2026-2027 Record-breaking El Nino

[GaWx]

1 hour ago, bluewave said:

I think that’s why the long range models continue the WWBs and the extreme east based nature of this event right into next June. 

 

 

25 minutes ago, Maestrobjwa said:

Next June? Dang does that usually happen? Thought there was mention of a rebound nina 

 Looking at El Niño seasons that at some point maxed out at +2.0C for a trimonthly in Nino 3.4 (using Eric Webb’s tables for pre-1950 and the latest version of NOAA RONI for 1950+), this is what followed in ASO as well as the subsequent fall/winter:

1877-8: ASO +0.1 followed by cold neutral
1888-9: ASO -1.1 followed by strong La Niña
1965-6: ASO 0.0 followed by cold neutral
1972-3: ASO -1.3 followed by strong La Niña
1982-3: ASO -0.6 followed by moderate La Niña
1991-2: ASO +0.1 followed by weak El Niño
1997-8: ASO -1.2 followed by strong La Niña
2015-6: ASO -0.9 followed by moderate La Niña


Tally for these 8 strongest El Niños on record:

5 La Niña (3 strong, 2 moderate) (62.5%)
2 cold neutral (25%)
1 weak El Niño (12.5%)

So, this suggests the best chance is clearly for La Niña although it also suggests to not dismiss the possibility of something else, mainly cold neutral, especially IF this were to peak later than model consensus has been suggesting (say, in Jan instead of Nov). Of the 3 of these that didn’t go to La Niña, 1877-8 peaked between NDJ and DJF while 1991-2 peaked in DJF. OTOH, 1965-6 peaked early (OND) and still didn’t go all the way to La Niña the following year as it stopped at cold neutral. Note that the 3 that were neutral in ASO never made it to La Niña.
____________________

Sources of data:

1. Webb’s tables (used for pre-1950):

https://www.webberweather.com/ensemble-oceanic-nino-index.html

 

2. NOAA RONI (1950+):
https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso/roni/

[40/70 Benchmark]

The JJA summer composite was not El Nino like, but August was.

[GaWx]

 Ok, here we go again with the BoM RONI progs. As I’ve posted, the early near month prog of every near month of Apr-Aug ended up having been too warm as per their charts showing notably cooler in their final analyses vs these early progs. I now feel safe in saying that that’s happening with Sep, too, which would make 6 months in a row!

 Here was a Sep 5th prog, which had Sep near +3.0:

 Compare that to the brand new run (Sep 26th…see below), which has Sep MTD at only +2.4 with only 5 days to go (note the line from Aug to Sep is almost flat vs the steep slope of the Sep 5th run)! To compare, NOAA appears to be headed to a Sep of only ~+2.0 to +2.2.

 
 We’ll see next week where Sep. settles for both BoM and NOAA. I bet BoM settles at ~+2.5 or +2.6, well below its Sep 5th run’s +3.0 prog.

 Thus, I continue to expect that the ~+3.8 peak that it still shows for Nov will end up not verifying even closely. Before that, I predict with confidence that the +3.5 of Oct won’t verify closely. Why would the clearcut pattern of significantly too warm near month progs change now?

 Besides, it would take pretty much a record warming for a one month period to reach from Sep’s mid +2s to Oct’s +3.5. Sound familiar? Several models earlier had predicted a record warming from July to August, which we know ended up busting badly.

 To show how out of touch with reality this has been the last 3 months, this Jul 4th run had July at +2.0, Aug at +2.7, and Sep at +3.0. Jul/Aug BoM verified at only +1.7/+2.3 and Sep should verify only in the +2.5 to +2.6 area as mentioned. This warm bias is Déjà vu from 2023:

[bluewave]

18 hours ago, GaWx said:

 

 Looking at El Niño seasons that at some point maxed out at +2.0C for a trimonthly in Nino 3.4 (using Eric Webb’s tables for pre-1950 and the latest version of NOAA RONI for 1950+), this is what followed in ASO as well as the subsequent fall/winter:

1877-8: ASO +0.1 followed by cold neutral
1888-9: ASO -1.1 followed by strong La Niña
1965-6: ASO 0.0 followed by cold neutral
1972-3: ASO -1.3 followed by strong La Niña
1982-3: ASO -0.6 followed by moderate La Niña
1991-2: ASO +0.1 followed by weak El Niño
1997-8: ASO -1.2 followed by strong La Niña
2015-6: ASO -0.9 followed by moderate La Niña


Tally for these 8 strongest El Niños on record:

5 La Niña (3 strong, 2 moderate) (62.5%)
2 cold neutral (25%)
1 weak El Niño (12.5%)

So, this suggests the best chance is clearly for La Niña although it also suggests to not dismiss the possibility of something else, mainly cold neutral, especially IF this were to peak later than model consensus has been suggesting (say, in Jan instead of Nov). Of the 3 of these that didn’t go to La Niña, 1877-8 peaked between NDJ and DJF while 1991-2 peaked in DJF. OTOH, 1965-6 peaked early (OND) and still didn’t go all the way to La Niña the following year as it stopped at cold neutral. Note that the 3 that were neutral in ASO never made it to La Niña.
____________________

Sources of data:

1. Webb’s tables (used for pre-1950):

https://www.webberweather.com/ensemble-oceanic-nino-index.html

 

2. NOAA RONI (1950+):
https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso/roni/

Even though the CFS forecast was too weak with the current all-time daily +5 Nino 1+2, it has a 2nd peak late next spring into the early summer.

These very long range forecasts aren’t as accurate. But even the Euro extended is showing something similar.

1982-1983 had a second Nino 1+2 peak in June 1983 which was stronger than the one from the fall. But this fall is so much stronger than 1982 that the models have a lower peak late next spring. 

The 1983-1984 La Niña was significantly weaker than 1998-1999 since it got off to such a late start with a much weaker cold pool.

We’ll get a new update on October 5th to see if it has the same forecast idea from the August 5th extension. The Euro was much closer to the current +5 than the CFS.

 

 

 

 

[OSUmetstud]

Nino 1+2 is going to verify on the high side of early month released models in contrast to nino 4 verifying on the low end. Some of the real small decreases in nino 3.4 near term rises continue to be the direct result of this nino being incredibly strong and super east based not because of any weakness. Peak sst anomalies on the latest ecmwf product are over 7C and are mainly centered in 3 and 1+2 not as much in 3.4. 

[OSUmetstud]

Anomaly increases the past 15 days.

[40/70 Benchmark]

58 minutes ago, bluewave said:

Even though the CFS forecast was too weak with the current all-time daily +5 Nino 1+2, it has a 2nd peak late next spring into the early summer.

These very long range forecasts aren’t as accurate. But even the Euro extended is showing something similar.

1982-1983 had a second Nino 1+2 peak in June 1983 which was stronger than the one from the fall. But this fall is so much stronger than 1982 that the models have a lower peak late next spring. 

The 1983-1984 La Niña was significantly weaker than 1998-1999 since it got off to such a late start with a much weaker cold pool.

We’ll get a new update on October 5th to see if it has the same forecast idea from the August 5th extension. The Euro was much closer to the current +5 than the CFS.

 

 

 

 

This is a stronger version of 1982 with the main difference being the warm pool east of Japan, hence the lower PDO....But QBO, solar, east-based super El Nino trying to shift more basin-wide mid season and the secondary 1.2 peak.

Elite analog...about as good as it gets.

[40/70 Benchmark]

In case there was any doubt as to where the west Pacific warm pool has migrated.....

 

3 hours ago, Windspeed said:

Nolo is looking spectacular this morning and well on its way to becoming another 2026 EPAC/CPAC Category 5.

 

[OSUmetstud]

Traditionally weekly noaa sst anomalies are at record in 1.2, 3, and 3.4 now. 

[OSUmetstud]

Btw, the bom forecast for roni 3 was spot on from last month. Like other agencies the roni 4 was a big positive bias fail. 

[bluewave]

38 minutes ago, 40/70 Benchmark said:

This is a stronger version of 1982 with the main difference being the warm pool east of Japan, hence the lower PDO....But QBO, solar, east-based super El Nino trying to shift more basin-wide mid season and the secondary 1.2 peak.

Elite analog...about as good as it gets.

The current forecasts have it more east based mid-season than 1982-1983. That one was more full basin than 1997-1998  during the winter. With it becoming most east based late spring into early summer 1983. Which was part of the reason that February 1983 was better than 1998.

[GaWx]

 ^Thanks. Here is this morning’s NOAA weekly update for relative (for those who don’t know, this much better takes into account GW and thus became the official way of measuring by NOAA a good while ago) Nino anomalies for the average of last week compared to the avg for the prior week: this shows 1+2 still at +3.9 and the other 3 having warmed 0.1. Below that are the comparable weeks in 1997 and 1982:
 

16SEP2026         3.9        3.0        2.1        0.0
 23SEP2026        3.9         3.1          2.2        0.1

 

24SEP1997         3.8        2.7        1.8        0.5 (the most E based prior to 2026)

 

22SEP1982         1.5        2.1        2.0        0.6
 

 Compared to past years for the same week, 1+2 region’s +3.9 remains at its highest (weekly records back to 1981) for the 2nd week in a row, beating 1997’s +3.8. Next Monday’s release will likely be the 3rd week in a row at its highest.

 Nino 3’s +3.1 is its 2nd week in a row of being at a high with it easily beating 1997’s +2.7. 

 Nino 3.4’s +2.2 beats 1982’s +2.0 for the warmest for that week and is its 3rd week in a row at a high.

 Nino 4’s +0.1 is way cooler than the other regions and also is significantly cooler than many years thus showing how much more E based 2026 is vs any other year on record as of late Sept including the prior most E based 1997:

1994 +0.9

1986 +0.8

2019 +0.7

2002 +0.7

2006 +0.6

2004 +0.6

2023 +0.5

1997 +0.5

https://www.cpc.ncep.noaa.gov/data/indices/rel_wksst9120.txt

@bluewave@OSUmetstud@40/70 Benchmark

[40/70 Benchmark]

20 minutes ago, bluewave said:

The current forecasts have it more east based mid-season than 1982-1983. That one was more full basin than 1997-1998  during the winter. With it becoming most east based late spring into early summer 1983. Which was part of the reason that February 1983 was better than 1998.

1982 was very east-based early in the season, as well. The forecast is more east-based in terms of SSTs mid-season, but I don't know how much that will matter given the warm pool in the central Pacific.

A large reason why 1997 was better early and 1982 was better later was the stratosphere.

[40/70 Benchmark]

There is a reason why 2023 had MC forcing despite having record anomalies in region 4.....warm pool was in the west Pac. This year, record anomalies are over eastern ENSO, but the warm pool is in the western half of ENSO. Look at where the seasonal models place the forcing...no shock.

[bluewave]

13 minutes ago, 40/70 Benchmark said:

1982 was very east-based early in the season, as well. The forecast is more east-based in terms of SSTs mid-season, but I don't know how much that will matter given the warm pool in the central Pacific.

A large reason why 1997 was better early and 1982 was better later was the stratosphere.

The east based nature of 1982-1983 backed off during the winter relative to 1997-1998.

The stratospheric conditions were related to the different nature of the ENSO forcing between both those seasons.

The Central Pacific warm pool has already shifted the farthest to the east it has ever been. This is only expected to increase in the coming months.

[Typhoon Tip]

Man ...that 3.4 is astounding really. 

Just a cursory evaluation and comparison of these curves,  https://climatereanalyzer.org/clim/sst_daily/?dm_id=nino3.4

.. what sets this year apart is that every curve there, other than the present year's ongoing ... demoed a period of downward trajectory between mid spring to early autumns.   One can make that out just eyeballing, but if you looked at May1 to September15-ish period trend lines, even 2015 was slightly negative during that span of time.  Otherwise, they were more demonstratively so.  

Yet, the 3.4 has risen the entire time... straight through what one can only surmise was/is a climate normal behavior for an intermediate nadir.  So, for first time at least among these years since 2008 there was no intermediate negative recovery.  I wonder if this would be so for all years -

It's a nuance ob but it's true nonetheless.   The other obvious elephant in this picture is that this 3.4 is like that jet at a memorial fly by that peals away toward the heavens..

I just find that specific aspect about the trend line since May 1/summer behavior to be interesting for unique behavior.

[40/70 Benchmark]

36 minutes ago, bluewave said:

The east based nature of 1982-1983 backed off during the winter relative to 1997-1998.

The stratospheric conditions were related to the different nature of the ENSO forcing between both those seasons.

The Central Pacific warm pool has already shifted the farthest to the east it has ever been. This is only expected to increase in the coming months.

Yes, but you keep neglecting the fact that did in fact begin severely east-based.

No, the stratospheric conditions were different due to the QBO (west this year and 1982, east in 1997) and the solar cycle (high and descending this year and 1982 versus low and ascending in 1997), not ENSO. I think there is some connection between ENSO and the solar cycle on a larger scale, which is why the most intense El Nino events usually coincide with descending solar, post max, but it's more solar driving ENSO, not vice versa  ENSO orientation does have some direct impact on the NAO, but it's more Modoki that specifically favors -NAO....basin-wide is more variable and depends on other extraneous factors, such as the strat, and solar cycle.

No guidance forecasts the warm pool to near the Mexican coast....if you have anything that does, then by all means...present it. Could it make it further east than all guidance currently depicts, sure....not I doubt it's off by that much. Guidance places forcing in a very similar spot to 1983 despite any disparity in the orientation of El Nino in the respective of years bc of where that pool of 30c+ water resides.

.

[bluewave]

1 hour ago, GaWx said:

^Thanks. Here is this morning’s NOAA weekly update for relative (for those who don’t know, this much better takes into account GW and thus became the official way of measuring by NOAA a good while ago) Nino anomalies for the average of last week compared to the avg for the prior week: this shows 1+2 still at +3.9 and the other 3 having warmed 0.1. Below that are the comparable weeks in 1997 and 1982:

RONI is a relative metric to SST outside the actual ENSO regions. But the BOM RONI for Nino 1 and 2 are higher close to the actual ONI readings.

So this is why we maintain the ONI alongside the RONI. Plus the agencies in South America use both since the record streak of temperatures there are related to the actual ONI readings. 

Remember Nino 1+2 has been one of the few ocean regions of the planet which didn’t warm prior to the 2023-2024 super El Niño. 
 

https://www.cpc.ncep.noaa.gov/data/indices/

23SEP2026     25.4 4.7     28.8 3.9     29.7 3.1     29.8 1.1

 

[40/70 Benchmark]

36 minutes ago, 40/70 Benchmark said:

Yes, but you keep neglecting the fact that did in fact begin severely east-based.

No, the stratospheric conditions were different due to the QBO (west this year and 1982, east in 1997) and the solar cycle (high and descending this year and 1982 versus low and ascending in 1997), not ENSO. I think there is some connection between ENSO and the solar cycle on a larger scale, which is why the most intense El Nino events usually coincide with descending solar, post max, but it's more solar driving ENSO, not vice versa  ENSO orientation does have some direct impact on the NAO, but it's more Modoki that specifically favors -NAO....basin-wide is more variable and depends on other extraneous factors, such as the strat, and solar cycle.

No guidance forecasts the warm pool to near the Mexican coast....if you have anything that does, then by all means...present it. Could it make it further east than all guidance currently depicts, sure....not I doubt it's off by that much. Guidance places forcing in a very similar spot to 1983 despite any disparity in the orientation of El Nino in the respective of years bc of where that pool of 30c+ water resides.

.

Expounding on this point....December 1997 in one of the most intense, east-based El Nino events in recorded history, yet had a decent -NAO.

 

Why? Take a look at where 1997 occurs in the solar cycle (left side of chart) in conjunction with a strong easterly QBO....your overreliance on ENSO as a modulator of the NAO is too reductive here, Chris.

Now check where 2026 falls...

And every other super-El Nino....

 

Why is blocking favored GENERALLY earlier during E QBO and later during W QBO?

Holton-Tans relationship.

Integrating Solar & QBO Research for a Comprehensive Polar Forecast

The aforementioned Holton-Tan relationship, which dictates that an easterly QBO is correlated with both a greater incidence of, and an earlier development of SSW, becomes more complicated when considering the solar cycle. In some cases, when the QBO and solar cycle are in conflict, they can either over ride one another or even cancel each other out (Gray et al 2004). Here is a list of combinations and the theorized relationships for clarity.

Solar min/W QBO: This is entirely consistent with the Holton-Tan relationship in that the westerly QBO essentially "wins".

Solar max/W QBO: In this case, the Holton-Tan relationship is applicable early on in the season, as major warmings are unlikely. However, the Holton-Tan relationship reverses mid winter and the latter portion of the season from February onward is susceptible to warmings and major PV disruption. Winter 2024-2025 was a textbook example of this.

Since winter 2026-2027 will occur in the descending phase between the max of solar cycle 25 and the min that will occur early next decade, each of these previous two scenarios warrant consideration with a preference for the former, solar min/W QBO data set given the geomagnetic energy is will likely be peaking during break winter 2026-2027, thus any SSW will likely be delayed until latter February, or more likely a final waring in March. This does NOT necessarily preclude the incidence of minor warming and/or tropospheric wave breaking earlier, though.

Solar Min/E QBO: There are no inconsistencies here, as the entire season is more prone to polar vortex disruptions and SSW as per the Holton-Tan relationship.

Solar Max/E QBO : The Holton-Tan relationship applies early on given that PV disruptions are likely in December, before the relationship reverses and they are less likely later in the season. The final warming is of course the exception to this rule, while it is usually more relevant for spring, it can and does sometimes occur early enough to have an impact for the major population centers in terms of late season cold and/or snowfall.

Below are a couple of annotations to aide in the simplification and visualization of these relationships.

[40/70 Benchmark]

I think this season will feature late blocking via wave reflection rather than a SSW given the combination of descending solar and W QBO, but the strong signal among guidance (likely overstated) in conjunction with the strong match to 1983 buttresses this postulation....all of this in conjunction with the locale of the warm pool in the central Pacific renders any westward propagation of ENSO merely a constructive interference bonus of sorts, but not a requisite development.

[40/70 Benchmark]

My theory on why 1997 occurred where it did in the solar cycle is that it was Earth's response to the early acceleration of CC.

[bluewave]

36 minutes ago, 40/70 Benchmark said:

Yes, but you keep neglecting the fact that did in fact begin severely east-based.

No, the stratospheric conditions were different due to the QBO (west this year and 1982, east in 1997) and the solar cycle (high and descending this year and 1982 versus low and ascending in 1997), not ENSO. I think there is some connection between ENSO and the solar cycle on a larger scale, which is why the most intense El Nino events usually coincide with descending solar, post max, but it's more solar driving ENSO, not vice versa  ENSO orientation does have some direct impact on the NAO, but it's more Modoki that specifically favors -NAO....basin-wide is more variable and depends on other extraneous factors, such as the strat, and solar cycle.

No guidance forecasts the warm pool to near the Mexican coast....if you have anything that does, then by all means...present it. Could it make it further east than all guidance currently depicts, sure....not I doubt it's off by that much. Guidance places forcing in a very similar spot to 1983 despite any disparity in the orientation of El Nino in the respective of years bc of where that pool of 30c+ water resides.

.

The stratospheric interactions are also related to the actual tropical forcing in addition to the state of the QBO. 

During the later portion of the winter in 1983, it was more of a full-basin SST configuration compared to 1997-1998. 

All the guidance has a warm pool extending up along the West Coast of Mexico. This along with the record warmth in 1-2 and 3 lead to the forecast for split forcing leading to a strong eastward lean. 

During many recent seasons warm pools off the equator had had areas of forcing west of Mexico and to the east of Hawaii. 

 

 

 

[40/70 Benchmark]

19 minutes ago, bluewave said:

The stratospheric interactions are also related to the actual tropical forcing in addition to the state of the QBO. 

During the later portion of the winter in 1983, it was more of a full-basin SST configuration compared to 1997-1998. 

All the guidance has a warm pool extending up along the West Coast of Mexico. This along with the record warmth in 1-2 and 3 lead to the forecast for split forcing leading to a strong eastward lean. 

During many recent seasons warm pools off the equator had had areas of forcing west of Mexico and to the east of Hawaii. 

 

 

 

Well, you have the SST anomaly map....if you look at absolute SSTs, they are mainly relegated to the central Pacific. I believe you have stated in the past that bc of CC we have crossed a critical threshold whereas convective forcing is now dictated more by there the SSTs in excess of 30C are as opposed to the greatest anomalies.

Yes, I agree on the split forcing.....this is the competing convection between the warm pool and ENSO. I feel it will be weighted more towards ENSO early, and flip to more warm pool guided for a time mid season into February. If you look at the modeled rainfall rates, they actually favor the central convection.

Perhaps the most prominent impact of climate change is the battle royale that is constantly  waged between a plethora of competing sources of convective forcing given the unprecedented degree of heat that is stored in the oceans as the climate continues to warm at an accelerating rate. Winter 2026-2027 is poised to provide those on the east coast with a front row seat to the main card match facilitated by an immense barrage of WWBs between two juggernaut sources of convective forcing in the record El Niño and central-based warm pool.

 

 

An examination of the convective forcing via equatorial precipitation anomalies throughout the eastern and Pacific basin yields a similar story to that of the velocity potential. The axis of heaviest convection is located furthered east in December when El Nino, at 155 degrees longitude, while El Niño is most prominent in that battle for convective proxy.

 

 

It shifts westward to approximately 163 degrees longitude in January, as the central mode becomes a bit more dominant around the midway point of the season.

 

And continues to hold fairly steady at around 162-163 degrees longitude throughout the month of February.

 

This 155-160 mean position of the sheared convective axis as a result of the two competing centers is consistent with both the 1982-1983 (left) analog, as well as the basin-wide composite (right).

 

 

The 1982-1983 season is rapidly distinguishing itself from other analogs due to its' similarities to a unique set of circumstances that play a crucial role in dictating exactly how this winter season ultimately evolves. These factors include the ultimate peak intensity of El Niño, considerations that impact the behavior of the polar domain, such as the solar cycle and state of the stratosphere, in addition to the precise evolution or El Niño that will be so critical to its' interaction with the central Pacific warm pool that will dictate how convective forcing influences our sensible weather.