2025-2026 ENSO

[FPizz]

23 minutes ago, GaWx said:

Yesterday’s Euro: phase 8 starts 12/14:

 

Today’s Euro: phase 8 starts 10 days earlier, 12/4, (with a 6+day long phase 8 implied) although I’d want to make sure it isn’t curling back into 7 and staying there:

Is the ext available to compare the same outputs?  Maybe instead of doing the loop in phase 7, it does it right on the line between 7/8 then goes back into 8.  Yesterdays did the loop in 7

[bluewave]

1 hour ago, 40/70 Benchmark said:

Yes, I def. wouldn't love this in your area.

Yea, difference should be enough to get me in the game, at least. 

Mount Mansfield off to a great start.

 

[PhiEaglesfan712]

20 minutes ago, SnowGoose69 said:

Not surprised to see it was during a Nino too where Dec tends to lean milder anyway.  I think we had a small snow event in SNE a few days prior to that too.  

Funny, that year behaved the opposite of a nino (due to Pinatubo). Normally, you'd get the cool summer in the East preceding the el nino and the warm summer in the East following the el nino. Instead, the summer of 91 was a record warm summer in the East, and the summer of 92 was the cold summer in the East.

Of course, Pinatubo resulted in a temporary cooling, which led the snowier winters of 92-93, 93-94, and maybe even 95-96.

[GaWx]

24 minutes ago, FPizz said:

Is the ext available to compare the same outputs?  Maybe instead of doing the loop in phase 7, it does it right on the line between 7/8 then goes back into 8.  Yesterdays did the loop in 7

1. No, ext for same run comes out a day later.

——————

2. GEFS 2 days ago:

GEFS yesterday: gets to phase 8 five days earlier than any other GEFS as of then:

 

GEFS today: curled back very slightly vs yesterday (E US cold lovers wouldn’t want a curl back into phase 7) but very similar to yesterday/look how different it is vs 2 days ago!

[snowman19]

@40/70 Benchmark @Donsutherland1 @Bluewave

They are finally admitting the obvious…
 

 

“A stratospheric wave-reflection event is becoming more likely. Energy that had been expected to propagate into the stratosphere and weaken the vortex now appears more likely to reflect back into the troposphere.

This often strengthens the Atlantic jet stream and can trigger a rapid recovery in the stratospheric vortex. This is likely why recent modelling has shifted toward a more zonal pattern compared with earlier expectations.

If this occurs, and we see downward coupling from the stratosphere into the troposphere during December, then even with supportive background signals for blocking, stronger westerlies aloft could flatten the pattern and favour a more zonal setup significantly reducing the risk of sustained blocking or cold.”

 

[bluewave]

20 minutes ago, snowman19 said:

@40/70 Benchmark @Donsutherland1 @Bluewave

They are finally admitting the obvious…
 

 

“A stratospheric wave-reflection event is becoming more likely. Energy that had been expected to propagate into the stratosphere and weaken the vortex now appears more likely to reflect back into the troposphere.

This often strengthens the Atlantic jet stream and can trigger a rapid recovery in the stratospheric vortex. This is likely why recent modelling has shifted toward a more zonal pattern compared with earlier expectations.

If this occurs, and we see downward coupling from the stratosphere into the troposphere during December, then even with supportive background signals for blocking, stronger westerlies aloft could flatten the pattern and favour a more zonal setup significantly reducing the risk of sustained blocking or cold.”

 

December has been one of the most challenging months for sustaining deep -NAO patterns since 2011. Pretty much the opposite of May. This is one of the reasons why we haven’t seen a repeat of record December snows from 2000 to 2010 around NYC. 

[anthonymm]

I like how we all gave MJO812 weenie emojis for saying everyone overestimating SE ridge and he was completely validated. I will admit I have a warm bias. Maybe some others should step up and admit it too. 

[TheClimateChanger]

1 hour ago, donsutherland1 said:

This is pretty much the consensus idea for the first 10 days of December. The cold will spread through the Upper Midwest, the Great Lakes and then eastward. Some pieces could reach the Southeast as the ridge is flattened for a time. Unfortunately, if the latest guidance is right, like a champion fighter, the SE Ridge will pick itself up and keep coming back. Then, if some of the more recent guidance is right, namely the development of an AO+ pattern, the ridge could rebuild. The Great Lakes Area (Chicago, Detroit, Milwaukee, Toronto) and northern New England/eastern Canada should see a continuation of the cold past mid-December and perhaps onward. 

I suspect that snow will develop in the Chicago area late Saturday or Saturday night and then spread into Detroit and Toronto afterward. A moderate snowfall appears likely.

Thanks for the update, Don. This looks similar to the wintertime pattern I got when I ran the warmest CONUS Novembers forward, with cold in the Upper Midwest and Pacific Northwest. Warm south and east, with a stout SE Ridge. Hoping the ridge is underestimated a bit and milder air is able to infiltrate the Great Lakes region as well as we head into mid December.

[TheClimateChanger]

9 minutes ago, anthonymm said:

I like how we all gave MJO812 weenie emojis for saying everyone overestimating SE ridge and he was completely validated. I will admit I have a warm bias. Maybe some others should step up and admit it too. 

Could be a case of delayed, but not denied, as JB often says. I wouldn't throw in the towel just yet. Suspect we'll see some more SE ridge mischief as we head into the month of December.

[MJO812]

Once the MJO gets to phase 8 , it kills the southeast ridge and then the the polar vortex presses in. The coldest part of December is likely from the 15th to the 25th.

 

[40/70 Benchmark]

27 minutes ago, anthonymm said:

I like how we all gave MJO812 weenie emojis for saying everyone overestimating SE ridge and he was completely validated. I will admit I have a warm bias. Maybe some others should step up and admit it too. 

I think a bias requires an actual forecast. I would admit that you you use reverse psychology as a defense mechanism if I were you.

[TheClimateChanger]

1 hour ago, MJO812 said:

MJO moving along

Great sign

Interesting. At least at looks to be moving through at a pretty good clip, so might just be a temporary excursion in Phase 8.

[LakePaste25]

1 hour ago, anthonymm said:

I like how we all gave MJO812 weenie emojis for saying everyone overestimating SE ridge and he was completely validated. I will admit I have a warm bias. Maybe some others should step up and admit it too. 

Fair but we also don’t verify a forecast with a forecast. 

[bluewave]

9 minutes ago, LakePaste25 said:

Fair but we also don’t verify a forecast with a forecast. 

Plus we are talking about the long term increasing influence of the Southeast or Western Atlantic ridge on our sensible weather.

 

[LakePaste25]

Just now, bluewave said:

Plus we are talking about the long term increasing influence of the Southeast ridge.

 

Yeah, there’s no doubt that the warming climate is increasing the size of the SE ridge regardless of whether it gets over or under modeled. Ridges are getting larger and the breadth of below normal temps from troughs is getting smaller. These are just facts.

doesn’t mean it can’t snow or get cold though. But in terms of getting the colder temps, it’s like spinning a prize wheel with less winning spaces to land on. 

[michsnowfreak]

2 hours ago, TheClimateChanger said:

Thanks for the update, Don. This looks similar to the wintertime pattern I got when I ran the warmest CONUS Novembers forward, with cold in the Upper Midwest and Pacific Northwest. Warm south and east, with a stout SE Ridge. Hoping the ridge is underestimated a bit and milder air is able to infiltrate the Great Lakes region as well as we head into mid December.

The orientation of temp departures this November is absolutely nothing like the top 3 warmest novembers. DTW finished in the top 20 warmest in the top 3 warmest conus Novembers, and will finish this November colder than avg.

[GaWx]

51 minutes ago, TheClimateChanger said:

Interesting. At least at looks to be moving through at a pretty good clip, so might just be a temporary excursion in Phase 8.

That ext Euro phase 8 lasts 11 days, which would be the longest in Dec since 1975. I just hope it actually gets there and stays for awhile rather than curl back to 7 to stay.

[snowman19]

13 minutes ago, bluewave said:

Plus we are talking about the long term increasing influence of the Southeast or Western Atlantic ridge on our sensible weather.

 

A big part of the problem nowadays is flooding the general public with unrealistic expectations, then when it fails, they lose all trust in the “weathermen”. We have pro mets (no not on here) blindly hyping “MJO phase 8!!!”, speaking in declaratives without any context like it’s always a guaranteed magical light switch and using/hyping extreme analogs like December, 1983, December 1989 and December, 2010, telling people that it’s going to be a redux. When the public sees that and it ends up failing, they lose trust in the profession 

[bluewave]

24 minutes ago, LakePaste25 said:

Yeah, there’s no doubt that the warming climate is increasing the size of the SE ridge regardless of whether it gets over or under modeled. Ridges are getting larger and the breadth of below normal temps from troughs is getting smaller. These are just facts.

doesn’t mean it can’t snow or get cold though. But in terms of getting the colder temps, it’s like spinning a prize wheel with less winning spaces to land on. 

Even with a very strong -EPO +PNA this fall on the storm days, the Western Atlantic ridge found a way to flex. The composite below is for the 11 wettest days of fall in NYC. The main storm track was still through the Eastern Great Lakes. 

 

[MJO812]

2 minutes ago, snowman19 said:

A big part of the problem nowadays is flooding the general public with unrealistic expectations, then when it fails, they lose all trust in the “weathermen”. We have pro mets (no not on here) blindly hyping “MJO phase 8!!!”, speaking in declaratives without any context like it’s always a guaranteed magical light switch and using/hyping extreme analogs like December, 1983, December 1989 and December, 2010, telling people that it’s going to be a redux. When the public sees that and it ends up failing, they lose trust in the profession 

Who ?

[MJO812]

Warmth vanished on the gfs 

[George001]

6 minutes ago, snowman19 said:

A big part of the problem nowadays is flooding the general public with unrealistic expectations, then when it fails, they lose all trust in the “weathermen”. We have pro mets (no not on here) blindly hyping “MJO phase 8!!!”, speaking in declaratives without any context like it’s always a guaranteed magical light switch and using/hyping extreme analogs like December, 1983, December 1989 and December, 2010, telling people that it’s going to be a redux. When the public sees that and it ends up failing, they lose trust in the profession 

The modeled pattern now looks more like Dec 07 or Dec 08 than Dec 2010. Still great for northern areas, more dicey SE due to the lack of blocking. @40/70 Benchmark appears to have had the right idea based on recent changes to the long range guidance.

[PhiEaglesfan712]

35 minutes ago, snowman19 said:

A big part of the problem nowadays is flooding the general public with unrealistic expectations, then when it fails, they lose all trust in the “weathermen”. We have pro mets (no not on here) blindly hyping “MJO phase 8!!!”, speaking in declaratives without any context like it’s always a guaranteed magical light switch and using/hyping extreme analogs like December, 1983, December 1989 and December, 2010, telling people that it’s going to be a redux. When the public sees that and it ends up failing, they lose trust in the profession 

December 2010 is the only one that's reasonable. At least that happened in the newer climate. (It's not a good analog, but due to other things... like near solar min and strong la nina, features we don't have this year. Maybe it could work if we have a strong la nina in place in December 2028, when we're closer to a solar min.)

December 1983 is an older, colder climate. Not likely to happen unless we have a Pinatubo event. (83-84 actually would have been a very good analog for 95-96.)

December 1989, well, that was a once-in-a-lifetime event. A coldest December on record, followed by an early turn to spring (and never looking back) is almost certainly never going to happen again.

[GaWx]

4 hours ago, GaWx said:

The colder trend for early Dec is happening on all ensembles including GEFS: these are all for a week from today at 7PM: watch the SER disappear:
 

 

@donsutherland1@bluewave

 The above noted colder GEFS trend for early Dec continued with the 12Z run.

[Cobalt]

On 11/15/2025 at 10:59 AM, qg_omega said:

Looks very warm in the East starting Thanksgiving week

An excellent call once again

[40/70 Benchmark]

1 hour ago, George001 said:

The modeled pattern now looks more like Dec 07 or Dec 08 than Dec 2010. Still great for northern areas, more dicey SE due to the lack of blocking. @40/70 Benchmark appears to have had the right idea based on recent changes to the long range guidance.

We are going to get some Arctic High regime (-NAO), but its just gone by mid month....AWT.

[40/70 Benchmark]

My area's best Decembers are the SWFE patterns...a la 1970, 2007, 2008....big coastals this time of year usually produce a lot of mush on the CP.

[Terpeast]

2 hours ago, MJO812 said:

Once the MJO gets to phase 8 , it kills the southeast ridge and then the the polar vortex presses in. The coldest part of December is likely from the 15th to the 25th.

 

I think it might be later than that, if we even see sustained phase 8. 

[MJO812]

1 minute ago, Terpeast said:

I think it might be later than that, if we even see sustained phase 8. 

Quite possible with the lag

[MJO812]

46 minutes ago, Cobalt said:

An excellent call once again

Euro is now colder in the long range . All the models have trended colder. 

Euro is frigid