2026-2027 Super El Nino

[Stormchaserchuck1]

^That's a good point. Definitely watch the S. Hemisphere Winter to see if it's propagating to the mid latitude Cell. Pretty good correlation you found there, I like how it's a sea of yellow otherwise. 

[snowman19]

7 hours ago, Stormchaserchuck1 said:

+7c has popped in the far east, highest of the event so far. Still warming.  Definitely taking on an east-based look

Agreed

 

 

 

[GaWx]

 Not surprisingly being that the crazy high 0Z 5/25/26 run was likely the strongest CFSv2 ensemble mean +AAM prog since at least 2023, it has come way down since. As I’ve said a number of times, it’s the CFSv2 long range and thus while worth following and posting, s/b taken with a huge grain.

0Z 5/25/26 run: mean peak ~+3.5 late June!

12Z 5/28/26 run: mean peak way down to only ~+1 in late June: like night and day!

[Stormchaserchuck1]

32 minutes ago, snowman19 said:

Agreed

 

 

 

Last image of that NASA SLH makes me wonder if we are setting up a big La nina roll back, with the way it's unfolding so east and that cold subsurface water popping north of New Guinea. I think the tendency is +ENSO for 2-3 years relative to swings and stuff so we'll see. 

[GaWx]

12 minutes ago, snowman19 said:

Either way the AAM is going positive

It’s already positive (~+1.7)as per the latest CFSv2 initialization posted above. That was well predicted on that insane 0Z 5/25 run as one can see.

[so_whats_happening]

8 hours ago, Stormchaserchuck1 said:

In other news, we have a pretty good +AO setting up for the early Summer (May-June), for the 3rd consecutive year. 

It has been something I have been watching for a bit. We don't seem to have the preconditioning issues of April through early June we saw over last 15 or so years prior to the switch up. No miraculous comeback by any means but interesting to see the change up. Very similar to 2000-2009 timeframe for April to June.

[raindancewx]

May 2026 nationally looks a lot like May 1997, 1994, and 1940. Somewhat like 2006 and 2009.

Not really like 2015 or 2023 or 1982 or 1965 or 1972 or 1957 or 1991.

Actually pretty unusual for the NW/West to be the warmest area of the US with El Nino conditions.

 

Locally, April and May have so far trended similarly to average April-May highs following our hottest Marches ever. 

December and August both have 4-5 years in the 10 hottest March grouping that are at least two degrees colder than long-term average highs.

For August, only 17 years for 1931-2025 are 2F are more below the 95 year average. So it's 12/85 v 5/10 if you separate out the hottest March years.

If your hypothesis is "August following a top-ten warm March" has the same frequency of cold highs as any other March, a difference in proportions test would say you are wrong because the P value is ~0.004 - well under 0.05. 

Only 48/95 Augusts are colder than average for highs locally. But 7/10 are following a top 10 hot August.

41 / 85 v. 7/ 10 is not statistically significant. So if we have a cold August, its likely to be quite cold, but its not meaningfully more likely that we have a cold August locally.

2026	52.5	62.7	76.5	73.3	80.0	M	M	M	M	M	M	M	69.0
1972	51.2	58.7	71.1	75.2	81.2	90.3	93.1	86.4	80.6	68.3	50.9	47.3	71.2
1974	45.6	53.7	69.5	73.3	85.4	96.3	90.9	85.5	78.4	68.6	58.0	43.7	70.7
2017	48.9	58.4	69.4	70.5	78.4	93.2	92.1	88.0	83.6	72.1	65.4	53.1	72.8
1989	47.9	54.9	68.8	77.8	85.1	90.5	92.1	86.8	82.8	69.5	60.2	47.7	72.0
2011	48.1	50.5	67.4	72.6	77.9	93.6	94.5	93.8	82.9	71.4	57.2	42.8	71.1
1967	48.1	54.7	67.3	72.7	79.3	85.7	92.2	86.7	81.1	73.4	59.7	41.9	70.2
1934	51.0	58.5	67.0	72.7	83.3	88.9	94.8	90.6	80.9	75.3	57.8	49.0	72.5
1997	43.5	51.5	66.7	64.1	78.7	86.3	90.0	87.9	82.8	69.9	54.5	41.7	68.1
2015	47.9	57.3	66.3	70.1	74.0	90.8	88.4	91.5	86.2	72.0	56.9	46.9	70.7
2016	47.5	59.8	66.2	68.9	77.1	93.3	95.6	85.8	83.2	75.9	58.6	49.7	71.8

[GaWx]

Check out this 19 day sub -5 SOI streak along with today’s -33.46 being 2nd most negative (barely missing 1st) so far this year. Note that Darwin’s higher than avg SLP for May has the last 10 days finally joined Tahiti’s lows to contribute. Darwin SLPs look to remain on the high side at least over the next week or so per models:

2026 131 1012.47 1012.15   -9.25
2026 132 1011.99 1012.00  -11.78
2026 133 1010.40 1010.50  -12.47
2026 134 1009.81 1010.30  -15.45
2026 135 1009.15 1010.00  -18.21
2026 136 1008.21 1009.70  -23.11
2026 137 1007.49 1009.55  -27.48
2026 138 1009.98 1009.25   -6.11
2026 139 1011.63 1010.85   -5.73
2026 140 1012.01 1012.45  -15.07
2026 141 1010.85 1013.05  -28.55
2026 142 1012.15 1013.20  -19.74
2026 143 1011.70 1012.55  -18.21
2026 144 1010.19 1012.80  -31.69
2026 145 1011.06 1012.85  -25.41
2026 146 1013.30 1012.45   -5.19
2026 147 1013.80 1013.10   -6.34
2026 148 1012.81 1014.30  -23.11
2026 149 1011.31 1014.15  -33.46

[bluewave]

Starting to see the seasonal -PDO drop heading into summer which has been common during the the 2020s.

 

[GaWx]

3 minutes ago, bluewave said:

Starting to see the seasonal -PDO drop heading into summer which has been common during the 2020s.

 

Also, keep in mind that a -1.40 WCS daily PDO is generally equivalent to a sub-2 NOAA daily PDO. This differential has been the case since I started following WCS daily PDOs years ago.

[bluewave]

2 minutes ago, GaWx said:

Also, keep in mind that a -1.40 WCS daily PDO is generally equivalent to a sub-2 NOAA daily PDO. This differential has been the case since I started following WCS daily PDOs years ago.

My guess is that the recent drop was enhanced by the +EPO -PNA pattern in May.

 

 

[BlizzardWx]

My calculation has -1.18 for the PDO, so at least relatively in line with WCS. It's definitely been dropping the last few weeks. But the AMO is looking solidly negative now, so that is new compared to recent history. 

[GaWx]

2 minutes ago, BlizzardWx said:

My calculation has -1.18 for the PDO, so in line with WCS. It's definitely been dropping the last few weeks. But the AMO is looking solidly negative now, so that is new compared to recent history. 

You have the PDO only down to -1.18 now? Do you mean current daily? How did you calculate that? I ask because that seems not nearly negative enough if you’re talking current daily.

[snowman19]

 

Translation: “The atmospheric indicators required for the equatorial Pacific warming to be fed back from the atmosphere (ocean-atmosphere coupling) are already visible: a strong negative value of the Southern Oscillation Index, a decrease in OLR (Outgoing Longwave Radiation) in the central-eastern equatorial Pacific (in fact, it is already reaching the values of analogous observed events), and a weakening of the trade winds (850mb) between the coast of South America and the international date line.

All these parameters are consistent with the presence and consolidation of #ElNiño. The MJO is playing a role in this, over the last few days.”

^This along with the AAM popping positive are all consistent with a strongly coupling (Bjerknes feedback) El Niño event

 

 

 

“A massive westerly wind burst is currently commencing across the West/Central Pacific. As it moves East, this is likely going to kick El Niño into overdrive. All ENSO regions are already solidly above average, and this even will likely help push the warm pool (with record SSTs in many spots) further east into the East/Central Pacific.”

 

[BlizzardWx]

51 minutes ago, GaWx said:

You have the PDO only down to -1.18 now? Do you mean current daily? How did you calculate that? I ask because that seems not nearly negative enough if you’re talking current daily.

Yeah, that is what my page shows as of the 27th for the daily value. As for how I did it, that's an important point to dwell on for any PDO calculation. It's dependent on the period of record, the exact domain, how much you correct the climate change signal, etc. All of these effect the EOF calculation that defines the weights that can then be used in the actual calculation. None of this is clearly standardized anywhere, which is why different groups get different values. I think that mine and WCS are better than NOAA who does not appear to have detrended the climate change signal properly. 

[bluewave]

20 hours ago, roardog said:

These guys are talking about atmospheric responses like WWB,MJO,SOI, etc. I don’t think anyone here disagrees with any of this. Posters like Bluewave and Chuck are talking about the pattern over the North Pacific and or North America not being completely Nino like. I’m still not even sure why we should even be expecting a strong Nino response right now since the RONI is at like +.5

Yeah, we can see the overlapping influences between the El Niño, MJO, and -PDO heading into early June.

The ridging showing up south of Alaska into Western Canada is the correlation with the El Nino and +AAM.

The extension of the ridge further east across much of the CONUS is more -PDO and MJO 8-1 related for this time of year.

So effectively a 500 mb composite in early June that reflects these influences. A coupled El Niño will vary in its sensible weather related to the other influences. 

Also the pattern in recent years of the 500 mb ridges becoming stronger and more expansive with weaker troughs during any given ENSO state.

[40/70 Benchmark]

1 hour ago, snowman19 said:

@Stormchaserchuck1 If we have (finally) turned the corner in the Atlantic to a solid -AMO cycle, what implications does that have on the NAO? 

Not that it is going to flip on a dime, but the last -AMO cycle coincided with the negative portion of the multidecadal NAO cycle in the 60s. I think we are more likely to see a modified version of that (CC) around and after the solar min early next decade. This season should be decidedly positive.

[40/70 Benchmark]

42 minutes ago, bluewave said:

Yeah, we can see the overlapping influences between the El Niño, MJO, and -PDO heading into early June.

The ridging showing up south of Alaska into Western Canada is the correlation with the El Nino and +AAM.

The extension of the ridge further east across much of the CONUS is more -PDO and MJO 8-1 related for this time of year.

So effectively a 500 mb composite in early June that reflects these influences. A coupled El Niño will vary in its sensible weather related to the other influences. 

Also the pattern in recent years of the 500 mb ridges becoming stronger and more expansive with weaker troughs during any given ENSO state.

This is why I feel we want a high RONI during an El Nino event....the RONI represents a spectrum, or continuum if you will, of the ability of warm ENSO to modulate the north Pacific versus the baseline trend that is more reflective of CC, which is cool ENSO like. I think folks obfuscate this with the MEI, which simply measures the intensity of the warm ENSO coupling. RONI is not so much about the intensity of the coupling, but the war waged between ENSO and competing hemispheric forces.

[GaWx]

15 minutes ago, 40/70 Benchmark said:

This is why I feel we want a high RONI during an El Nino event....the RONI represents a spectrum, or continuum if you will, of the ability of warm ENSO to modulate the north Pacific versus the baseline trend that is more reflective of CC, which is cool ENSO like. I think folks obfuscate this with the MEI, which simply measures the intensity of the warm ENSO coupling. RONI is not so much about the intensity of the coupling, but the war waged between ENSO and competing hemispheric forces.

 Besides the MEI, I feel that the SOI (which may be part of the MEI…Is it?) remains a good measure of the phase and strength of ENSO because it is a calculation based on SLP differences between two points thousands of miles apart and thus doesn’t seem to be influenced by CC. In essence a relative SOI is likely not needed. Of course, because it is so volatile and subject to day to day randomness, it’s best looked at in 30+ day averages.

 Then again, if, say avg. Australian SLPs have been affected by CV differently from how Tahiti SLPs have been affected by CC, then even SOIs would need an adjustment.

Other opinions?

[40/70 Benchmark]

20 minutes ago, GaWx said:

 Besides the MEI, I feel that the SOI (which may be part of the MEI…Is it?) remains a good measure of the phase and strength of ENSO because it is a calculation based on SLP differences between two points thousands of miles apart and thus doesn’t seem to be influenced by CC. In essence a relative SOI is likely not needed. Of course, because it is so volatile and subject to day to day randomness, it’s best looked at in 30+ day averages.

 Then again, if, say avg. Australian SLPs have been affected by CV differently from how Tahiti SLPs have been affected by CC, then even SOIs would need an adjustment.

Other opinions?

Yea, air pressure is an element of the MEI, I believe.

[40/70 Benchmark]

1 minute ago, 40/70 Benchmark said:

Yea, air pressure is an element of the MEI, I believe.

It is.

The Multivariate ENSO Index (MEI.v2) is a comprehensive climate index used to measure the intensity and phase of the El Niño-Southern Oscillation (ENSO). It improves upon single-variable indices by combining five oceanic and atmospheric variables across the tropical Pacific: sea surface temperatures, sea-level pressure, surface winds, and outgoing longwave radiation

[so_whats_happening]

[bluewave]

1 hour ago, 40/70 Benchmark said:

This is why I feel we want a high RONI during an El Nino event....the RONI represents a spectrum, or continuum if you will, of the ability of warm ENSO to modulate the north Pacific versus the baseline trend that is more reflective of CC, which is cool ENSO like. I think folks obfuscate this with the MEI, which simply measures the intensity of the warm ENSO coupling. RONI is not so much about the intensity of the coupling, but the war waged between ENSO and competing hemispheric forces.

I think that it could also go beyond the RONI in that the 500 mb ridges are expanding in the mid-latitudes outside the tropical oceans which RONI measures.

The 500 mb ridge across the North Pacific from east of Japan to south of the Aleutians has been unprecedented during the 2020s. Also note the slightly weaker mirroring of the pattern in the South Pacific to the east of New Zealand. 

So it’s been warming the SSTs underneath the ridge causing the -PDO to remain negative. In the old days ,the -PDO was more a function of colder SSTs off of California rather than the extensive warm pool from east of Japan to south of the Aleutians that we have today.
 

 

[40/70 Benchmark]

12 minutes ago, bluewave said:

I think that it could also go beyond the RONI in that the 500 mb ridges are expanding in the mid-latitudes outside the tropical oceans which RONI measures.

The 500 mb ridge across the North Pacific from east of Japan to south of the Aleutians has been unprecedented during the 2020s. Also note the slightly weaker mirroring of the pattern in the South Pacific to the east of New Zealand. 

So it’s been warming the SSTs underneath the ridge causing the -PDO to remain negative. In the old days ,the -PDO was more a function of colder SSTs off of California rather than the extensive warm pool from east of Japan to south of the Aleutians that we have today.
 

 

Well, it's all connected...sure, the RONI only measures the oceans, but I think the warming oceans are somewhat connected to the more pronounced 500MB ridges....I think there is an element of feedback at play. Bottom line is there is more heat, which is being reflected in the ocean and the atmosphere, but it just so happens that the RONI only measures the former...so technically, yes...it certainly goes beyond the RONI.

[Stormchaserchuck1]

3 hours ago, snowman19 said:

@Stormchaserchuck1 If we have (finally) turned the corner in the Atlantic to a solid -AMO cycle, what implications does that have on the NAO? 

I think it would favor more -NAO events going forward (decadally). 

Be careful that you are calling the -AMO right now is not from a lot of +NAO/+AO, especially in the warm season. Immediate term the central-south Atlantic has -0.3 to -0.4 SSTA correlation with +NAO conditions. I know, correlated immediately, inverse in the long term. 

[Stormchaserchuck1]

I'm wondering if TAO/Triton will pop a +8c in the subsurface in the next few days, as it continues to warm. It's really taking on a Strong east-based dominance. 

[PhiEaglesfan712]

New York Post posted an article about Mt. Rainier possibly erupting: https://nypost.com/2026/05/29/science/most-dangerous-us-volcano-mt-rainier-could-devastate-60000-residents/

This is probably the only thing that can prevent another temperature jump from this upcoming el nino.

Remember that Pinatubo erupted in mid-June 1991, ahead of a robust el nino.

[Stormchaserchuck1]

Last year March - October was all +AO monthly, 8/8 months. It looks like this March - June will be starting off +AO, 4/4 months. 

Edit: It looks like a east-based Nino/-PDO Winter composite, when rolled forward. I always like 2nd points to the same probability. 

[SnoSki14]

Man the northeast is so cooked next winter. 

[MJO812]

5 hours ago, SnoSki14 said:

Man the northeast is so cooked next winter. 

We are only in May LOL. Come back in October or even November to talk about the winter.