at.  But that is why I am asking this...maybe I am weighting things people think don't actually matter.  

[cbmclean]

1 hour ago, psuhoffman said:

Honest question... I really do wonder what you or anyone else's take on this is.  I do see these posts from some VERY knowledgeable experts and I certainly see the pattern coming up...and I want to be hopeful...but almost all the analogs they are using to justify the optimism are based on years where the QBO was totally opposite of this year.  There are no examples of a snowy winter with a similar enso/QBO/PDO combo as we are in right now.  None!  

 

So I guess my question is...am I missing something?  It is a small sample...maybe the QBO isn't as important in this equation as I am making it.  I do lean towards this not being a blowtorch wall to wall...some of my top analogs were decently cold winters...but not snowy at all.  Example 2008-9 is a top analog.  And look at the pattern late Nov to early Dec that winter...but it didn't help us at all, it was a horrible snowfall year here.  

Thoughts? 

 

As far as Webb, I didn't take that particular post of his as necessarily being optimistic, just noting some potential interest.  Maybe some others you have seen have been more openly positive.  In general I think that a lot of the optimism is just the early season hope combined with what looks like a pretty decent pattern for a week coming up.  Sort of like how excited a bad football team's fans can be after they win the first game; they imagine themselves in the super bowl.  

[cbmclean]

6 minutes ago, psuhoffman said:

It's a good enso/solar analog, but not in any of the other metrics I looked at.  But that is why I am asking this...maybe I am weighting things people think don't actually matter.  

For one thing 2013 - 14 wasn't in the depths of the pit of -PDO despair that we are currently.  I think that that takes anything remotely like 2013-14 completely off the table, even in weakened form.  But then again as others have noted 2013-14 was highly anomalous to start with. 

[clskinsfan]

GFS and Euro are pretty damn close to each other at a 9 day lead. Details to be worked out obviously. 

[winter_warlock]

30 minutes ago, clskinsfan said:

GFS and Euro are pretty damn close to each other at a 9 day lead. Details to be worked out obviously. 

Well it's been a long time since we all had something like this to track... in November!!! 

[psuhoffman]

1 hour ago, WxUSAF said:

@psuhoffman, yeah not sure. My limited understanding is that QBO phase supports or detracts from high latitude blocking frequency. Webb, at least, is clearly NOT expecting a weak strat PV and strongly -AO. Quite the opposite. So not sure how QBO would make that even worse?

My thinking on that...but I am totally open to discussion and being convinced maybe it's just a fluke...but perhaps 2022 was slightly snowier here than 2009 and 2013 because when the pattern was "favorable" the TPV was slightly more displaced in 2022 than the +QBO years like 2009...(or years where the QBO was flipping positive like 2013).  But the truth is even if we go back to 1950 and include every similar enso year that happened during a deeply -PDO,  years like 1951, 1955, 1972, 2002, 2012, 2021, 2023.... NONE of them was snowy.  Not a single one was above avg snowfall at BWI!  NONE

So really the only hope we have here is that the buzz around 2014 is correct.  But that year was totally eliminated for me because we were in a pdo phase change that year...by fall the PDO was down to near -1 and by January it was near neutral and by spring we had entered a prolonged positive PDO phase.  So since my number one criteria was to only use analogs in a similarly god awful PDO phase...that year is not even an option in my analogs. 

Maybe that was a mistake?  Or maybe the PDO goes through one of the fastest phase flips ever and somehow goes from -3.5 in the fall to near neutral by winter...but I ranked that possibility very low.  But again...I'm open to being convinced that decision was a mistake.  There seems to be a lot of buzz to that effect lately.  

 

[psuhoffman]

26 minutes ago, cbmclean said:

For one thing 2013 - 14 wasn't in the depths of the pit of -PDO despair that we are currently.  I think that that takes anything remotely like 2013-14 completely off the table, even in weakened form.  But then again as others have noted 2013-14 was highly anomalous to start with. 

This was exactly my thinking 

[WxUSAF]

That’s a really cold GEFS run. BN from next Wednesday through the end of the run. 

[yoda]

Borrowed from SNE thread re 12z EPS h/t to @ORH_wxman

4 minutes ago, ORH_wxman said:

D8-9 EPS is definitely favorable on the synoptics....this isn't a deep full-wavelength event, but it's pretty classic for an early season redeveloper....note the relatively shallow shortwave over the center of the country and you have west-based -NAO weakness and a strong 50/50 sig. You'll need all of those this early in the season to hold the high in place otherwise you just won't be able to overcome the antecedent warmth offshore this early. What we don't have a stout western ridge, which is why this probably would come in at a bit of a shallow angle....so you'll need that confluence.

But at least the synoptics are there. We'll see if it still holds in another few days.

 

 

 

[soadforecasterx]

@psuhoffman  i forget where the link went but i believe PDO is down to -2 now. Yes i know not near 0 but definitely way down from -3.5. 

[brooklynwx99]

41 minutes ago, psuhoffman said:

This was exactly my thinking 

at some point, to change the -PDO, there is often a year that has a disconnect and features a +PNA... 2013-14 was that year, and the -PDO is probably going to end up close to neutral if the advertised pattern comes to fruition

not to say we're going to get a 2013-14 type year... something like a 2013/2021 mix is likely the colder scenario for the winter

[brooklynwx99]

the PDO isn't really a pattern driver... more of a pattern reinforcer. a -PDO will enhance a -PNA, but the 500mb pattern ultimately drives the SST anomalies, not the other way around

[Daniel Boone]

8 minutes ago, brooklynwx99 said:

the PDO isn't really a pattern driver... more of a pattern reinforcer. a -PDO will enhance a -PNA, but the 500mb pattern ultimately drives the SST anomalies, not the other way around

Yeah. The rapid cooling of SST'S south of Newfoundland and around Nova Scotia a case in point. 

[psuhoffman]

36 minutes ago, brooklynwx99 said:

at some point, to change the -PDO, there is often a year that has a disconnect and features a +PNA... 2013-14 was that year, and the -PDO is probably going to end up close to neutral if the advertised pattern comes to fruition

not to say we're going to get a 2013-14 type year... something like a 2013/2021 mix is likely the colder scenario for the winter

I totally agree, but both of those winters were awful in DC/Baltimore and featured much below normal snowfall, in line with my thinking.  They were both in my analog set.  That is the thing...I think people just a little north of us don't realize that you can play around with all the details, and they matter for places just to our north...there is a HUGE gradient in nina snowfall just north of us...and somethings south enough to barely save me like 2021 where I got 50" and DC got single digits!  But for DC/Baltimore...other than 2014 all these analog years were awful.  Even the colder ones, the snow was north of us.  

[psuhoffman]

@brooklynwx99I hear and respect all these arguments... and I really hope they are right.  I did say the one weakness of my new methodology was years where the PDO phase flipped unexpectedly going into a winter...those years showed significantly less predictability with my method using backwards verification tests.  So if this year is indeed an example of a PDO phase flip then I could very well be very wrong.  

[brooklynwx99]

1 minute ago, psuhoffman said:

@brooklynwx99I hear and respect all these arguments... and I really hope they are right.  I did say the one weakness of my new methodology was years where the PDO phase flipped unexpectedly going into a winter...those years showed significantly less predictability with my method using backwards verification tests.  So if this year is indeed an example of a PDO phase flip then I could very well be very wrong.  

I wasn't expecting a cold or snowy winter going into autumn with the -3.5 PDO either, believe me. however, 2013-14 has always been an intriguing year, and often times the late Nov-early Dec pattern will show the flavor of the winter, whether good or bad

[soadforecasterx]

found it 

[mattie g]

45 minutes ago, psuhoffman said:

I totally agree, but both of those winters were awful in DC/Baltimore and featured much below normal snowfall, in line with my thinking.  They were both in my analog set.  That is the thing...I think people just a little north of us don't realize that you can play around with all the details, and they matter for places just to our north...there is a HUGE gradient in nina snowfall just north of us...and somethings south enough to barely save me like 2021 where I got 50" and DC got single digits!  But for DC/Baltimore...other than 2014 all these analog years were awful.  Even the colder ones, the snow was north of us.  

2013-2014 was well above normal snowfall in DC/Baltimore.

[psuhoffman]

37 minutes ago, brooklynwx99 said:

I wasn't expecting a cold or snowy winter going into autumn with the -3.5 PDO either, believe me. however, 2013-14 has always been an intriguing year, and often times the late Nov-early Dec pattern will show the flavor of the winter, whether good or bad

Sometimes, but 2008 had almost the same pattern from Nov 15-Dec 10 and 2008-09 was a god awful snowfall year.  I think 2012-13 which was my top analog was similar...and another year with single digit snowfall across our area and less than 5" in DC.  

Was 2014 really indicative of the drivers being good that winter or just a fluke?  I can't find any other examples going back to 1950 of a weak cold enso or cold neutral +QBO winter coming off a -PDO that ended up snowy around here.  Not a single one.  All the other comps, 1951, 1955, 1972, 1975, 2002, 2009, 2012, 2013, 2021, 2022, 2023 were below average snowfall here.  That is a big enough sample size to wonder if 2014 was just a fluke where even if the same major factors repeated again and again its unlikely to result in the same output and it was due to some combination of discreet variables we can't accurately factor in currently that lead to that...or just a lot of luck with several synoptic systems.  That can happen...maybe we just hit the lottery in terms of lucking out synoptically.  Because even the examples of similar cold winters with those parameters or even smaller scale periods within winters....didn't prodice nearly as much snowfall here.  They did to our north...and they were generally cold patterns...but usually the baroclinic zone for storms ended up just to our north....or the patters were dry with systems redeveloping just north of us and hitting Philly northeast.  It makes it hard for me to use 2014, it was not the typical way we get a snowy winter down here.  

[psuhoffman]

4 minutes ago, mattie g said:

2013-2014 was well above normal snowfall in DC/Baltimore.

yes, I said EVERY OTHER analog year except 2014 was a horrible snowfall winter... read my last post to brooklyn...I think 2014 might have just been a fluke of luck or due to a combination of variables we dont yet know how to factor, because none of the other similar years going all the way back to 1950 produced anything close to that result for us.  Even the other analogs that were cold and snowy just to our north like 2001, 2009, 2013 and 2021 were low snowfall here.