2026-2027 Record-breaking El Nino

[Stormchaserchuck1]

2 minutes ago, Wannabehippie said:

Snow everywhere, or just in the east?

Lower midwest too. El Nino STJ has long tracking moisture storms across the lower part of the country. 

[Stormchaserchuck1]

40 minutes ago, mitchnick said:

Definitely broad brushes it considering what has fallen imby, but it has me AN at least.

I'm not sure I understand your point? You think this year is different from the 2017-25 average because you had a localized thunderstorm? 

[MJO812]

1 hour ago, Stormchaserchuck1 said:

Green to neutral areas. At least relative to average. 

The 21-0 +1.11 monthly NAO streak means we will have to buck a strong trend though. 

This would be awesome. Blocking plus strong stj

 

[mitchnick]

27 minutes ago, Stormchaserchuck1 said:

I'm not sure I understand your point? You think this year is different from the 2017-25 average because you had a localized thunderstorm? 

I thought it was this year and was surprised it wasn't showing more than just a broad brush look.

[Stormchaserchuck1]

12 minutes ago, mitchnick said:

I thought it was this year and was surprised it wasn't showing more than just a broad brush look.

Oh, ok. Fwiw, I kind of saw it coming. 

 

[GaWx]

 Due to the extreme cold anomalies progged by the CFSv2, look how cold the progged CFSv2 March ‘27 SST anomalies are off the E coast and in the N Gulf! Some areas are -5C/-9F even vs the slightly colder 1984-2009 climo!

 

[Stormchaserchuck1]

^Just Fwiw, the last 2 years a few runs the CFS has shown -38F anomalies in the NW, US for the month of Dec both times. It didn't happen lol

[GaWx]

15 minutes ago, Stormchaserchuck1 said:

^Just Fwiw, the last 2 years on a few runs the CFS has shown -38F anomalies in the NW, US for Dec both times. It didn't happen lol

 It’s very likely overdone, which is why I say it is more like a dream. But IF it were to actually have an inkling of what’s to come, we could be in store for an exciting or possibly even fab Feb. It is essentially going for another Feb of 1958, one of the greatest Febs on record in the E US and this with Feb RONI way up at +1.84! The CFS RONI prog for Feb ‘27 is for a rapid collapse down to +1.5. So, is it likely? No. But is it doable? Yes.
 

[Stormchaserchuck1]

Dec-Jan ONI has higher correlation for Feb than Feb ONI. I don't disagree that El Nino's have been historically cold in Feb though. In fact, I would say the stronger, the greater the cold signal should be. 2018-2025 however was the most -PNA on record for Feb by almost +50%! I'd watch the PDO there. 

[so_whats_happening]

5 hours ago, EasternLI said:

Yeah, will be fascinating to see how the north Pacific responds through this event. Given the deep -PDO state of the atmosphere it is encountering. El nino is certainly ramping up. AAM about to take another step up from the upcoming MJO cycling and associated WWB. Getting impressive too with a forecast mean remaining above 3 SD. If we look at the world view. We can see the SH jet has been, and is forecast to continue to be very impressive. Along with El nino conditions really getting comfortable in the tropics now as of late. A little bit of El nino's influence appears to be trickling into the NH now as well. The forecast has that continuing also and increasingly so as we get towards the tail end of the month. So envision a slow take over, if you will. As we go through the fall. That's my guess. Will be interesting to see if that's how it plays out. I think that makes some sense given the underlying resistance in the Pacific. I personally doubt that resistance will ultimately be too much for this event. Not one of this magnitude, this one's a behemoth. But that is a battle worth watching in the north Pacific for sure. Would still love to see a recurving typhoon or 2 as well but there's time for that.

 

Yea we are still lacking quite a bit with the AAM into the northern hemisphere it just cuts off right 30N. So the Nino is thriving in the tropics to subtropics and the southern hemisphere but in the north it is struggling besides little bits and pieces that show up regionally.

https://atlas.niu.edu/gwo/

[GaWx]

1 hour ago, Stormchaserchuck1 said:

Dec-Jan ONI has higher correlation for Feb than Feb ONI. I don't disagree that El Nino's have been historically cold in Feb though. In fact, I would say the stronger, the greater the cold signal should be. 2018-2025 however was the most -PNA on record for Feb by almost +50%! I'd watch the PDO there. 

Thanks, Chuck. The quite cold E US Nino Febs I’m aware of are 2015, 2010, 2003, 1980, 1978, 1958, 1914, 1912, 1905, 1889, and 1885.

[so_whats_happening]

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.

[Nomz]

Hey y'all. Pretty new to long-range forecasting; had a couple random questions I couldn't get a good answer on:

When someone says a model is spitting out a peak of +4.5, for example, is that a single-day peak or a three-month average, as tracked by the NWS?

Are we generally discussing RONI or ONI, and which is more predictive? (Does it change with seasons?)

 

[GaWx]

5 minutes ago, Nomz said:

Hey y'all. Pretty new to long-range forecasting; had a random question I couldn't get a good answer on:

When someone says a model is spitting out a peak of +4.5, for example, is that a single-day peak or a three-month average, as tracked by the NWS?

 

It is usually either a 3 month or a 1 month avg.

[GaWx]

1 hour ago, GaWx said:

Thanks, Chuck. The quite cold E US Nino Febs I’m aware of are 2015, 2010, 2003, 1980, 1978, 1958, 1914, 1912, 1905, and 1885.

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

[Stormchaserchuck1]

^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. 

[Stormchaserchuck1]

50 minutes ago, Nomz said:

Are we generally discussing RONI or ONI, and which is more predictive? (Does it change with seasons?)

You can actually make your own custom index, factoring in global warming, which is about +0.2-3 for Nino 3.4. In other words, 0.0 neutral is now with global warming +0.2-3. The point of RONI is to even it out, so you can track mid latitude influences more, but there are a lot of extra guidelines with it I think that make it vary month-to-month. Just factoring in global warming skew is helpful for seeing what pure ENSO event is like. 

On the seasonal model forecasts, it usually shows the timeframe somewhere on the top of the map. It's usually 1 month, or 3-months. 

The CPC officially uses RONI: Climate Prediction Center - CPC adopts Relative Oceanic Niño Index (RONI) for reliable, responsive monitoring and tracking of ENSO

[so_whats_happening]

29 minutes 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. 

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

[Jebman]

2 hours ago, so_whats_happening said:

Yea we are still lacking quite a bit with the AAM into the northern hemisphere it just cuts off right 30N. So the Nino is thriving in the tropics to subtropics and the southern hemisphere but in the north it is struggling besides little bits and pieces that show up regionally.

https://atlas.niu.edu/gwo/

So it IS true we are seeing some influence from the Nino in the CONUS?

This link is interesting. https://atlas.niu.edu/gwo/

[Stormchaserchuck1]

22 minutes 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

Thanks! It looks like Dec 1957 was +7.4 QBO and Strong Nino

That's the only ONI>1.0, QBO>+6 analog pre-1979.

Dec 1970 Mod Nina, -17 QBO. Sometimes strong -PNA patterns have prevailed in Dec in Nina/-QBO. I could see how this would have been cold if not for the massive Aleutian block - notice the +150dm -NAO. (QBO is Strat - so more AO connection). 

[so_whats_happening]

17 minutes ago, Jebman said:

So it IS true we are seeing some influence from the Nino in the CONUS?

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.

[so_whats_happening]

8 minutes 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.

Looking through each year individually some years rhyme but you can't expect a 1:1 situation. 1991, 2015, 2023 stuck out the most as being similar to the northern hemisphere pattern we are currently seeing in the 3 month interval.

[Stormchaserchuck1]

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

[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.