2025-2026 ENSO

[michsnowfreak]

10 hours ago, mitchnick said:

New Cansips run looks very similar to last couple months with normal to BN 40N into Canada fwiw. Pretty consistent ridging over/near Alaska and poleward with SE ridging around until February. 

It has remained remarkably consistent for months now with its winter outlook.

[GaWx]

 AAM finally going - (Ninaish):

[snowman19]

 AAM finally going - (Ninaish):

I’m expecting a -AAM dominant fall

[40/70 Benchmark]

17 hours ago, michsnowfreak said:

It has remained remarkably consistent for months now with its winter outlook.

"Well, in this new, warmer climate, guidance has consistently underestimated the southeast ridge, time of the MJO spent in (insert undesirable phase) and (insert undesired weather)".

[donsutherland1]

The CANSIPS (cool) and CFSv2 (warm) are at odds regarding the fall outcome in the central U.S. It will be interesting to see what the ECMWF seasonal forecast shows when it comes out in a few days.

[raindancewx]

The lowest ACE La Ninas tend to see severe cold dumps / cold waves into the West in Nov-Feb. For whatever reason the trend doesn't hold in the cold neutrals. The recent average ACE in hurricane seasons immediately before a La Nina winter is something like 160. Canadian doesn't really have a La Nina. Inactive September in La Nina can often precede a severely cold January nationally too if you look.

My assumption is this entire setup will show up, shoved south in the winter. Unlikely to be the dominant pattern. But as a recurring minor setup. The setup moved far enough south would be +WPO with a +PNA - that's a pretty wet pattern out here in the Fall/Spring if it is in place during those times. Not as good for winter locally. Parts of the look show similarities to the quite hurricane seasons of 2013 and 2022. September 2013 is wettest on record locally, with Feb-Apr 2023 seeing severe cold for the time. We had a low of 21F here in April 2023, all time record for April here is like 18F. If you push everything south its a good pattern Plains like 2013, if you push it southeast, good pattern west like 2022. The high south of South America would be by Greenland and the big low SE of Australia would move to the Western US with the low over Kamchatka and the high off southeast asia instead of east of Japan.

This is the southeast movement solution (Feb 1-Apr 7 2023)

[40/70 Benchmark]

18 minutes ago, raindancewx said:

This is the southeast movement solution (Feb 1-Apr 7 2023)

 

[Stormchaserchuck1]

I never got the ACE/Winter relationship. It seems a little dreamy. A caveat is there are probably macro factors that correlate the two variables. Last Winter we did have colder weather after a high Atlantic ACE, with some (although short timed) -NAO and -AO bouts. The top Winter analog years after high Atlantic ACE does have an unusually east-based -NAO Winter, but it could be because of not enough examples. I haven't heard of Winter cold coming after a low ACE season though, and I don't know that it will actually be a low ACE season.. the NAO/AO have been positive thus far, but long range models are trying to neutralize that going into mid-August. These positive AO periods the last 2 years have been complete shut down of Atlantic activity - but that's the macro variable, the +AO. It might be easier and a bit more accurate to run that variable forward. 

[snowman19]

The CANSIPS (cool) and CFSv2 (warm) are at odds regarding the fall outcome in the central U.S. It will be interesting to see what the ECMWF seasonal forecast shows when it comes out in a few days.

If we do indeed flip to a -AAM regime along with -PDO and -ENSO/Nina, the CANSIPS for fall (SON) makes no sense

[PhiEaglesfan712]

7 hours ago, Stormchaserchuck1 said:

I haven't heard of Winter cold coming after a low ACE season though, and I don't know that it will actually be a low ACE season..

2013-14 and 2014-15 came after low ACE seasons. Low ACE season is pretty much locked unless we get a Hurricane Andrew, and even then, we'll probably still finish below average in ACE. (1992 finished with 76 ACE despite having Hurricane Andrew.)

I feel like the hand has been dealt. The East Pacific is having a very active year, while the Atlantic has been very quiet. It's August now, and that's probably not going to suddenly shift gears at this point. (If the Atlantic was going to get active, we would have seen it by now. Even 2004 got started with Alex  late in July. We're already past that, and this season has been completely blank.) The question now is if the Atlantic will get that big storm (like Andrew in 1992) or if we're going to get shut out (like in 2013).

[snowman19]

[mention=564]Bluewave[/mention] Was your MJO fall indicator for winter September or October? So far, since spring the MJO waves have been very heavily favoring phases 5-6-7, but with nowhere near the record strength/amplitude we saw last year

[bluewave]

1 hour ago, snowman19 said:

[mention=564]Bluewave[/mention] Was your MJO fall indicator for winter September or October? So far, since spring the MJO waves have been very heavily favoring phases 5-6-7, but with nowhere near the record strength/amplitude we saw last year

It’s based on the peak MJO 5 amplitude in October during multiyear La Ninas. La Ninas with MJO 5 peaks over +2.70 in October had the stronger +PNA from December into January. But it usually only happens once during each multiyear La Niña. 

This most recent La Nina in 24-25 had the MJO 5 peak last October over +2.70. So the +PNA from December into January was at record levels for a La Nina. NOAA coined the phrase mismatch in their blog when La Ninas have strong +PNA patterns rather than -PNA.

The 20-21 to 22-23 multiyear La Ninas had the most amplified MJO 5 in October 20. So the strongest Dec-Jan +PNA during that 3 year La Niña occurred in 20-21. The other 2 La Nina’s were more -PNA. But there were still several +PNA intervals during this winters.

During the 16-17 to 17-18 two year La Niña the strongest MJO 5 in October occurred in 17. Dec-Jan 17-18 had a better +PNA than Dec-Jan 16 did.

So based on this pattern over the last decade, my guess is that the MJO 5 will be weaker this October than last year. But I want to wait for the actual verification to make that call for sure.

My early guess for next winter is that it will be warmer than last winter was with the PNA index less positive than last winter was. But since the snowfall was so low anyway, it wouldn’t take much for one snowstorm to potentially equal or exceed last winter around NYC Metro.

 

 

[GaWx]

6 hours ago, PhiEaglesfan712 said:

2013-14 and 2014-15 came after low ACE seasons. Low ACE season is pretty much locked unless we get a Hurricane Andrew, and even then, we'll probably still finish below average in ACE. (1992 finished with 76 ACE despite having Hurricane Andrew.)

I feel like the hand has been dealt. The East Pacific is having a very active year, while the Atlantic has been very quiet. It's August now, and that's probably not going to suddenly shift gears at this point. (If the Atlantic was going to get active, we would have seen it by now. Even 2004 got started with Alex  late in July. We're already past that, and this season has been completely blank.) The question now is if the Atlantic will get that big storm (like Andrew in 1992) or if we're going to get shut out (like in 2013).

 The jury is obviously far from a decision for the 2025 season as a whole. Yes, YTD NATL ACE has been very low (1.5 vs 1951-2024 avg of ~9) through this morning with it at 64th highest out of the last 75 seasons. And being that low this far into the season does increase the chance for a quiet rest of season somewhat, which I’d love to see for a change. And yes, there are two new areas in the EPAC that may develop this week. However:
 

1. The EPAC is currently still at only 28 ACE vs a normal of 47 meaning it’s now ranked at only 39 of the last 55 seasons.

2. We have weak La Ninalike conditions, which are typically conducive for an active rest of season.

3. The following other relatively quiet through now NATL seasons (under 5 ACE vs normal of 9) were active the rest of the season:

 

Season: Total season’s NATL ACE

1969: 148 and that was El Niño (don’t have EPAC pre-1971); only 1 storm as of now (not an H) with 17 others still to come and not til Aug 10th+

2017: 225 and EPAC was then way up at 74 (12/54); no H yet with 10 H/6 MH still to come Aug 7th+

2019: 132 and EPAC ACE was then up at 45; only 2 storms as of now with 16 more to come and not til Aug 20th+

1980: 148

1999: 176; only 1 storm through now (not an H) with 11 others to come and not til Aug 18th+ including 5 MH

2004: 227 and that was El Niño; only 2 storms through now with 13 more to come Aug 9th+ including 9H/6 MH

1998: 181 and EPAC was then up at 55 (14/54); only one storm as of now (not an H) with 13 more to come, including 10 H and not til Aug 19+

1955: 158 (don’t have EPAC pre-1971); only 2 storms through now (no H yet) with 9H/4 MH still to come

1967: 125 (don’t have EPAC pre-1971); only 1 storm as of now with 12 more to come and not til Aug 28+

 From this list: 1969, 2017, 2019, 2004, and 1998 should especially get one’s attention.

 

4. The Euro Weeklies, which overall did well last year with its several week out predictions, have been forecasting an active August for the last 5 days.

5. The various ensemble runs have been active both in the MDR as well as off of NC. The current TWO is already highlighting two areas.

6. The MJO is headed for phases 1 and 2, two often active phases during August.

————-

 In summary, whereas the very low ACE as of this morning is typically a slightly bearish indicator the rest of the season as a whole, my points 1-6, above, suggest that an active rest of the season is at the very least still a reasonable possibility and may actually still be favored.

[snowman19]

Enjoy this cooldown while we still can….looks like we are all geared up for the next round of heat/humidity by mid-August. Verbatim, this is easily 90’s and this signal has been showing up since the end of July

[George BM]

Fresh off the press. A new monthly record low for the PDO.

 

[KakashiHatake2000]

https://x.com/MikeMasco/status/1951616081518321994?
sorry im slowly figuring out how to embed things but now i figured it out

[snowman19]

Fresh off the press. A new monthly record low for the PDO.
 

This -PDO cycle has beat the 1940’s-1970’s severely negative cycle

[bluewave]

36 minutes ago, snowman19 said:

This -PDO cycle has beat the 1940’s-1970’s severely negative cycle

Yeah, being driven this time by record mid-latitude 500mb ridges warming the SST anomalies to +15 near Japan. 
 

 

[mitchnick]

Glad I don't live in Japan.

[mitchnick]

1 hour ago, snowman19 said:

Enjoy this cooldown while we still can….looks like we are all geared up for the next round of heat/humidity by mid-August. Verbatim, this is easily 90’s and this signal has been showing up since the end of July

 

Better here than northern and central Canada. 

[40/70 Benchmark]

16 hours ago, Stormchaserchuck1 said:

I never got the ACE/Winter relationship. It seems a little dreamy. A caveat is there are probably macro factors that correlate the two variables. Last Winter we did have colder weather after a high Atlantic ACE, with some (although short timed) -NAO and -AO bouts. The top Winter analog years after high Atlantic ACE does have an unusually east-based -NAO Winter, but it could be because of not enough examples. I haven't heard of Winter cold coming after a low ACE season though, and I don't know that it will actually be a low ACE season.. the NAO/AO have been positive thus far, but long range models are trying to neutralize that going into mid-August. These positive AO periods the last 2 years have been complete shut down of Atlantic activity - but that's the macro variable, the +AO. It might be easier and a bit more accurate to run that variable forward. 

Nor do we know that it will be a technical La Niña season, as the supposed ACE rules only apply to La Niña.

[roardog]

1 hour ago, 40/70 Benchmark said:

Nor do we know that it will be a technical La Niña season, as the supposed ACE rules only apply to La Niña.

Then on top of that, if the ONI ends up cold neutral but RONI is into Nina, does the ACE rule apply then? Neutral and weak are tough because there’s just so many competing influences on the pattern. 

[Maestrobjwa]

4 hours ago, snowman19 said:

This -PDO cycle has beat the 1940’s-1970’s severely negative cycle

My goodness that cycle lasted for 30 years?? So "decadal" isn't so much a literal decade but just however many decades it lasts? 

(I'm sure you would've loved it back then...lol Although the 60s were snowy for the east)

[KakashiHatake2000]

how long has this -pdo cycle last im guessing longer than the 30 year span of the 1940s-1970s