2025-2026 ENSO

[bluewave]

13 hours ago, EasternLI said:

 

Nice post man. You know that I agree with this assessment. We've had some good chats about this occasionally in past years. It's a real factor and should be considered into the equation. Having said that. I don't think we should rush to judgement yet on this particular MJO event and I'll try to explain why. This event thus far has been driven to propagate eastward with CCKW's. Which operate due to different circumstances from the MJO and with much faster timescales. Since the beginning of this event really, they've been noticeable in the data and the models. I mentioned this phenomenon in a post here last month I think too. This is still the case on current runs. We've been seeing this alternating constructive and destructive interference cycling through the event as they do. Which is presenting itself as the loops around on the RMM charts we've been seeing. It was slowed, naturally, as it approached the La Nina state in addition to that as well. However, it seems to want to persevere on the longer range guidance. Regular ensemble runs (gefs/eps) don't run out far enough to capture the whole picture. What we've been seeing with those is an amplified trend when there is constructive interference. Mixed with other times where the signal almost vanishes when there is destructive interference from these CCKW's. The latest one is about to constructively interfere, which is offering some boost to the Phase 7 signal upcoming. Some here seem to be under the impression that the phase 8 attempt is within range of the current medium range ensembles. I think that is a mistake. Any signal giving that impression should be the current CCKW continuing to propagate through to the east. So what I think will happen, is that we will see the amplification into phase 7 as guidance is advertising. Followed by a degradation which will be denoted once again with the RMM chart doing a loop with the signal again. IMO the actual attempt for the push into phase 8 comes a little after that. With the next CCKW that should propagate through and is modeled to do so. If guidance is any indication, that should occur close to mid month in December IMO. Outside of the range of current gefs/eps runs. We'll probably see a more ambiguous signal until that time. Much like the later stages of the 12z GEFS posted right below. It could in fact fail and possibly for the reasoning that you've laid out very nicely here. Personally I think the jury is still out for this one, but that they will enter the building around mid December to prepare the verdict. Such as euro (and gefs for that matter) weekly data suggests. Today's euro weekly forecast at the very bottom. 

 

 

Today's Euro weeklies VP200 followed by U850:

Thanks for the kind words. I really enjoy our discussions over the years. My guess is that  the reason for both the CCKW and MJO activity following the pattern we have been describing is the extensive +28 to +30C warm pool near the 6-7 zones on the chart that you posted.

So this has been causing the looping activity on the RMM charts that we have been frequently observing over recent years. The CCKW and MJO interaction could also be why we are seeing these stronger Southeast ridge patterns than just using a straight MJO 7 composite. I was hinting at this in our recent conversation on the MJO 7 composites.

Perhaps these composites lose some effectiveness since the sample size of events is smaller and merged with the CCKW interactions which has been more recent as the WPAC warm pool has been expanding.  So when the forcing stalls closer to the 6-7 regions, it delays the passage into Phase 8 like we have seen so often since February 2022.

Plus the continuing 6-7 area convection interferes with the typical MJO 8 composites like last January when the Pacific Jet remained rather strong due to the lingering forcing there in concert with the very strong SST gradient over the midlatitude Pacific to the east of Japan and south of the Aleutians.

 

[40/70 Benchmark]

Problem is that today not enough people are concerned with thinking critically.... and just want to generate clicks on social media while touching themselves to red colors near the North Pole.

[snowman19]

8 minutes ago, 40/70 Benchmark said:

Problem is that today not enough people are concerned with thinking critically.... and just want to generate clicks on social media while touching themselves to red colors near the North Pole.

I don’t want to jinx you but it’s looking like a very good call on your part with the SPV, along with the increasingly likely flip to RNA/-PNA in December 

Edit: Also have to give credit to @bluewave with the -PNA December call (looks likely now)

[40/70 Benchmark]

1 minute ago, snowman19 said:

I don’t want to jinx you but it’s looking like a very good call on your part with the SPV, along with the increasingly likely flip to RNA in December 

I'm sure my forecast will go astray at some point, but I've learned so much about the strat this summer and fall.

[40/70 Benchmark]

I'm interested to see if DT starts to sweat when he releases the this week in WX video.

[snowman19]

3 minutes ago, 40/70 Benchmark said:

I'm interested to see if DT starts to sweat when he releases the this week in WX video.

Yea Ray, DT really thought December was going to be a big +PNA month….

[40/70 Benchmark]

7 minutes ago, snowman19 said:

Yea Ray, DT really thought December was going to be a big +PNA month….

TBH, I was nervous that I should have incorporated more of the December 2000 MJO behavior (phase 8) and gone colder, but I have learned to err on the side of caution with respect to that in this modern era (see Bluewave).

[bluewave]

16 minutes ago, snowman19 said:

Edit: Also have to give credit to @bluewave with the -PNA December call (looks likely now)

Several of us came to the conclusion that the PNA would be weaker than last December by using different methods which converged on the same solution.

[40/70 Benchmark]

23 minutes ago, snowman19 said:

I don’t want to jinx you but it’s looking like a very good call on your part with the SPV, along with the increasingly likely flip to RNA/-PNA in December 

Edit: Also have to give credit to @bluewave with the -PNA December call (looks likely now)

Another interesting tidbit about the modern climate that @Stormchaserchuck1has pointed out is the tendency for -NAO intervals to coincide with -PNA.....which is important considering there should be some -NAO episodes early on. I think there was also a graphic he posted concerning the negative correlation for the following December after a strongly +PNA (last year)....not to mention the GLAAM being significantly more negative than last year. This dove tailed nicely into my expectation for a rapid recovery of the PV and lead into a January reflection event triggering a mid season +TNH pattern.

[brooklynwx99]

6 minutes ago, 40/70 Benchmark said:

Another interesting tidbit about the modern climate that @Stormchaserchuck1has pointed out is the tendency for -NAO intervals to coincide with -PNA.....which is important considering there should be some -NAO episodes early on. I think there was also a graphic he posted concerning the negative correlation for the following December after a strongly +PNA (last year)....not to mention the GLAAM being significantly more negative than last year. This dove tailed nicely into my expectation for a rapid recovery of the PV and lead into a January reflection event triggering a mid season +TNH pattern.

you usually get the wave breaking needed for -NAO when you get a huge cutter... you usually need -PNA to accomplish this

[brooklynwx99]

the lack of a prolonged SPV disruption lessens the risk of blocking this month... maybe late, but who knows this far out

overall, looks pretty meh for the Northeast into mid-late month. the -WPO and TPV in Canada should continue to present snowfall risks, especially into New England, but large storms look unlikely as long as the NAO remains positive and the PNA negative

should see the PNA rise later on in the month as the MJO continues to progress 

[40/70 Benchmark]

4 minutes ago, brooklynwx99 said:

the lack of a prolonged SPV disruption lessens the risk of blocking this month... maybe late, but who knows this far out

overall, looks pretty meh for the Northeast into mid-late month. the -WPO and TPV in Canada should continue to present snowfall risks, especially into New England, but large storms look unlikely as long as the NAO remains positive and the PNA negative

should see the PNA rise later on in the month as the MJO continues to progress 

Yea, but the PV isn't stout, either....you don't need February 2010 blocking to slide just under neutral in the monthly mean (NAO). This will be a good snowfall pattern for NE, but not the mid atl...agree. No KUs, but rather a series of moderate snowfalls owed to WAA/SWFEs.

January will be the +PNA mismatch month this season....take that to the bank.

[Terpeast]

4 minutes ago, 40/70 Benchmark said:

Yea, but the PV isn't stout, either....you don't need February 2010 blocking to slide just under neutral in the monthly mean (NAO). This will be a good snowfall pattern for NE, but not the mid atl...agree. No KUs, but rather a series of moderate snowfalls owed to WAA/SWFEs.

January will be the +PNA mismatch month this season....take that to the bank.

Same page, I'm still thinking January is the cold month for the east. Best chance for MA snows before Feb torch. Dec isn't really in play for us down here imho

[40/70 Benchmark]

1 minute ago, Terpeast said:

Same page, I'm still thinking January is the cold month for the east. Best chance for MA snows before Feb torch. Dec isn't really in play for us down here imho

I don't think January will be cold in the mean because the second half cold will largely serve to negate the first half warmth. I think February and/or March will be colder.

[Stormchaserchuck1]

34 minutes ago, 40/70 Benchmark said:

Another interesting tidbit about the modern climate that @Stormchaserchuck1has pointed out is the tendency for -NAO intervals to coincide with -PNA.....which is important considering there should be some -NAO episodes early on. I think there was also a graphic he posted concerning the negative correlation for the following December after a strongly +PNA (last year)....not to mention the GLAAM being significantly more negative than last year. This dove tailed nicely into my expectation for a rapid recovery of the PV and lead into a January reflection event triggering a mid season +TNH pattern.

CPC said last Winter was the most +PNA Winter or record for a non-El Nino. Fwiw, there was a pretty -PNA period Jan 15 - Feb 10 that they were calling +PNA, but on these correlation maps what they say the index is what's used for correlations. 

I found it interesting that one year after most +PNA Winter's there isn't a +PNA signal the following Winter.. actually there is +NOI (+North Pacific High - the high pressure off the west coast), and that indicates more of a La Nina pattern... it was slightly predicting a la nina this winter. 

1 December after last Dec +PNA...

Fwiw, Jan +1 year doesn't reverse like December usually does

[MJO812]

8 minutes ago, 40/70 Benchmark said:

I don't think January will be cold in the mean because the second half cold will largely serve to negate the first half warmth. I think February and/or March will be colder.

First half warmth ? I think its will be the opposite if the MJO goes into 8 next month. 

[40/70 Benchmark]

1 minute ago, Stormchaserchuck1 said:

CPC said last Winter was the most +PNA Winter or record for a non-El Nino. Fwiw, there was a pretty -PNA period Jan 15 - Feb 10 that they were calling +PNA, but on these correlation maps what they say the index is what's played with for correlations. 

I found it interesting that one year after most +PNA Winter's there isn't a +PNA signal the following Winter.. actually there is +NOI (+North Pacific High - the high pressure off the west coast), and that indicates more of a La Nina pattern... it was slightly predicting a la nina winter. 

1 December after last Dec +PNA...

Fwiw, Jan +1 year doesn't reverse like December usually does

This is also supportive of a +PNA January.

[40/70 Benchmark]

3 minutes ago, MJO812 said:

First half warmth ? I think its will be the opposite if the MJO goes into 8 next month. 

MJO doesn't look to be much of a factor for early January, as will probably enter the COD by Xmas, so we are going to be left with a consolidating PV and PT regime.

[snowman19]

18 minutes ago, 40/70 Benchmark said:

I don't think January will be cold in the mean because the second half cold will largely serve to negate the first half warmth. I think February and/or March will be colder.

If I had to guess right now March would be the colder month if you end up being correct about a February SSWE. There would obviously be a lag (i.e. February, 2018). As of today I’m definitely on the canonical La Niña February thinking. That said, even if there is a February SSWE, I kind of doubt it would be as historic as 2018, since those are usually like a one in every 20 years event

Edit: @40/70 Benchmark Yes, I’m not saying epic torch like February, 2018. That would be ridiculous, however, a canonical Niña warmer than average February? Absolutely 

[40/70 Benchmark]

Just now, snowman19 said:

If I had to guess right now March would be the colder month if you end up being correct about the February SSWE. There would obviously be a lag (i.e. February, 2018). As of today I’m definitely on the canonical La Niña February thinking. That said, even if there is a February SSWE, i kind of doubt it would be as historic as 2018, since those are usually like a one in every 20 years event

Don't underestimate the ability of +TNH to linger into February.

Here is a list provided by Lee at al (2019) of the most prominent reflection events of the past 45 years, including the primary analogs of 2001 and 2018.

 

 

Courtesy Lee et al 2019

 

The mean length of the process is 20 days, with 10 days being the minimum, and 60 days the maximum, per Lee et al (2019). Considering the length of the 2001 (33 days) and 2018 (20) events, it as expected that a reflection event will begin between approximately January 13th and 16th 2026, and end between about February 2 and 18th. 

[40/70 Benchmark]

Just as you argue the SSW is unlikely to be as impactful, I would also argue that February is unlikely to be as warm and the reflection event will last longer. Notice that 2018 was on the shorter end of the spectrum...

[40/70 Benchmark]

Maybe a compromise??

[40/70 Benchmark]

Could also throw 2001 in.

[michsnowfreak]

36 minutes ago, 40/70 Benchmark said:

Yea, but the PV isn't stout, either....you don't need February 2010 blocking to slide just under neutral in the monthly mean (NAO). This will be a good snowfall pattern for NE, but not the mid atl...agree. No KUs, but rather a series of moderate snowfalls owed to WAA/SWFEs.

January will be the +PNA mismatch month this season....take that to the bank.

Good snowfall pattern stretching from the upper midwest and Great Lakes into new England, with poorer snow chances in the midatlantic and points south is, again, classic Nina December.

[stadiumwave]

 

FWIW, 15 day changes

[Blue Dream]

You guys need to smoke some weed

[LakePaste25]

For december, one would definitely want to be north of I-80. Even here, probably still dealing with rain from time to time. 

 

[FPizz]

50 minutes ago, michsnowfreak said:

Good snowfall pattern stretching from the upper midwest and Great Lakes into new England, with poorer snow chances in the midatlantic and points south is, again, classic Nina December.

Also pretty classic climo.  All the places mentioned is typical for this time of the year winter weather wise.  The further N you are, the better chances you have.  

[brooklynwx99]

16 minutes ago, LakePaste25 said:

For december, one would definitely want to be north of I-80. Even here, probably still dealing with rain from time to time. 

 

the TPV elongating like that into SE Canada should present opportunities for overrunning

[MJO812]

57 minutes ago, michsnowfreak said:

Good snowfall pattern stretching from the upper midwest and Great Lakes into new England, with poorer snow chances in the midatlantic and points south is, again, classic Nina December.

Classic Nina December is better for points south . It gets tougher once you get to February .