2025-2026 ENSO

[EasternLI]

Hmm, this is an interesting chart depicted by last night's eps cluster analysis. Not for whatever it may be depicting in anyone's backyard. The leading cluster in the day 11-15 range is this one. 

That progression of the troposphere gets really close to something resembling EOF2 from the following paper. With the +NAO and Scandinavian block. The progression leading to it is even pretty close to what is depicted in the paper. The Scandinavian Greenland dipole. Worth keeping an eye out for that phenomenon in future runs. As it's not something that's well modeled in advance. But a depiction of something like that on a prominent piece of guidance is interesting. 

Representation of the Scandinavia–Greenland pattern and its relationship with the polar vortex in S2S forecast models

https://rmets.onlinelibrary.wiley.com/doi/full/10.1002/qj.3892

From the abstract:

"The strength of the stratospheric polar vortex is a key contributor to subseasonal prediction during boreal winter. Anomalously weak polar vortex events can be induced by enhanced vertically propagating Rossby waves from the troposphere, driven by blocking and wave breaking. Here, we analyse a tropospheric pattern—the Scandinavia–Greenland (S–G) pattern—associated with both processes. The S–G pattern is defined as the second empirical orthogonal function (EOF) of mean sea-level pressure in the northeast Atlantic. The first EOF is a zonal pattern resembling the North Atlantic Oscillation. We show that the S–G pattern is associated with a transient amplification of planetary wavenumber 2 and meridional eddy heat flux, followed by the onset of a weakened polar vortex, which persists for the next two months."

[snowman19]

@40/70 Benchmark Mark Moregarbage’s wishcast of a major SSWE, full wind reversal, a SPV split, MJO phase 8, arctic cold death and KU blizzards up the east coast by Christmas week looks like it’s going to work out superbly!! 

[brooklynwx99]

you know, some of you keep giving that guy a platform by breathlessly posting about him. we know he sucks

[kazimirkai]

On 12/10/2025 at 9:18 AM, Terpeast said:

As I said in the MA forum yesterday, it won’t take much to shift that wpac warm pool slightly east to favor MJO 7-8 instead of 4-6. MJO 7 has sometimes shown to be a precursor to our biggest storms. 

And while the warm up is getting more aggressive on the models, my overall thoughts have not changed about 1) Neg WPO, 2) cold air source in Canada, 2) MJO waves into 7 and 8, and 4) increased chance of blocking due to stratosphere activity. These will increase the likelihood of a cold January moreso than a warm one.

I mean the MJO signal isn't progged to project much on to the midlat pattern for the foreseeable future beyond day 21 so I'm a little doubtful of it's predictive relevance in this case. 

[kazimirkai]

2 hours ago, EasternLI said:

Hmm, this is an interesting chart depicted by last night's eps cluster analysis. Not for whatever it may be depicting in anyone's backyard. The leading cluster in the day 11-15 range is this one. 

That progression of the troposphere gets really close to something resembling EOF2 from the following paper. With the +NAO and Scandinavian block. The progression leading to it is even pretty close to what is depicted in the paper. The Scandinavian Greenland dipole. Worth keeping an eye out for that phenomenon in future runs. As it's not something that's well modeled in advance. But a depiction of something like that on a prominent piece of guidance is interesting. 

Representation of the Scandinavia–Greenland pattern and its relationship with the polar vortex in S2S forecast models

https://rmets.onlinelibrary.wiley.com/doi/full/10.1002/qj.3892

From the abstract:

"The strength of the stratospheric polar vortex is a key contributor to subseasonal prediction during boreal winter. Anomalously weak polar vortex events can be induced by enhanced vertically propagating Rossby waves from the troposphere, driven by blocking and wave breaking. Here, we analyse a tropospheric pattern—the Scandinavia–Greenland (S–G) pattern—associated with both processes. The S–G pattern is defined as the second empirical orthogonal function (EOF) of mean sea-level pressure in the northeast Atlantic. The first EOF is a zonal pattern resembling the North Atlantic Oscillation. We show that the S–G pattern is associated with a transient amplification of planetary wavenumber 2 and meridional eddy heat flux, followed by the onset of a weakened polar vortex, which persists for the next two months."

Idk bout the two months but the current state would suggest some effects in early January which are reflected in extended gefs guidance

[MJO812]

Im not sure if we gonna see a big warmup. So much cold air up north. Looks like a gradient pattern to me .

[EasternLI]

16 minutes ago, kazimirkai said:

Idk bout the two months but the current state would suggest some effects in early January which are reflected in extended gefs guidance

Well sure, a couple things about that though. I've seen those charts change very rapidly in the past for one. As they start picking up on any specific tropospheric pattern that are the drivers of said events. Which models aren't great with at extended leads as we all know. Or even 5 days for that matter . Also that chart is from yesterday's weekly run. I didn't see anything resembling what I posted about on any of the runs yesterday. This was something new today in the 00z eps members. Lastly, I didn't call for anything to happen. That was just perfect opportunity to bring it up as it's a good illustration. Plus seeing that within the 00z eps members is a little interesting. 

[GaWx]

17 minutes ago, MJO812 said:

Im not sure if we gonna see a big warmup. So much cold air up north. Looks like a gradient pattern to me .

The Euro Weeklies suggest the most intense and persistent torching will actually be concentrated well to the W and SW of the E coast. So, whereas a big warmup vs the current very cold pattern is coming on all models, that big warmup in the E US appears to take it to only moderately warmer than normal instead of downright torchy when averaged out.

[40/70 Benchmark]

1 hour ago, snowman19 said:

@40/70 Benchmark Mark Moregarbage’s wishcast of a major SSWE, full wind reversal, a SPV split, MJO phase 8, arctic cold death and KU blizzards up the east coast by Christmas week looks like it’s going to work out superbly!! 

Waste of bandwidth.

[GaWx]

 Natural gas is down still another 3% on the day, which brings the total drop since the peak of 8 days ago to a very steep 25% on an anticipated much warmer E US pattern (though maybe not to a torch in the means as I stated in my prior post) starting mid to late next week and continuing for the foreseeable future! At least that’s some good news for future heating bills.

@Stormchaserchuck1

[JenkinsJinkies]

1 hour ago, MJO812 said:

Im not sure if we gonna see a big warmup. So much cold air up north. Looks like a gradient pattern to me .

I mean highs in the 50s are still above average.

[schoeppeya]

True kiss of death on a return to colder pattern is the cold air in Canada getting washed out, dont see any signs as of now. 

[GaWx]

 Today’s GEFS PNA forecast is the most negative for this Dec that I can recall:

 

 This implies the realistic chance for a sub -1 Dec PNA. Whereas that’s bad news for those wanting E US cold in the 2nd half of Dec in the MidAtlantic/OH Valley south, it isn’t necessarily bad news for January prospects. That’s because in the vast majority of cases for -ENSO, the PNA in January rose sharply from Dec:

 

PNA Dec/Jan for -ENSO for strongly -PNA in Dec

- 1955-6: -2.1/-1.3 (rose 0.8)

- 1961-2: -1.2/-0.1 (rose 1.1)

- 1964-5: -1.7/-0.2 (rose 1.5)

- 1971-2: -1.5/-1.4 (rose 0.1)

- 1984-5: -1.6/+1.6 (rose 3.2)

- 1996-7: -1.2/+0.6 (rose 1.8)

- 2008-9: -1.4/+0.6 (rose 2.0)

- 2010-1: -1.8/+1.3 (rose 3.1)

- 2012-3: -1.0/+0.6 (rose 1.6)

- 2013-4: -0.9/+1.0 (rose 1.9)

- 2021-2: -1.6/+1.0 (rose 2.6)

So, average PNA rise Dec to Jan for these was a whopping 1.8!

Dec temperature anomalies: coldest N Rockies to N Plains/mild much of SE 1/3:

 

Jan temp. anomalies: coldest shifts 1,000 miles SE and warmth gone

 

https://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/norm.pna.monthly.b5001.current.ascii.table

[Maestrobjwa]

So...how's the PDO looking?

[GaWx]

Just now, Maestrobjwa said:

So...how's the PDO looking?

WCS: Pretty steady for now but still within a longer term (6 month) rise:

[MJO812]

56 minutes ago, schoeppeya said:

True kiss of death on a return to colder pattern is the cold air in Canada getting washed out, dont see any signs as of now. 

Thats why I think the warm pattern will be brief and somewhat muted. 

[TheClimateChanger]

2 hours ago, GaWx said:

 Natural gas is down still another 3% on the day, which brings the total drop since the peak of 8 days ago to a very steep 25% on an anticipated much warmer E US pattern (though maybe not to a torch in the means as I stated in my prior post) starting mid to late next week and continuing for the foreseeable future! At least that’s some good news for future heating bills.

@Stormchaserchuck1

 

[Maestrobjwa]

10 minutes ago, GaWx said:

WCS: Pretty steady for now but still within a longer term (6 month) rise:

Thanks! Where do you find that? Been interested in the PDO because of how much the negative state screwed with snow chances the last decade.

[GaWx]

3 minutes ago, Maestrobjwa said:

Thanks! Where do you find that? Been interested in the PDO because of how much the negative state screwed with snow chances the last decade.

https://s2s.worldclimateservice.com/climatepanel/
 

Then click on 2nd map on right.

[GaWx]

12 minutes ago, TheClimateChanger said:

 

NG bulls want the opposite of this EPS HDD trajectory (see left graph): the cold part through 12/15 was dialed in to prices many days ago:

[LakePaste25]

Classic CAD setup which denies the coast of the torch. So despite it being warm just about everywhere else, we’ll constantly hear about how it’s “not a torch” because the most important cities in America will be cooler.