2025-2026 ENSO

[Stormchaserchuck1]

15 minutes ago, GaWx said:

Can you do Solar min out to +24 months?

Solar Min is included in the maps. It's Max minus Min 

If the Solar is 500 (Min) and Max is 1500 (Max) and the average is 1000, Min is [-500] and Max is [+500]

The map is default positive phase, with both included, so for the Min, just flip the correlation coefficient around (+0.3 over Greenland vs -0.3). But it's also part of the same map. 

[Stormchaserchuck1]

To bluewave's point, here is the following Winter +1 year after a +PNA December

December +12 months

January +13 months

February +14 months

Somewhat of a signal there for warmer than average temps in the eastern 1/2. I didn't sort it out by negative ENSO, but the general gives you a lot more data points. It's on ok signal (ENSO usually changes state the year after a relative PNA Winter, which I will say again is interesting. It's counter-intuitive)

 

[GaWx]

24 minutes ago, Stormchaserchuck1 said:

Solar Min is included in the maps. It's Max minus Min 

If the Solar is 500 (Min) and Max is 1500 (Max) and the average is 1000, Min is [-500] and Max is [+500]

The map is default positive phase, with both included, so for the Min, just flip the correlation coefficient around (+0.3 over Greenland vs -0.3). But it's also part of the same map. 

Thanks.
1) So, for the 6 years, is this correct going from the most -NAO to the most +NAO?

min+2

min +1

min

max

max +1

max +2

 

2) It’s too bad we can’t see the other 5 years of the 11 year average cycle. But with cycles’ length differing cycle to cycle as opposed to always being 11 yrs, perhaps it would be less useful to go out 3-5 years from max.

[Stormchaserchuck1]

7 minutes ago, GaWx said:

Thanks.
1) So, for the 6 years, is this correct going from the most -NAO to the most +NAO?

min+2

min +1

min

max

max +1

max +2

 

2) It’s too bad we can’t see the other 5 years of the 11 year average cycle. But with cycles’ length differing cycle to cycle as opposed to always being 11 yrs, perhaps it would be less useful to go out 3-5 years from max.

I think you get it. If Min = -NAO = +2. If Max = +NAO = +2.  If Min = +NAO = -2, If Max =+NAO = +2, so the 2nd set would be "0", and the first set "+4". 

It's too bad it doesn't go out further. I've tried several times, hoping they would update. It's a 73-year base period, so there is not that much data cut off going out +3-4 years. To do the full 11 years, it would have to be manual, but you can see what NAO state is favored 1-2 years before a Solar Max/Min event at least (weaker overall correlation)

[GaWx]

2 minutes ago, Stormchaserchuck1 said:

I think you get it. If Min = -NAO = +2. If Max = +NAO = +2.  If Min = +NAO = -2, If Max =+NAO = +2, so the 2nd set would be "0", and the first set "+4". 

It's too bad it doesn't go out further. I've tried several times, hoping they would update. It's a 62-year base period, so there is not that much data cut off going out +3-4 years. To do the full 11 years, it would have to be manual, but you can see what NAO state is favor 1-2 years before a Solar Max/Min event at least (weaker overall correlation)

 You lost me with the bolded.

[Stormchaserchuck1]

7 minutes ago, GaWx said:

 You lost me with the bolded.

You can do "lags" and "leads"

A lead is the index comes first.. +1-24 months

A lag is the 500mb composite comes before the index.. -1-24 months

So -24 months is 2 years before a Solar Max

There is actually a -NAO signal at -24 months

-12 months before.. transitioning to Neutral

So since Solar cycles are almost perfectly cyclical, there is actually a +correlation all the way until 1 year before the next Solar peak (Min or Max)! 

So if the average cycle is 11 years, that's a 0 to +9 year NAO correlation composite

[GaWx]

2 hours ago, Stormchaserchuck1 said:

You can do "lags" and "leads"

A lead is the index comes first.. +1-24 months

A lag is the 500mb composite comes before the index.. -1-24 months

So -24 months is 2 years before a Solar Max

There is actually a -NAO signal at -24 months

-12 months before.. transitioning to Neutral

So since Solar cycles are almost perfectly cyclical, there is actually a +correlation all the way until 1 year before the next Solar peak (Min or Max)! 

So if the average cycle is 11 years, that's a 0 to +9 year NAO correlation composite

Chuck,

 If you’d look real closely at the cycles, you’d actually see that the average length from min to max is significantly shorter than that for max to min:

Cycle: Min to Max (years)/Max to Min (years)

1: 6/5

2: 3/6

3: 3/6

4: 3/11

5: 6/6

6: 6/7

7: 7/3

8: 4/6

9: 5/8

10: 4/7

11: 3/8

12: 5/6

13: 4/8

14: 4/8

15: 4/6

16: 5/5

17: 4/7

18: 3/7

19: 3/7

20: 4/8

21: 3/7

22: 3/7

23: 4/8

24: 6/5

(25: likely 5/?)

Avg of 1-24: 4.3/6.8

% of cycles with shorter rise than fall: 79%
% with opposite only 13%

——————

Aside:

-% with 11 year cycle only 25% though 11 is the average; 29% had 10 year (the mode)

-Range 9-14

-Next min very likely within 2030-32.

 

https://www.sidc.be/SILSO/DATA/SN_y_tot_V2.0.txt

[Stormchaserchuck1]

Very interesting. I think we need to separate the top half and bottom half for "max" and "min". Within that, we assign a +0-9 year lead for best predicted NAO state. For example: If year 2000-2009 is Solar Min with 2004 Solar Min peak (not really data, I am just making an example), we are saying +0-9 years makes 2004-2013 the highest probability for -NAO. I think 2024 was the peak for this Solar Max (correct me if I'm wrong), so we're saying the tendency is for 2024-2033 to be highest likelihood for +NAO, since the next 4-5 years will be declining, but still in the top half, most likely. It is only 1 year before the next Solar Cycle peaks (so coming Solar Min peak) before the NAO tendency actually changes from previous Solar Max peak!

Edit: I see 11 years is for the whole cycle to circulate, not to go from one to the other.. so it's just a +NAO tendency until 1 year before coming Solar Min peak, which your research is saying 6-7 years after Solar Max peak, so 2030-2031.. +NAO tendency until ~2029-2030

[bluewave]

19 hours ago, LibertyBell said:

What's your thinking on the NAO for next winter? Do you agree if we see more blockiness this summer and a -NAO rainy summer that the chances are higher that we will have a +NAO for the winter with less snowfall (under 20 inches for NYC)?

This is something I've noticed as a regular pattern for many decades.

The NAO and AO have become really volatile over the years. With big swings from positive to negative over very short periods. So trying to do a detailed long range AO and and NAO forecast for next winter would probably be low skill at this point. 

This past winter the AO was negative and the NAO positive. This decoupling between the 2 indices has become more common during the 2020s. Plus on the days with .25 and more of precipitation around NYC this last winter the -AO and -NAO linked up with the Southeast Ridge. 

My guess is that this is related to surface pressures rising near the Azores  during the winter. When the -AO links up with the Southeast Ridge the AO still registers as negative. But when the blocking near Iceland and Greenland links up with the East Atlantic or European Subtropical Ridge, the NAO registers as positive. So the rising pressures to the south near Europe have been preventing more -NAO winters in recent years. 

If we had lower pressures near the Azores this past winter, then it would have been a -NAO winter since pressures were above average near Iceland. Notice how much different it was from the pattern in 2010 with the record -NAO. 
 

The shift to a much more positive EA over time seems to have been also influencing the NAO.
 

https://www.cpc.ncep.noaa.gov/data/teledoc/ea.shtml

[Stormchaserchuck1]

Good post bluewave. Europe has had a really linear Winter warming trend that has spanned the last few decades. I remember seeing a graph of Germany's snowfall and it was a consistent 25 degree angle down since the 1960s/70s. Last Winter Europe was really warm, so the trend continues there.  It seems to be at least somewhat correlated to the NAO index, like you say. 

[LibertyBell]

1 hour ago, bluewave said:

The NAO and AO have become really volatile over the years. With big swings from positive to negative over very short periods. So trying to do a detailed long range AO and and NAO forecast for next winter would probably be low skill at this point. 

This past winter the AO was negative and the NAO positive. This decoupling between the 2 indices has become more common during the 2020s. Plus on the days with .25 and more of precipitation around NYC this last winter the -AO and -NAO linked up with the Southeast Ridge. 

My guess is that this is related to surface pressures rising near the Azores  during the winter. When the -AO links up with the Southeast Ridge the AO still registers as negative. But when the blocking near Iceland and Greenland links up with the East Atlantic or European Subtropical Ridge, the NAO registers as positive. So the rising pressures to the south near Europe have been preventing more -NAO winters in recent years. 

If we had lower pressures near the Azores this past winter, then it would have been a -NAO winter since pressures were above average near Iceland. Notice how much different it was from the pattern in 2010 with the record -NAO. 
 

The shift to a much more positive EA over time seems to have been also influencing the NAO.
 

https://www.cpc.ncep.noaa.gov/data/teledoc/ea.shtml

Some good reasoning right here, Chris.... what are your thoughts on the increased NAO blocking in springtime, even late springtime (May).... is this a seesaw effect to balance out what we're seeing in the winter?

[40/70 Benchmark]

On 5/9/2025 at 10:14 PM, Stormchaserchuck1 said:

Good post.. lots of data shows +years after a solar peak has the highest cold season NAO correlation

Solar Max +0 years

Solar Max +1 year

Solar Max +2 years

As you can see, the south part of the NAO measurement (central North Atlantic High pressure) increases pretty substantially +2 years time from Solar peak. The final image looks more uniform +NAO, vs just a northern latitude feature in the first image. 

Yea, I think once we get beyond 2026, it becomes less hostile for -NAO, but +NAO still favored until we hit the min early next decade. The ascending portion of the cycle is best for -NAO.

[40/70 Benchmark]

20 hours ago, Stormchaserchuck1 said:

To bluewave's point, here is the following Winter +1 year after a +PNA December

December +12 months

January +13 months

February +14 months

Somewhat of a signal there for warmer than average temps in the eastern 1/2. I didn't sort it out by negative ENSO, but the general gives you a lot more data points. It's on ok signal (ENSO usually changes state the year after a relative PNA Winter, which I will say again is interesting. It's counter-intuitive)

 

I interpret that as only really having much utility at all for February, which isn't much of a news flash that February will have shitty climo if we repeat cool ENSO. I guess I don't interpret this as being as telling as you and Chris do. But like I said, with you lock-step on the NAO.

That said, I won't be shocked if next season is RNA....so not necessarily arguing against that. I do think we are in for more PNA moving forward, though....regardless of what happens next year.

[Stormchaserchuck1]

5 hours ago, 40/70 Benchmark said:

I interpret that as only really having much utility at all for February, which isn't much of a news flash that February will have shitty climo if we repeat cool ENSO. I guess I don't interpret this as being as telling as you and Chris do. But like I said, with you lock-step on the NAO.

That said, I won't be shocked if next season is RNA....so not necessarily arguing against that. I do think we are in for more PNA moving forward, though....regardless of what happens next year.

I'm not saying that it has a lot of value.. the DJF composite probably maxes out at +0.1, which is a 55% chance of something happening. I do think that a "rogue PNA", one that is not accompanied by ENSO or ENSO changes does have a higher likelihood to even out.. But we are not seeing the same consistent Aleutian High pattern so far as 2020-2024, so we'll see.. 

[snowman19]

I interpret that as only really having much utility at all for February, which isn't much of a news flash that February will have shitty climo if we repeat cool ENSO. I guess I don't interpret this as being as telling as you and Chris do. But like I said, with you lock-step on the NAO.
That said, I won't be shocked if next season is RNA....so not necessarily arguing against that. I do think we are in for more PNA moving forward, though....regardless of what happens next year.

Obviously way too early to even begin thinking about next winter. That said, I think the only things that are obvious at this very early juncture unless something changes dramatically and unexpectedly are: 1) “cold” ENSO is a VERY good bet (question being is it going to be cold-neutral or do we see another weak La Niña?), 2) Still elevated solar and geomag 3) -QBO 4) Hedging towards another -PDO; although not severely negative like the last several 5) possible strong -IOD? 6) Likely -PMM. That’s about it for now….

[GaWx]

22 minutes ago, snowman19 said:

Obviously way too early to even begin thinking about next winter. That said, I think the only things that are obvious at this very early juncture unless something changes dramatically and unexpectedly are: 1) “cold” ENSO is a VERY good bet (question being is it going to be cold-neutral or do we see another weak La Niña?), 2) Still elevated solar and geomag 3) -QBO 4) Hedging towards another -PDO; although not severely negative like the last several 5) possible strong -IOD? 6) Likely -PMM. That’s about it for now….

Thanks. Sounds like a good and reasonable summary, snowman. The only things I’d like to add are:

-Sunspot #s for this winter will likely be lower than the prior winter’s even though still elevated

-Per RONI there could easily be another moderate peaking La Nina

[mitchnick]

1 hour ago, GaWx said:

Thanks. Sounds like a good and reasonable summary, snowman. The only things I’d like to add are:

-Sunspot #s for this winter will likely be lower than the prior winter’s even though still elevated

-Per RONI there could easily be another moderate peaking La Nina

Though too early for any real certainty, somewhere between a weak Niña to weak Niño are the table at this point, with a La Nada of some sort favored imho. SOI has been dropping lately, fwiw, per attached. When you look at everything, there really are mixed signals on how winter goes in the east imho. But, admittedly, that ain't saying much other than equivoval, meteorological drivel. But I tried my best to sound good lol.

[Stormchaserchuck1]

Nice progression of the warm pool on the CPC's subsurface

[snowman19]

Though too early for any real certainty, somewhere between a weak Niña to weak Niño are the table at this point, with a La Nada of some sort favored imho. SOI has been dropping lately, fwiw, per attached. When you look at everything, there really are mixed signals on how winter goes in the east imho. But, admittedly, that ain't saying much other than equivoval, meteorological drivel. But I tried my best to sound good lol.

Although nothing in weather is “impossible”, I would say an El Nino, even a weak one is extremely unlikely

[40/70 Benchmark]

18 hours ago, snowman19 said:

Obviously way too early to even begin thinking about next winter. That said, I think the only things that are obvious at this very early juncture unless something changes dramatically and unexpectedly are: 1) “cold” ENSO is a VERY good bet (question being is it going to be cold-neutral or do we see another weak La Niña?), 2) Still elevated solar and geomag 3) -QBO 4) Hedging towards another -PDO; although not severely negative like the last several 5) possible strong -IOD? 6) Likely -PMM. That’s about it for now….

Yea, that is resonable, although I have not closed the door on a weak  warm ENSO episode...albeit looking less likely than it was a couple months ago.

[40/70 Benchmark]

18 hours ago, GaWx said:

Thanks. Sounds like a good and reasonable summary, snowman. The only things I’d like to add are:

-Sunspot #s for this winter will likely be lower than the prior winter’s even though still elevated

-Per RONI there could easily be another moderate peaking La Nina

Descending is worse than solar max for the NAO, so that isn't going to help....not saying that you were implying it would....just as an addendum.

[Yanksfan]

I know it’s way early in the game for a legit call on next winter, but thus far I’m not liking all this negativity. I’m not looking for a blockbuster season; just give me a normal winter at this point.

[LibertyBell]

22 minutes ago, 40/70 Benchmark said:

Descending is worse than solar max for the NAO, so that isn't going to help....not saying that you were implying it would....just as an addendum.

any idea why it's worse Ray?

[40/70 Benchmark]

24 minutes ago, LibertyBell said:

any idea why it's worse Ray?

Traditionally, research correlated high levels of solar activity near solar max, as was the case for winter 2024-2025, to a stronger polar vortex and thus milder winters for much of North America and Europe. There are a multitude of theories as to why this is the case, however, most of these theories cite drivers such as UV radiation and total solar radiation (TSI), which closely mirror sunspot activity, as responsible for increasing ozone levels and temperature in the equatorial stratosphere. This warmer tropical stratosphere then results in a stronger latitudinal gradient and a cooler polar stratosphere (stronger polar vortex) via a modulated Brewer-Dobson cycle. The issue with these theories is that the peak levels of the aforementioned potential drivers of the solar-stratosphere connection coincide with solar max. And most recent research cites stronger drivers that do not coincide with solar max, such as geomagnetic energy and solar winds, which peak during solar flux or, about one year after solar max in terms of peak UV and TSI . (Maliniemi et al, 2014). Malimiemi et al theorize that geomagnetic energy makes its way into the polar region via the process of energetic particle precipitation, which then produces nitrogen oxides in the the upper atmosphere that have a protracted period of time to descend downward and increase ozone during the polar winter in the absence of any sunlight, which cools the stratosphere and strengthens the PV. This more closely corroborates both with other recent research, which cites drivers that do not peak at solar max as defined by UV and TSI (geomagnetic energy peaks approximately one year after solar max), as well as the research of Malimiemi et al (2014), which found that the declining phase of the sunspot cycle remarkably consistently produces the spacial pattern of surface temperature anomalies related to the positive NAO during the last 13 solar cycles" (Maliniemi et al, 2014). This makes sense since the geomagnetic energy peak that Maliniemi et al cite as the main driver behind the connection between the solar cycle and polar domain lags solar max as defined by UV, TSI and sunspots by approximately one year, which is during the declining phase that so strongly correlates with the +NAO response in their research.

[40/70 Benchmark]

 

 

 This implies that winter 2025-2026 and 2026-2027 will be more favorable for a stronger polar vortex than last winter, which is also consistent with other recent studies of seal level pressure patterns that revealed a +NAO pattern lagging solar max by approximately 2-4 years. 

[snowman19]

Descending is worse than solar max for the NAO, so that isn't going to help....not saying that you were implying it would....just as an addendum.

Yea, I saw your studies on it. I believe HM also touched on it in a post here many years ago….descending solar after a max is actually worse for NAO and AO blocking than it is at peak solar max

[40/70 Benchmark]

5 minutes ago, snowman19 said:

Yea, I saw your studies on it. I believe HM also touched on it in a post here many years ago….descending solar after a max is actually worse for NAO and AO blocking than it is at peak solar max

It was also evident in Chuck's correlation maps, too....+NAO signal peaked 2 years post max...so I think we are porked with respect to the polar domain for the next couple of winters. Its not a death knell, as there are ways around that, but it certainly makes the path to a good winter more elusive.

[40/70 Benchmark]

On 5/9/2025 at 10:14 PM, Stormchaserchuck1 said:

Good post.. lots of data shows +years after a solar peak has the highest cold season NAO correlation

Solar Max +0 years

Solar Max +1 year

Solar Max +2 years

As you can see, the south part of the NAO measurement (central North Atlantic High pressure) increases pretty substantially +2 years time from Solar peak. The final image looks more uniform +NAO, vs just a northern latitude feature in the first image. 

 

[LibertyBell]

1 hour ago, Yanksfan said:

I know it’s way early in the game for a legit call on next winter, but thus far I’m not liking all this negativity. I’m not looking for a blockbuster season; just give me a normal winter at this point.

I have a fairly easy rule of thumb I use that seems to work well.  If the summer is hot and dry it will be a snowy cold winter.  If summer is rainy and not so hot, then the winter will have very little snowfall or cold.

 

[40/70 Benchmark]

14 minutes ago, LibertyBell said:

I have a fairly easy rule of thumb I use that seems to work well.  If the summer is hot and dry it will be a snowy cold winter.  If summer is rainy and not so hot, then the winter will have very little snowfall or cold.

 

We must be turning into a tropical rain forest this decade.