2025-2026 ENSO

[bluewave]

The record breaking Aleutian Ridge continues to warm the SSTs below leading to these persistent -PDOs again dropping back under -2.00. So the net effect is a record Southeast Ridge like we are seeing this week near 600 dm. This is what is driving such a strong La Niña background pattern. So there is probably a feedback process leading to the record warm subtropical SSTs. The RONI would be much lower if we subtracted the Nino 3.4 tropical SST departures from the subtropical. 

 

[40/70 Benchmark]

On 6/19/2025 at 4:16 PM, Stormchaserchuck1 said:

Keep in mind that October 2024 was the lowest monthly PDO on record, going back to the 1800s, so this recent dip is no lite event. June PNA has a pretty good correlation with a stronger Winter SE ridge in Dec-Jan-March. We'll be around -1 for June PNA (correlation of below maps is opposite for negative phase)

[Typhoon Tip]

2 hours ago, bluewave said:

The record breaking Aleutian Ridge continues to warm the SSTs below leading to these persistent -PDOs again dropping back under -2.00. So the net effect is a record Southeast Ridge like we are seeing this week near 600 dm. This is what is driving such a strong La Niña background pattern. So there is probably a feedback process leading to the record warm subtropical SSTs. The RONI would be much lower if we subtracted the Nino 3.4 tropical SST departures from the subtropical. 

 

 

It's call thermal memory associated with climate change ...

[bluewave]

4 minutes ago, Typhoon Tip said:

It's call thermal memory associated with climate change ...

The interesting thing is that the 500mb record heights emerged prior to any SST signal. So once the SSTs below reach a certain level a feedback process probably kicks in perpetuating the record ridge persistence even further. But it would be interesting to know which specific area of the planet warmed  past a certain threshold leading to the emergence of the ridge before the SST lagged response. My guess the initial 500mb Rossby Wave train impulse began somewhere closer to the tropics. Perhaps the Indio Pacific warm pool. But there could also be an interplay between the Atlantic and Pacific at work.

[40/70 Benchmark]

@Stormchaserchuck1..here are SSTs from Augus to November 2021, preceding the only -WPO DM since 2016-2017.

 

 

 

 

Now here is last year, which was featured a major DM +WPO...check out the difference around the Indian Ocean and even east of Japan...

[Typhoon Tip]

1 hour ago, bluewave said:

The interesting thing is that the 500mb record heights emerged prior to any SST signal. So once the SSTs below reach a certain level a feedback process probably kicks in perpetuating the record ridge persistence even further. But it would be interesting to know which specific area of the planet warmed  past a certain threshold leading to the emergence of the ridge before the SST lagged response. My guess the initial 500mb Rossby Wave train impulse began somewhere closer to the tropics. Perhaps the Indio Pacific warm pool. But there could also be an interplay between the Atlantic and Pacific at work.

it's almost like it's just sync aligning the response circuitry.

  ( like wtf does that mean?!  haha).   I mean, first the 500 mb responds.  Because it is free atmosphere, ..which physically means it would respond to a heat surplussing first.  etc... But, the ensuing circulation forcing then constructs/effects in the ocean patterns of wind-SS stressing.  The heat aggregation regions emerge. 

This may look like a positive feedback?  But technically it would just a response tapestry.  

Hard to say...  there's definitely a lot of a "emergent" properties due to the immensely complex interacting forces that are also in themselves, in a state of delta.  It's kind of a having thousands of 3-body problems, the result of each one, then resulting in a new 3-body problem ( metaphor).  What looks like cause and effect, may in fact be more synergistic - sort of where your intimating.   What I'm saying above is kind of lineary cause and effect, then casting an allusion. 

It's all conjecture.   

Part of the problem is that there really aren't discrete boundaries between these systems.  The do effect one another, while also heating differentially both among themselves, but wrt one another in a "quasi" coupled way.   The devil lurks in Quasi

Anyway, getting into the details of how/why?   good luck.   But I do suspect that thermal memory, which is coherently observed in Quantum Mechanics and nature and ...basically reality, plays a role there. 

And I don't disagree with the notion that heat dispersion mechanics out of the tropics plays a role in wave mechanics at mid latitudes.   

[so_whats_happening]

It is just gross outside 93/76 should hit 98 today and 99 tomorrow.

 

[Stormchaserchuck1]

22 hours ago, 40/70 Benchmark said:

Agreed......I am going to use your SST WPO correlation this year. I took my first stab at the WPO last year and missed it.

Correlation actually hits a little different at different times of the year.. there is a Spring/early Summer correlation and a Fall correlation. 

Counter-intuitively, there is a +PDO correlation in the Apr-Jul composite before a +WPO Winter. I know the last 8 years have had mostly -PDO with +WPO, but if you go over a longer dataset (to 1948, 73 years), there is actually a +PDO signal in the Spring

^The global pattern as you can see early in the year is still south. 

That pattern really lifts north by the Fall, and gives us these high correlations over the Indian Ocean and ENSO the Fall before. That +0.6 correlation max SE of India is ridiculous for a 73 year dataset (very high).  

[Stormchaserchuck1]

14 hours ago, 40/70 Benchmark said:

[Dec 2021 US Temps]

Dec 2021 actually had an all time record breaking Aleutian ridge.. it reached +600 for a couple of days at its max! I know 21-22 is the only -WPO Winter since 16-17, but the -PNA was more powerful that Winter. The Aleutian ridge just went poleward. 

[Stormchaserchuck1]

11 hours ago, 40/70 Benchmark said:

@Stormchaserchuck1..here are SSTs from Augus to November 2021, preceding the only -WPO DM since 2016-2017.

Now here is last year, which was featured a major DM +WPO...check out the difference around the Indian Ocean and even east of Japan...

La Nina is also somewhat of a -WPO indicator.. Indian Ocean didn't look like it had strong SSTA's that year. I would look at the map and say slightly negative projection. 

[Stormchaserchuck1]

June will be the 5th month in a row with +NAO

4th straight month of +AO

4th straight month of -PNA

Quite a streak for bad indexes if it were Winter lol

[Stormchaserchuck1]

The wet pattern just continues and continues

Since 2002, every "developing drought" has been followed by well above average rainfall in the eastern 1/2 of the US. 

[so_whats_happening]

2 hours ago, Stormchaserchuck1 said:

The wet pattern just continues and continues

Since 2002, every "developing drought" has been followed by well above average rainfall in the eastern 1/2 of the US. 

Since the water year we are still about 4-7" below average. It has only been May that has shown to be above average thus far, decently so at that. April was close but it stuck right along the 95 corridor that managed slightly above average around philly. June has been a bit of a struggle but we need the thunderstorms as we close out the month to produce about 1.5" across the area (PA and northern MD) then we should hit average and maybe slightly above but we have a ways to go before we can say the drought has been knocked out. If we manage near average the next few months we still end up below average for the water year only a tropical system will bring us closer to average or cutoff lows reigning supreme come fall.

[Stormchaserchuck1]

Powerful heatwave headed for Europe too, as the strong +NAO spins out over the next few days.. 5940dm tropical jet makes it to Paris, France. 

[snowman19]

La Nina is also somewhat of a -WPO indicator.. Indian Ocean didn't look like it had strong SSTA's that year. I would look at the map and say slightly negative projection. 

We now have model consensus on a -IOD developing during the summer and fall

[bluewave]

35 minutes ago, snowman19 said:

We now have model consensus on a -IOD developing during the summer and fall

The extension of the record Aleutian Ridge closer to Japan has actually slowed the start of the rainy season there with the record heat.
 

 

[40/70 Benchmark]

9 hours ago, Stormchaserchuck1 said:

Dec 2021 actually had an all time record breaking Aleutian ridge.. it reached +600 for a couple of days at its max! I know 21-22 is the only -WPO Winter since 16-17, but the -PNA was more powerful that Winter. The Aleutian ridge just went poleward. 

My early hunch is ample poleward Aleutian ridging with -PNA.

[40/70 Benchmark]

9 hours ago, Stormchaserchuck1 said:

La Nina is also somewhat of a -WPO indicator.. Indian Ocean didn't look like it had strong SSTA's that year. I would look at the map and say slightly negative projection. 

No, my point was it was warmer than 2021...not that it was very warm, per se...

[40/70 Benchmark]

9 hours ago, Stormchaserchuck1 said:

June will be the 5th month in a row with +NAO

4th straight month of +AO

4th straight month of -PNA

Quite a streak for bad indexes if it were Winter lol

I actually like seeing that this time of year, anecdotally speaking, anyway...no correlation maps or anything haha.

[40/70 Benchmark]

49 minutes ago, snowman19 said:

We now have model consensus on a -IOD developing during the summer and fall

Yea, I don't think those warming subsurface trends will continue much longer. Do you have the source for your long range IOD forecast?

[snowman19]

Yea, I don't think those warming subsurface trends will continue much longer. Do you have the source for your long range IOD forecast?

BOM

http://www.bom.gov.au/climate/enso/?ninoIndex=nino3.4&index=nino34&period=weekly

[40/70 Benchmark]

13 minutes ago, snowman19 said:

BOM

http://www.bom.gov.au/climate/enso/?ninoIndex=nino3.4&index=nino34&period=weekly

Seems to be a pretty weak consensus...

El Niño–Southern Oscillation and Indian Ocean Dipole remain neutral; negative IOD possible in late winter to early spring