2025-2026 ENSO

[GaWx]

12Z EPS held into the cold partially because of this:

[stadiumwave]

MJO Phases 7 & 8 & both really good as you move into DEC. 

Phase 6 is good in DEC until 2nd half of DEC. 

Phase 7 & 8 gets better each week as you progress into DEC. Phase 7 starts getting worse as you get into JAN. 

 

https://www.atmos.albany.edu/facstaff/roundy/waves/rmmcyc/index200reg.html

 

[GaWx]

1. EW 12/15-21: large change in just 3 days: will it hold?

11/25 run:

 

11/28 run:

——————

2. EW 12/8-14: huge change in just 3 days: will it hold?

11/25 run:

 

11/28 run:

 

—————

3. EW 12/1-7: huge change in just 3 days

11/25 run:

 

11/28 run:

—————-

-NYC has cooled from +1F to -4F for the 3 week period in just 3 days.

-They now have NYC at -3F for Dec as a whole, which is ~36-37F. 
Similar cold ENSO Decs were in 1954, 1964, 1966, 1975, 1981, 1988, and 2007.

 

[EastonSN+]

59 minutes ago, GaWx said:

1. EW 12/15-21: large change in just 3 days: will it hold?

11/25 run:

 

11/28 run:

——————

2. EW 12/8-14: huge change in just 3 days: will it hold?

11/25 run:

 

11/28 run:

 

—————

3. EW 12/1-7: huge change in just 3 days

11/25 run:

 

11/28 run:

—————-

-NYC has cooled from +1F to -4F for the 3 week period in just 3 days.

-They now have NYC at -3F for Dec as a whole, which is ~36-37F. 
Similar cold ENSO Decs were in 1954, 1964, 1966, 1975, 1981, 1988, and 2007.

 

Thanks for this. The only good snowfall winter on the list for CPK is 64/65. 

[MJO812]

Looping in 8. Insane. 

[snowman19]

The EPS and and GEPS caved to the GEFS on the +EPO/Alaskan vortex by the 2nd week of December, but they go +PNA/-NAO so it keeps the east under a trough
 

GEFS:  https://www.pivotalweather.com/model.php?m=gfs&p=500h_anom&rh=2025112900&fh=288&r=na&dpdt=&mc=&pwplus=1

GEPS, EPS: 

 

[GaWx]

Back down to neutral NAO/AO week 2 similar to 2 days ago:

[snowman19]

@donsutherland1 Out of curiosity, do you have any temp/precip composites for +EPO, +PNA, -AO, -NAO Decembers?

[GaWx]

MJO from today’s 2 week runs: both now have 11+ day long phase 8s, longest since Feb 2010 and longest Dec since 1975. Lots of potential in 1st half of Dec and beyond!
 

GEFS is all in 8 12/3-13 vs yesterday’s 7 for same period:

EPS is same as yesterday:

 

[mitchnick]

Yesterday's PV forecast has it impotent thru early January again.

[MJO812]

38 minutes ago, snowman19 said:

@donsutherland1 Out of curiosity, do you have any temp/precip composites for +EPO, +PNA, -AO, -NAO Decembers?

The EPS is starting to pick up on the negative NAO.

[donsutherland1]

1 hour ago, snowman19 said:

@donsutherland1 Out of curiosity, do you have any temp/precip composites for +EPO, +PNA, -AO, -NAO Decembers?

I will check when I get home this evening.

[40/70 Benchmark]

2 hours ago, snowman19 said:

The EPS and and GEPS caved to the GEFS on the +EPO/Alaskan vortex by the 2nd week of December, but they go +PNA/-NAO so it keeps the east under a trough
 

GEFS:  https://www.pivotalweather.com/model.php?m=gfs&p=500h_anom&rh=2025112900&fh=288&r=na&dpdt=&mc=&pwplus=1

GEPS, EPS: 

 

I probably rushed the PV recovery, which I can live with...the bigger deal is getting the Pacific trough transition correct.

[Stormchaserchuck1]

13 minutes ago, 40/70 Benchmark said:

I probably rushed the PV recovery, which I can live with...the bigger deal is getting the Pacific trough transition correct.

You going to get 3"? Glad I didn't bet you. The strong -PNA/+NAO being modeled didn't really happen. 

[Stormchaserchuck1]

The +EPO and cold probably isn't going to happen like that.. it's going to be one or another. If the negative 500mb over Alaska holds in the next few days, models will probably trend warmer in the CONUS. CPC yesterday put out a cold 3-4 week forecast though, with above average precip

[40/70 Benchmark]

5 minutes ago, Stormchaserchuck1 said:

You going to get 3"? Glad I didn't bet you. The strong -PNA/+NAO being modeled didn't really happen. 

I think so...which is why I wanted you to bet. I was very confident in a fast start to the month based on my analogs.

[Stormchaserchuck1]

4 minutes ago, 40/70 Benchmark said:

I think so...which is why I wanted you to bet. I was very confident in a fast start to the month based on my analogs.

I'm liking the cold tendency (-AO tendency) this cold season. Something like 97-98 and 01-02 are the farthest thing from right now. Notice how the modeled 500mb maps have more cold than warm anomalies in the N. Hemisphere.. we haven't seen that in like 10 years. When I researched snowfall in Winter the N. Hemisphere negative 500mb (general) was the strongest thing preceding. I'm trepidacious about an above average snowfall Winter down here, but we do have a better pattern coming compared to the last 10 years imo. Anyway, good job on your analog outlook. 

[leo2000]

28 minutes ago, Stormchaserchuck1 said:

The +EPO and cold probably isn't going to happen like that.. it's going to be one or another. If the negative 500mb over Alaska holds in the next few days, models will probably trend warmer in the CONUS. CPC yesterday put out a cold 3-4 week forecast though, with above average precip

I don't buy the +EPO with MJO going in phase 8 along with the weak polar vortex. I do think a +PNA is coming.