2025-2026 ENSO

[anthonymm]

40 minutes ago, MJO812 said:

Seriously. I dont know what people are seeing that the rest of us aren't seeing.   Things look good moving forward. 

 

 

 

Early Dec looks warm. One brief cold shot to close Thanksgiving and we get a raging -pna and SER after.

[stadiumwave]

54 minutes ago, 40/70 Benchmark said:

If you are ever in need of some rain for your parade, Bluewave has got you covered.

Locked & loaded 

[anthonymm]

20 minutes ago, Terpeast said:

All models are going strong into 7. The key will be whether it dies in 7, or pushes into 8 like the above plot does. I'm not convinced that will happen (and bluewave doesn't think it will), but if it does, it will be great for us.

no way mjo goes into phase 8. We're in a down cycle. We're paying for the previous snowy 20 year period.

[stadiumwave]

42 minutes ago, MJO812 said:

 

Can't you see how terrible that looks?? Its gotta be wrong until there's a run that has a deep trough in Cali & raging ridge in the East....then it's gospel. But do not worry, it is all objective with no subjectiveness at all.  

BTW, the posters I am messing with (you know who you are) I mean it all in total fun. You guys are actually really good posters!! 

[anthonymm]

1 minute ago, stadiumwave said:

 

Can't you see how terrible that looks?? Its gotta be wrong until there's a run that has a deep trough in Cali & raging ridge in the East....then it's gospel. But do not worry, it is all objective with no subjectiveness at all.  

-PNA is the default in niñas. I think we all agree here this winter will be predominantly a -PNA one.

[GaWx]

Today’s 2 week GEFS MJO progressed significantly more quickly vs yesterday’s run into phase 7!

Today’s 2 week GEFS (11/19) is 2 days faster making it into phase 7 vs yesterday’s run and is already halfway through phase 7 as of 12/3!

 

Yesterday’s 2 week GEFS (11/18) didn’t get to phase 7 til 12/1 vs today’s 11/29:

Yesterday’s extended GEFS (11/18) didn’t have it halfway through phase 7 til 12/7 meaning today’s 2 week GEFS gets to halfway through phase 7 four days faster (12/3) than yesterday’s extended GEFS (not til 12/7)!

 

[michsnowfreak]

23 minutes ago, anthonymm said:

Early Dec looks warm. One brief cold shot to close Thanksgiving and we get a raging -pna and SER after.

Warm for who, Florida?

[LakePaste25]

2 hours ago, bluewave said:

We may not get a clean translation of any of the specific MJO 7 composite to start December since the models are showing more of a split forcing pattern. Notice the forcing lingering near the Maritime Continent at the same time there is forcing over the Western Hemisphere. So the current forecast has more of blended look between competing influences. Forcing near the Maritime Continent tends to enhance the Southeast ridge and lead to a faster Pacific Jet. 

 

We saw this a few times last winter. Fast pac jet leads to systems undercutting the PNA ridge, causing energy to get buried in the southwest, thus, rolling over the ridge into the east. 

 

 

[GaWx]

6 minutes ago, michsnowfreak said:

Warm for who, Florida?

Latest (yesterday’s) Euro Weeklies for 12/1-7 fwiw shows it warmer than normal in much more than FL though we’ll see whether this cools off today considering the colder end of Nov (lots of model volatility currently):

[GaWx]

 IF the 11/18 bc version of the extended EPS were to be right, you couldn’t ask for a better position of the MJO in Dec/Jan: just outside the circle in phase 8 (and very slow moving making it last longer would be a big bonus) is about the coldest on average in the E US as it’s colder than strong phase 8 on average (though there’s always lots of variation of course): if you asked me to place it in a better place and speed of movement in Dec or Jan I couldn’t:

[SnowGoose69]

1 hour ago, MJO812 said:

Same can be said about the gefs also. Maybe the SSW is giving the models a hard time.

The EPS much like most recent winters is getting beaten by the GEPS/GEFS in that range in regards to that E Pac/AK pattern....the 00Z run is again trying to build a SER post D12 again.  I think part of what is happening is the Pac is still progressive so the EPS tries to develop these wild storms like Panhandle hooks and cutters and the flow just is not allowing for that type of activity to end up happening.  As a result, there is much less SER in the end.  Also the GEFS have backed away a bit from the -PNA magnitude the last 2 days on the ensembles after D10.

The most glaring bad news I see in last 2-3 days is the flow is still just screaming.  You can look at the last 3-4 GFS Op runs alone to see how we went from dumping cold into the W to the dump now despite going E does not make it significantly far into the Mid-South or SE because the progression of everything.  Until that problem goes away we ain't seeing any consistently stormy pattern for the NE or MA

[FPizz]

4 hours ago, BlizzardWx said:

A lot has changed in the last month. Waters have cooled east of Japan and warmed in the east Pacific, a trend likely to continue. The PDO by my calculations is closing in on -1, and should rise further with this pattern. The -IO has collapsed. With some decent cooling near the MC, hopefully limiting MJO 4-6 this winter. The +AMO is strengthening but with a tripole pattern. RONI remains below -1. Global temperature anomalies dropped another 0.1 C in the last month. 

PDO was -0.92 last update, IOD weakening as well.

[MJO812]

50 minutes ago, anthonymm said:

no way mjo goes into phase 8. We're in a down cycle. We're paying for the previous snowy 20 year period.

LOL stop posting 

[brooklynwx99]

24 minutes ago, LakePaste25 said:

We saw this a few times last winter. Fast pac jet leads to systems undercutting the PNA ridge, causing energy to get buried in the southwest, thus, rolling over the ridge into the east. 

 

 

that's transient. models have vastly underdone the cold spell near Thanksgiving already and whatever brief warmup occurs around the start of the month won't last long

[brooklynwx99]

like this is just a fail. the stronger Pacific jet actually helps in Ninas most of the time, not hurts

[GaWx]

43 minutes ago, GaWx said:

 IF the 11/18 bc version of the extended EPS were to be right, you couldn’t ask for a better position of the MJO in Dec/Jan: just outside the circle in phase 8 (and very slow moving making it last longer would be a big bonus) is about the coldest on average in the E US as it’s colder than strong phase 8 on average (though there’s always lots of variation of course): if you asked me to place it in a better place and speed of movement in Dec or Jan I couldn’t:

 More stuff related to weak to moderate Dec phase 8 having been the coldest Dec phase 8 MJO on average: Dec 9-18 of 1989 was frigid/~tied for the coldest Dec phase 8 in the E US since 1974 along with 5.5” of snow at Baltimore (2 events) and it was weak/near the circle and slow moving: also note that it stayed frigid through this very weak phase 1 and the moderate phase 2:

 

About tied with the frigid 1989 was the very cold 12/6-9/2002. Note that this phase 8 wasn’t too far outside of the circle (moderate phase 8):

 

 Temperatures are based on Baltimore as an E US proxy.

 

[kazimirkai]

4 hours ago, snowman19 said:

FWIW, Judah updated his SPV blog for anyone interested:
 

Lol what's nail-biting about it? Every single ensemble member supports it and about 90% are on board for a full reversal. Seems a bit clickbaity

[anthonymm]

2 minutes ago, kazimirkai said:

Lol what's nail-biting about it? Every single ensemble member supports it and about 90% are on board for a full reversal. Seems a bit clickbaity

There is a reason Judah is a well respected meteorologist. He doesn't jump on cold because he knows it's hard for us now. If you bet against sustained cold in winters in the mid atlantic/NE nowadays you'll be right 9 times out of 10.

[GaWx]

AAM forecast (CFS ensemble): big change for mid Dec vs forecast from two days earlier (warning: these are highly volatile on right side of graph):

11/18/25 AAM forecast: suggests it may go + (El Ninoish) in mid-Dec?!?

11/16/25 AAM forecast:

11/11/25 AAM forecast:

@snowman19

[kazimirkai]

3 minutes ago, anthonymm said:

There is a reason Judah is a well respected meteorologist. He doesn't jump on cold because he knows it's hard for us now. If you bet against sustained cold in winters in the mid atlantic/NE nowadays you'll be right 9 times out of 10.

I mean yeah, deriving the effect of an SSW is a much more complex problem, but no one's debating whether or not it will occur. That's what I find comical about this post. 

[Terpeast]

51 minutes ago, brooklynwx99 said:

like this is just a fail. the stronger Pacific jet actually helps in Ninas most of the time, not hurts

And imho it's not the speed of the pac jet, it's the placement of the strongest portion of the jet and it's exit region. If the jet is favored equatorward and its exit region is just south of the aleutians, we get ridging over AK and cold air flowing south into the CONUS towards the east.

[GaWx]

Natural gas is up 4.5% on colder model trends.

[donsutherland1]

The idea of an imminent SSW/MSW event is a high-confidence one. However, there is often a tendency to treat forecast developments (“SSW → PV split → EPO-/WPO-/AO-/PNA- → brutal NE weather”) as if it were an inevitable, linear, cause-and-effect chain. If such logic were reliable, forecasting accuracy at multi-week stages would be high. That isn't the case.

I personally believe that there will be an increase in wintry effects, especially from near mid-December into at least late December based on typical 1-3 week lags and the currently forecast teleconnection evolution.  That's my baseline thinking at present.

However, that thinking isn't cast in stone. Reality is messier. For example, not every SSW leads to a prolonged deep AO-. Not every AO- period results in severe cold and/or excessive snowfall. 

From this far out, model skill is poor to non-existent on critical synoptic factors e.g., future storm tracks, the emergence of North Pacific jet streaks, exact ridge-trough placement, etc. A bad pattern coupled with a well-timed phase can produce a big snowstorm; a great pattern but badly-timed phases or absence of shortwaves can result in a lack of snowfall. Seemingly favorable ensemble means can also disguise large differences among ensemble members.  Clusters can provide insight into some scenarios.

Here are the forecast 500 mb anomalies at 360 hours:

Here are the latest 500 mb and 1000 mb ECMWF clusters:

500 mb:

1000 mb:

For now, potential is on the table. But nothing is locked in, just yet, in terms of specific details.

[stadiumwave]

3 hours ago, anthonymm said:

-PNA is the default in niñas. I think we all agree here this winter will be predominantly a -PNA one.

 

So what was your guess last year during a La Nina dominated by +PNA? PDO was even more negative at this point last year. Could it be more -PNA? Yes! Is it a given? No! 

[GaWx]

1 hour ago, donsutherland1 said:

The idea of an imminent SSW/MSW event is a high-confidence one. However, there is often a tendency to treat forecast developments (“SSW → PV split → EPO-/WPO-/AO-/PNA- → brutal NE weather”) as if it were an inevitable, linear, cause-and-effect chain. If such logic were reliable, forecasting accuracy at multi-week stages would be high. That isn't the case.

I personally believe that there will be an increase in wintry effects, especially from near mid-December into at least late December based on typical 1-3 week lags and the currently forecast teleconnection evolution.  That's my baseline thinking at present.

However, that thinking isn't cast in stone. Reality is messier. For example, not every SSW leads to a prolonged deep AO-. Not every AO- period results in severe cold and/or excessive snowfall. 

From this far out, model skill is poor to non-existent on critical synoptic factors e.g., future storm tracks, the emergence of North Pacific jet streaks, exact ridge-trough placement, etc. A bad pattern coupled with a well-timed phase can produce a big snowstorm; a great pattern but badly-timed phases or absence of shortwaves can result in a lack of snowfall. Seemingly favorable ensemble means can also disguise large differences among ensemble members.  Clusters can provide insight into some scenarios.

Here are the forecast 500 mb anomalies at 360 hours:

Here are the latest 500 mb and 1000 mb ECMWF clusters:

500 mb:

1000 mb:

For now, potential is on the table. But nothing is locked in, just yet, in terms of specific details.

 Thanks Don,

 I see your point about the unpredictability of upcoming NE snow. Moreover, this thread isn’t strictly about NE snow (as you know). It’s of course also about NE and other areas’ temperatures, wintry precip in other areas, and many other things.

 Wintry precip, which is usually more variable/localized than the cold influence of Arctic airmasses, is thus often less predictable than temperatures. Therefore, regarding the potential lagged effects of an SSWE, I’m guessing that temperatures in the NE US as well as for other areas for whatever period would be less unpredictable than snowfall. From what I’ve learned, there’s a significantly better chance than normal for a multi week long period of cold domination in the E US usually starting 2-3+ weeks after an SSW. More often than not the cold will appear in the E US. Most likely that would naturally mean increased wintry precip in parts of the E US, but where is the question?

 Especially if there’s a decent sized sample, I do like to look back at specific cities’ stats (temps and wintry precip) to give me some idea of the potential, regardless.

[GaWx]

12Z ensemble means at H5 just after the cold shot at the end of Nov:

GEFS:

 

EPS: more amplified including much stronger SE ridge than GEFS:

 

We’ll see which verifies more closely. Lately, cold has had the edge.

[brooklynwx99]

3 minutes ago, GaWx said:

12Z ensemble means at H5 just after the cold shot at the end of Nov:

GEFS:

 

EPS: more amplified including much stronger SE ridge than GEFS:

 

We’ll see which verifies more closely. Lately, cold has had the edge.

the EPS is just a day or two slower. it gets to the same point with a -NAO developing thanks to Scandi ridging (which is typical of SSW events)

[brooklynwx99]

can pretty easily see the N ATL trough feeding back on the Scandi ridge, which then increases heights in the NAO region... this elongates and presses the TPV south