2026-2027 Record-breaking El Nino

[BlizzardWx]

1 hour ago, Stormchaserchuck1 said:

September has weak ENSO correlations, historically. It really picks up in October. 

I suppose that will be the question this fall, when this actually happens. It's probably going to be gradual as baroclinity increases, and my guess would be not much change from now until the back half of September. Could be pretty nasty in my area until then if we stay stuck under the heat dome. 

[Jebman]

3 hours ago, so_whats_happening said:

The only noticeable thing is the increase in moisture across my region specifically, still not enough to break the drought fully but working on it. The Caribbean has exceptional shear right now which is pretty typical of Nino (they are also below 30N so more in tune with what I had stated in my last post. There is quite an abundance of shear in that region that even areas of the East Pacific are being affected by this from about southern Mexico to Panama. Here are the 500mb patterns for MJJ leading into the strong to super Nino category based on RONI (since this is what we are using now).

https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso/roni/

I was reluctant to use 2023-24 since in RONI terms was only a moderate Nino (borderline strong) and comparing it to this year so far. There are some similarities this year to those past years in the southern hemisphere but overall the northern hemisphere seems to be opposite.

Thanks, so_whats_happening !

[PhiEaglesfan712]

5 hours ago, GaWx said:

Here’s the mean of the 9 Decembers preceding these very cold Nino Febs: like night and day! Look familiar?

Some years are missing, like 1995 and 2007. December 1994 and 2006 were very warm (actually the November-January period was near record warm), while February 1995 and 2007 were the outlier cold months.

[EasternLI]

Another curious detail about this year. Decided to look at the AO data for those other strong and super nino's. In the Jun-Jul period it looks like they all average negative for that period. All of them. This year it was positive. Not sure what that ultimately means but thought it was interesting. 

[EasternLI]

Top of the scale WWB on the 00z EPS. 

[GaWx]

1 hour ago, PhiEaglesfan712 said:

Some years are missing, like 1995 and 2007. December 1994 and 2006 were very warm (actually the November-January period was near record warm), while February 1995 and 2007 were the outlier cold months.

Thank you for adding Feb of 1995 and especially 2007 to the list. Indeed, two more cold Febs and they both had warm Decs! So, the idea continues to be that a warm Dec, which is expected especially up north and especially what @snowman19has emphasized and which El Niño climo favors, has little to no bearing on how cold Feb could be. That imho tells me the best way to look toward this winter, looking at its prospects month to month. Models and analogs are emphasizing the prospect for a big range from warm start to cold end.

[bluewave]

15 hours ago, Stormchaserchuck1 said:

Yeah, this Fall/Winter will be interesting to see if NPH trough develops. It hasn't really happened since 15-16. +SOI correlation was a match the last 2 Summers as well. 

Yeah, October has been a pretty good indication of the Aleutian low strength for the winter since 1997 during super El Niño.

Notice how large an area in the NEPAC during October 1997 was occupied by the Aleutian low. It actually had multiple centers. One area  NW of Hawaii and the other over the EPO and PNA regions.

The Southeast El Niño trough was already beginning to become established also.

That winter went on to have one of the strongest and largest Aleutian low areas of all-time.

In October 2015 and 2023 the Aleutian low was confined to a much smaller space in the NEPAC. Both of theses winters had smaller and more displaced Aleutian low locations than 1997-1998.

This matches the 500 mb ridges becoming stronger and more expansive since 2015-2016 and the troughs becoming weaker relative to earlier years.

 

 

 

[GaWx]

Initial WxBell Nov ‘26- Mar ‘27 forecast looks very reasonable although I’d like to see the month to month so as to see the expected large variability from early to late as I’ve just been posting about although they did say this:

The bottom line is the colder part of the winter is expected to be later, rather than in December.

Temps:

Snowfall:

[jconsor]

8 hours ago, so_whats_happening said:

It is also very interesting to see the MJO just stuck in Phase 6 for nearly a month (with the forecast through the 25th).

https://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/clivar_wh.shtml

Looking back at 97-98 we were null to even having a La Nina-esque lean to the MJO through summer, I get it less influential in the summer.

https://www.bom.gov.au/climate/mjo/#tabs=Monitoring

Unfortunately with the cuts to data I can not find reanalysis of VP to prior time periods to match with current times, since current times are not being updated.

You can find VP anomaly from 1940s to present from JMA 3Q reanalysis here: 
https://ds.data.jma.go.jp/gmd/tcc/tcc/products/clisys/figures/db_hist_jun_tcc.html (10 day means)
https://ds.data.jma.go.jp/gmd/tcc/tcc/products/clisys/figures/db_hist_mon_tcc.html (monthly means)

In the menu on upper left under "Field", click on Tropics.
Then under Element, click 200 hPa Velocity Potential.

[michsnowfreak]

6 hours ago, Stormchaserchuck1 said:

September has weak ENSO correlations, historically. It really picks up in October. 

All this concentration on Winter but Fall comes first. Fall is one of my favorite times of the year. October in MI is amazing so I'm hoping it is mostly dry, cool and sunny. 

[donsutherland1]

1 hour ago, GaWx said:

Initial WxBell Nov ‘26- Mar ‘27 forecast looks very reasonable although I’d like to see the month to month so as to see the expected large variability from early to late as I’ve just been posting about although they did say this:

The bottom line is the colder part of the winter is expected to be later, rather than in December.

Temps:

Snowfall:

This seems realistic given what is fairly likely (robust and energetic subtropical jet that brings above to perhaps much above normal precipitation to the southern tier). It seems that the initial outlook discounted the 2009-10 analog (as it should). Fall seems more uncertain, as one is dealing both with a lot of variables and the seasonal transition.

[GaWx]

 There’s a decent chance for a record breaking long phase 6 this month. It started in phase 6 on Aug. 3rd:

 

 The latest GEFS, one of the more reliable for the MJO in the WPAC, has phase 6 through the entire run, Aug 26th, except it has it on the border of phase 5 Aug 18-20th:

 

 The EPS has it in phase 6 through 8/23:

 

  These are the longest phase 6 periods on record (back to late 1974):

6/13-30/1984 18 days

7/28-8/18/1984 22

10/6-20/1988 15

7/15-8/4/1996 21

2/25-3/10/1997 14

11/16-12/1/1998 16

7/19-8/1/2018 14

10/13-31/2022 19

1/5-21/2026 17

 

 So, the longest phase 6 is currently the 22 days of late July-Aug of 1984 with the 2nd longest of 21 days mid July-early Aug 1996 (both near same time of year). The GEFS is suggesting the current one could reach 24+ days while the EPS has it ending up at 21 days.

[40/70 Benchmark]

10 hours ago, Stormchaserchuck1 said:

^QBO data only goes back to 1979, but add that and Dec is even warmer! I'm really curious to see what this Dec will look like. 

I have QBO data to 1948 at the page I use.

[40/70 Benchmark]

10 hours ago, so_whats_happening said:

https://psl.noaa.gov/data/correlation/qbo.data

goes back to 1948 monthly at just 30mb but was done being updated with a lot of other things back at the end of February 2026.

Also have this pdf from awhile back again unfortunately have not seen this updated in a long time

https://www.geo.fu-berlin.de/met/ag/strat/produkte/qbo/qbo_wind_pdf.pdf

Updated site for ^^^

https://www.atmohub.kit.edu/english/807.php

50mb to 1948, too.

https://psl.noaa.gov/data/correlation/qbo.50mb.data

[40/70 Benchmark]

1 hour ago, donsutherland1 said:

This seems realistic given what is fairly likely (robust and energetic subtropical jet that brings above to perhaps much above normal precipitation to the southern tier). It seems that the initial outlook discounted the 2009-10 analog (as it should). Fall seems more uncertain, as one is dealing both with a lot of variables and the seasonal transition.

I think 2010 is a perfectly viable analog for the second half....there seems to be this misconception that you can't include an analog in the composite unless you feel like the coming season will be a replica of it. Good luck operating like that because it's a pretty exclusive methodology. 

[40/70 Benchmark]

4 hours ago, EasternLI said:

Another curious detail about this year. Decided to look at the AO data for those other strong and super nino's. In the Jun-Jul period it looks like they all average negative for that period. All of them. This year it was positive. Not sure what that ultimately means but thought it was interesting. 

It implies a negative AO winter in the mean for the coming season.

[donsutherland1]

22 minutes ago, 40/70 Benchmark said:

I think 2010 is a perfectly viable analog for the second half....there seems to be this misconception that you can't include an analog in the composite unless you feel like the coming season will be a replica of it. Good luck operating like that because it's a pretty exclusive methodology. 

I don't disagree that it could be viable, especially if strong blocking were to develop. I was just referring to the entire period. I think a back-loaded scenario is plausible. So is a one notable storm-type idea.

[40/70 Benchmark]

1 minute ago, donsutherland1 said:

I don't disagree that it could be viable, especially if strong blocking were to develop. I was just referring to the entire period. I think a back-loaded scenario is plausible. So is a one notable storm-type idea.

Yea, I get what you were saying...no way will December be similar. I am sure to explain how I derive my seasonal composite members before introducing the map, in addition to also giving a composite list for each individual month, so I agree that a measure of preemptive context is important.

[40/70 Benchmark]

I like that the RON/ONI delta seems to be closing a hair (.5 to .4)...I mentioned back in my blog earlier this summer that this will be key to salvaging a decent second half...I hedged towards a 2015-like middle ground (think 1997 canonical /2023 MC opposite ends of spectrum), and still like that....at least.

[40/70 Benchmark]

I bet we see that delta continue to slowly shrink. 1982 actually ended up with a RONI that was higher than the ONI, which is likely why it's the only intense El Niño to average slightly -WPO. I don't expect us to get that far this year, as the ONI will remain somewhat higher, but I do think that the absolute RONI value will get higher.