Fall 2026 Medium/Long Range Pattern Thread

[nrgjeff]

Chart is on the previous page. Strato warming is more likely to dump on Europe. I truly hope I'm wrong for the sake of Ukraine. Anyway SSWs typically impact Europe first. Esp now we also got a Scandinavia block. 

I'd love to be wrong. Maybe instead of a true PV split it'll just jostle and reflect for North America. If Europe first, and warm Eastern USA, I'll take severe wx thanks. We need the rain. Hope to see y'all in the severe thread soon!

[Carvers Gap]

Some growing potential for a strong slp or cut-off just after mid-month.  Both the 12z Euro and GFS have it.  I doubt it is snow for the lower elevations, but I generally track anything that remotely looks like that.  Right now, winter is in the West.  Mammoth got 9-14" of snow at the  Main Lodge this past weekend.  They should meet their normal ski slope opener date (just a few days away).  LR ext modeling does hint that winter begins right after Thanksgiving in the East - huge grains of salt(and I mean huge).

[Carvers Gap]

The strat split stuff interests me a little bit at this time of year.  As Jeff noted, Eurasia is the primary first stop for that cold dump.  However, I think maybe it was '14-15(or '09-10 or both??? @John1122) where an early strat split set the stage for a cold second half of winter.  We will see.  I tend to be in the camp that believes that warm falls tend to flip cold very quickly during the latter half of November.  I may have to change my Dec forecast.  We will see.

[Golf757075]

32 minutes ago, Carvers Gap said:

The strat split stuff interests me a little bit at this time of year.  As Jeff noted, Eurasia is the primary first stop for that cold dump.  However, I think maybe it was 14-15 where an early strat split set the stage for a cold second half of winter.  We will see.  I tend to be in the camp that believes that warm falls tend to flip cold very quickly during the latter half of November.  I may have to change my Dec forecast.  We will see.

SSW are tricky. Been hearing alot about it, especially since its so early in season.  Not sure the benefits of it happening now if it did since its nov 2nd. Maybe higher elevations? Makes a difference. I am hopeful we can have one winter storm for us this winter.

[jaxjagman]

Tomer did some upgrades on POLAR WX,thought i already posted it

'https://www.polarwx.com/products/

[Carvers Gap]

40 minutes ago, Golf757075 said:

SSW are tricky. Been hearing alot about it, especially since its so early in season.  Not sure the benefits of it happening now if it did since its nov 2nd. Maybe higher elevations? Makes a difference. I am hopeful we can have one winter storm for us this winter.

Yes.  They are incredibly tricky.  There is a smaller cluster of solutions(over the years) which can hit NA first.  "Usually" (in my experience) those occur from late December to especially Feb - March. Now, early strat splits can do some funky stuff.   If all of that cold dumps into Asia, then it would take time for it to recharge(meaning prolonged AN temps in NA).  Like Jeff said, we really want it to get more jostled than split.  I am seeing some colder temps(at times) on LR ext models, especially some(not all) control runs.  That could be a false alarm.  We have definitely seen models jump on colder solutions for NA during SSWs and be woefully wrong.  I tend to think winter will be more of a "second half of winter" deal this year, but...a strat split could upend almost any seasonal forecast right off the bat.

[Carvers Gap]

Also, and one can see this on the Weeklies today (ensemble and control), that often SSWs(which eventually find NA) will dump directly into Montana and then race into northern Texas....and then crawl eastward.  That sets up the mid-section of the country for snow/ice for late November and early December if true.  And that also sets us up for severe per Jeff.

[Carvers Gap]

These are the 30d looks for Nov 18-Dec18.  Notice how the cold in western/central Europe teleconnects somewhat to a trough over the East of NA.  Notice on the control how the cold dumps into Texas which is not unprecedented.  Remember the '93 Thanksgiving game between Miami and Dallas(touched FG attempt) w/ ice snow.  That control run is a NASTY look for all kinds of mischief over the SE.  In NO WAY am I calling for that at this point.  I have been watching this for several days(maybe a week).  I tend to think Jeff's comments would be wise to listen to and would temper expectations at this point.  But that is a wild look on the Weeklies today.  I wouldn't say that is bitterly cold.  That Hudson Bay block has been a warm look over the past few years, but a southern storm track to accompany that.  

In short, good storm track but cold source lacking.  Honestly, that isn't a terrible look for the Southeast.   That cutoff around the Nov 17th time frame could be the first buckle in the jet which ushers in big changes over NA.  We will see.

 

 

[Carvers Gap]

On the plus side, I do think these summer time temps are gone after this week until next season.  I had hopes that extended summer was not going to prevail this year, but it certainly did!!!!

The SSW could certainly delay the typical winter analog pattern(El Nino) from taking over.  If the El Nino crashes mid-winter, then I would say, "Buckle up."  Chaos might be inbound, but we will see.  FWIW, chaos can be good or bad.

[Carvers Gap]

The last in a flurry of posts.  There is some continuity(over particularly NA) between the EURO LR Ext and the 12z CFS 30d maps for mid Nov to mid Dec....western and central Europe are obviously different.

[John1122]

I believe the strat split late November 2009. That and 1968 are two of the earliest warmings on record before this one. In 1968 we had some decent early December cold, and a deep freeze shot by mid-December with highs in the 20s and lows in the single digits. There was an additional cold shot for Christmas and then it was extremely cold in early January 1969. A nice snow event and sub zero cold. Temperatures stayed well bn through mid-January. 

[jaxjagman]

4 hours ago, John1122 said:

I believe the strat split late November 2009. That and 1968 are two of the earliest warmings on record before this one. In 1968 we had some decent early December cold, and a deep freeze shot by mid-December with highs in the 20s and lows in the single digits. There was an additional cold shot for Christmas and then it was extremely cold in early January 1969. A nice snow event and sub zero cold. Temperatures stayed well bn through mid-January. 

PolarWx has a history  going back to 1958-59

https://www.polarwx.com/strat/#history

[Carvers Gap]

A couple of early morning thought....I am just gonna place a bunch of Nov/winter stuff here.  The strat split is probably Nov discussion.  So, I am going to file the information here so that it will be easier to find later.

1.  Modeling is probably gonna be a mess with a potential disturbance of the strat.  If it actually splits, modeling could miss badly on anything depicted after the split.  I have seen models show crazy cold over NE TN w/ an SSW predicted at range....only to send it into the West at the last minute.  I have also seen models miss the cold.

2.  Early stat splits(if it actually splits...what is the timeline on it splitting?) do have some interesting analogs which might prove to be useful too our area.  Those were noted above by John.

3.  The CANSIPS has been locked into a cold winter for months.  However, it flipped November to warm(on this latestt run) after being cold.  Really, the most useful CANSIPS(for winter) is the one which is released on Dec 1.  It generally is a warm model, so colder solutions are interesting.   It also badly missed October.  It called for cold, and October was anything but that.  Now, I don't necessarily fault a model for busting with shoulder season months.  But....its recent track record might be categorized as "abysmal."  I am pretty sure it has missed August, September, and October badly.  Short story, it seems to be only correcting at the last minute, if at all.  It has been a while since it has been correct during the past few months, but it does have a history of some skill during winter.  Right now, buyer beware.  Let's see what Euro seasonals show.

4.  I think modeling is likely correct w/ BN heights over the SE for the second half of winter. I suspect the CANSIPS is over-doing how cold it will be.  Ninos have nasty habit of being cloudy, rainy, and just not quite cold enough for snow. That said, the early strat "could" really shake up even the best of LR models.  IMHO, and early strat split(IF it actually happens) reshuffles the deck for winter.  Ninos often produced big snowstorms, but only a few...with the exceptions being notable winters.  

5.  Since this is the November thread, I do think we see a very, very slow step down back to normal by the end of the month.  There is still a pretty big storm showing up around the last third of the month.  It looks like it lacks a cold air source, but higher elevations might want to watch it.  The 0z Euro phased the thing w/ northern jet energy(SE of the benchmark?).  Modeling, when it picks up big storms like that at range, is often onto something.  Looks like a rainer, but could be a strong slp or even a bowling ball low.  Something interesting to watch.  There is a legit chance for a big flip to cold later during November as warm falls often are followed by that.

6.  As several have noted, we need the rain.  It has been feast or famine this year w/ rainfall.  NE TN generally finds a way "not to rain" at this time of year.  

7.  Does this El Nino suddenly crash?  There are some signals that it might.  If so, winter could begin w/ a strong Nino, progress to a weak Nino by the last third of winter, and then descend to neutral by early spring.  That would leave a window(and Cosgrove has noted this) for cold and stormy weather during the last half of winter.

8.  Of note, the nights have been chilly w/ low humidity ongoing.  As soon as the sun goes down, the tempt plummets IMBY.

[Carvers Gap]

One last note, we need to watch the GFS for cold fronts at this time of year.  In the past, it generally has performed the best during November and December when sniffing out cold fronts.  The Euro usually is better after mid-Dec and through Feb.  I don't see much on the GFS(yet) indicating any flip to cold.  Right now, it just shows normal cold fronts pushing into warmer air masses.  But watch it carefully for the end of the month and earl Dec....it will likely catch any potential shenanigans first.

[*Flash*]

3 hours ago, Carvers Gap said:

A couple of early morning thought....I am just gonna place a bunch of Nov/winter stuff here.  The strat split is probably Nov discussion.  So, I am going to file the information here so that it will be easier to find later.

1.  Modeling is probably gonna be a mess with a potential disturbance of the strat.  If it actually splits, modeling could miss badly on anything depicted after the split.  I have seen models show crazy cold over NE TN w/ an SSW predicted at range....only to send it into the West at the last minute.  I have also seen models miss the cold.

2.  Early stat splits(if it actually splits...what is the timeline on it splitting?) do have some interesting analogs which might prove to be useful too our area.  Those were noted above by John.

3.  The CANSIPS has been locked into a cold winter for months.  However, it flipped November to warm(on this latestt run) after being cold.  Really, the most useful CANSIPS(for winter) is the one which is released on Dec 1.  It generally is a warm model, so colder solutions are interesting.   It also badly missed October.  It called for cold, and October was anything but that.  Now, I don't necessarily fault a model for busting with shoulder season months.  But....its recent track record might be categorized as "abysmal."  I am pretty sure it has missed August, September, and October badly.  Short story, it seems to be only correcting at the last minute, if at all.  It has been a while since it has been correct during the past few months, but it does have a history of some skill during winter.  Right now, buyer beware.  Let's see what Euro seasonals show.

4.  I think modeling is likely correct w/ BN heights over the SE for the second half of winter. I suspect the CANSIPS is over-doing how cold it will be.  Ninos have nasty habit of being cloudy, rainy, and just not quite cold enough for snow. That said, the early strat "could" really shake up even the best of LR models.  IMHO, and early strat split(IF it actually happens) reshuffles the deck for winter.  Ninos often produced big snowstorms, but only a few...with the exceptions being notable winters.  

5.  Since this is the November thread, I do think we see a very, very slow step down back to normal by the end of the month.  There is still a pretty big storm showing up around the last third of the month.  It looks like it lacks a cold air source, but higher elevations might want to watch it.  The 0z Euro phased the thing w/ northern jet energy(SE of the benchmark?).  Modeling, when it picks up big storms like that at range, is often onto something.  Looks like a rainer, but could be a strong slp or even a bowling ball low.  Something interesting to watch.  There is a legit chance for a big flip to cold later during November as warm falls often are followed by that.

6.  As several have noted, we need the rain.  It has been feast or famine this year w/ rainfall.  NE TN generally finds a way "not to rain" at this time of year.  

7.  Does this El Nino suddenly crash?  There are some signals that it might.  If so, winter could begin w/ a strong Nino, progress to a weak Nino by the last third of winter, and then descend to neutral by early spring.  That would leave a window(and Cosgrove has noted this) for cold and stormy weather during the last half of winter.

8.  Of note, the nights have been chilly w/ low humidity ongoing.  As soon as the sun goes down, the tempt plummets IMBY.

Agreed, Carver. I think we ultimately stair-step our way toward a more favorable pattern as November progresses, potentially setting the stage for something memorable as we close out the year. No rush for winter to arrive just yet. I'd rather see the building blocks fall into place heading into December.