2026-2027 Record-breaking El Nino

[George BM]

25 minutes ago, mitchnick said:

Cansips on TT (not all products yet)

https://www.tropicaltidbits.com/analysis/models/?model=cansips&region=namer&pkg=z500a&runtime=2026100100&fh=0

At first glance on TT the Cansips have peak SST anomalies even warmer for Nov/Dec generally between 125-140W. Peak SSTAs are a little further east compared to last month but still pretty far west.

[so_whats_happening]

15 hours ago, OSUmetstud said:

This plot is not consistent with 2 m temperature being 2 C below the much older 1958 to 2002 climatology all summer. This area is all ocean/ice. 

This was from the temp website

https://ocean.dmi.dk/arctic/documentation/arctic_mean_temp_data_explanation_newest.pdf

I use 925mb specifically to not get temperature but more so to see the pattern associated to this region in specific thus I will continue to use 925mb as a better representation of what is going on. This was a retention year in that the overall atmospheric pattern was on the colder side. Unfortunately I don't think we will get fairly accurate measurements of the lowest 1000' or so in this region due to the complex nature involved with sea ice/ oceanic exchange issues with the lower atmsophere. You will read this within the first paragraph as to the issues involved. Another factor is the slushification that is taking place throws another wrench into getting an accurate surface reading.

2006 and 2013 were also solid retention years. The time period of roughly mid April to end of June will continue to be an  extremely important time to gauge how the melt season will go. 

There is a glaring difference when comparing ERA5 of 2013 to 2026 2m temps.

[mitchnick]

@40/70 Benchmark

Cansips D-M

[40/70 Benchmark]

48 minutes ago, mitchnick said:

@40/70 Benchmark

Cansips D-M

That looks best in December and gets progressively worse.

[mitchnick]

43 minutes ago, 40/70 Benchmark said:

That looks best in December and gets progressively worse.

Yes, but 500mb, temps and precip look ok. Check the winter thread in your forum.

[GaWx]

16 hours ago, GaWx said:

 As I said, I’ve been following model initializations of 2m at 80+ N. They were colder than climo most of late May-early Aug.

 Check out those of the Euro for yesterday: clearly solidly BN vs 1981-2010 for 80N+ on Sep 29th (associated with a storm)(they were also quite cold going back to Sep 23rd by the way), which may actually be cold enough to support the ~2C colder than the 1958-2002 mean shown on the newest DMI graph:

 

 Here’s the Euro forecast for Oct 2nd, which shows notable warming as the storm moves S into Siberia. This is why I’m expecting warming on the DMI graphs by then:

@so_whats_happening@OSUmetstud

Follow-up: As expected based on the model consensus having significantly warmer 2m maps on Sep 30th vs Sep 29th at 80N+, the DMI warmed notably yesterday (>1C) vs Sep 29th as it rose to the blue line (mean for 1958-2002). It should warm further tomorrow:

[bluewave]

Much different October El Niño pattern than we have seen in the past. The ridges are significantly further south than usual. One ridge east of Japan and another over the CONUS.

Similar to the pattern we have been seeing since last May. This stronger mid-latitude ridge is the same pattern driving the -PDO +AMO.

The strongest October El Niño ridge is typically in the EPO region of Alaska and NW Canada.

Also different from 1997 with the strong -WPO and 2015 with the -EPO. So a further south 500 mb ridge axis from those years also.

While the early September model forecast correctly got the ridge east of Japan, the ridge over North America is setting up much further south.

 

 

 

 

 

 

 

 

[mitchnick]

On 9/30/2026 at 8:43 AM, Stormchaserchuck1 said:

Yeah, October is the only month of the year that has an opposite correlation to DJFM NAO. I don't know if that's true given 250+ years of examples though. 

The +NAO strengthened thru mid October on all the ensembles last night fwiw.

[Stormchaserchuck1]

1 hour ago, mitchnick said:

The +NAO strengthened thru mid October on all the ensembles last night fwiw.

Maybe we'll get a surprise -nao for the Winter. It's felt cool lately, in Sept I had 3 straight nights in the 40s and an early end to Summer locally for the 3rd straight year. I keep saying, hard to believe it can't cool down 30 more degrees for the Winter. The last 2 years had these late Summer/Sept patterns too, and they got cold for the Winter. With the east-based Nino/-PDO completely unfavorable for cold, I keep thinking where would it come from? Maybe the NAO?

[Terpeast]

4 hours ago, bluewave said:

Much different October El Niño pattern than we have seen in the past. The ridges are significantly further south than usual. One ridge east of Japan and another over the CONUS.

Similar to the pattern we have been seeing since last May. This stronger mid-latitude ridge is the same pattern driving the -PDO +AMO.

The strongest October El Niño ridge is typically in the EPO region of Alaska and NW Canada.

Also different from 1997 with the strong -WPO and 2015 with the -EPO. So a further south 500 mb ridge axis from those years also.

While the early September model forecast correctly got the ridge east of Japan, the ridge over North America is setting up much further south.

 

 

 

 

 

 

 

 

It looks like the strong +AO pushed the mid-high lat ridges further south

[michsnowfreak]

40 minutes ago, Stormchaserchuck1 said:

Maybe we'll get a surprise -nao for the Winter. It's felt cool lately, in Sept I had 3 straight nights in the 40s and an early end to Summer locally for the 3rd straight year. I keep saying, hard to believe it can't cool down 30 more degrees for the Winter. The last 2 years had these late Summer/Sept patterns too, and they got cold for the Winter. With the east-based Nino/-PDO completely unfavorable for cold, I keep thinking where would it come from? Maybe the NAO?

The yearly max/min temp is always a fun one to watch. In 2026, the max at Detroit was 97F and the min -10F.

Even with a mild winter we will likely still go below zero. The avg temp for summer here is 72.3F and winter 28.4F, a difference of about 44F.

[FPizz]

33 minutes ago, michsnowfreak said:

The yearly max/min temp is always a fun one to watch. In 2026, the max at Detroit was 97F and the min -10F.

Even with a mild winter we will likely still go below zero. The avg temp for summer here is 72.3F and winter 28.4F, a difference of about 44F.

I always like that too.  This year 102.3 for my high and -5.4 for my low.  One of the larger spreads that I can remember.

[bluewave]

1 hour ago, Terpeast said:

It looks like the strong +AO pushed the mid-high lat ridges further south

There has been a deep upper low across the Arctic since the spring with record 500 mb ridging across the mid-latitudes.

So this looks like a continuation of the same theme. Both the AO and NAO have been mostly positive over this period.

Almost looks like some type of rebound following the strong winter blocking with the early SSW back in November.

The last time we had a +AO October with a super El Niño was 1972.