2025-2026 ENSO

[mitchnick]

Negative PDO may have peaked with notable cooling around Japan over the past 15 days.

[donsutherland1]

With some of the guidance hinting at the development of a 600 dm heat dome in the vicinity of the Rockies, there is already a strong heat signal showing up east of the Rockies. That area of heat will likely shift westward the following week. As the heat shifts westward, places like Denver could approach or reach 100° on one or more days. Parts of Kansas and Oklahoma could see numerous days with highs of 100° or above. Phoenix could see another stretch of 110°+ heat with a possible 115° high. The Northeast, especially New England, could turn cooler than normal for a time.

 

[40/70 Benchmark]

16 minutes ago, mitchnick said:

Negative PDO may have peaked with notable cooling around Japan over the past 15 days.

I think I recall this happening last season....the PDO bottomed out last fall as if Armageddon loomed for winter enthusiasts, and then steadily reversed throughout last winter. Obviously it will remain at least somewhat negative throughout winter, though...as it did last season.

[40/70 Benchmark]

Anyone have any idea when they are going to update the MEI?

[mitchnick]

18 minutes ago, donsutherland1 said:

With some of the guidance hinting at the development of a 600 dm heat dome in the vicinity of the Rockies, there is already a strong heat signal showing up east of the Rockies. That area of heat will likely shift westward the following week. As the heat shifts westward, places like Denver could approach or reach 100° on one or more days. Parts of Kansas and Oklahoma could see numerous days with highs of 100° or above. Phoenix could see another stretch of 110°+ heat with a possible 115° high. The Northeast, especially New England, could turn cooler than normal for a time.

 

Transient as it breaks the following week.

[donsutherland1]

1 minute ago, mitchnick said:

Transient as it breaks the following week.

Yes, it's shifting westward. The heat will probably be more prolonged in the western half of the CONUS than the eastern half. 

[bluewave]

35 minutes ago, 40/70 Benchmark said:

I think I recall this happening last season....the PDO bottomed out last fall as if Armageddon loomed for winter enthusiasts, and then steadily reversed throughout last winter. Obviously it will remain at least somewhat negative throughout winter, though...as it did last season.

I like to use the PDO as a marker or gauge of what the 500mb pattern is doing. Since it’s being driven during the 2020s by these extreme 500 mb ridges across the Pacific leading to similar ridging across the U.S. across the Atlantic. So the strong -PDO is  more indicative of the record warm SSTs than the cold ones in the old days. 

Sometimes during the cold season we see an October -PDO peak like in 2024 and 2021. Then a rebound heading into both winters.  But it’s a signal that a very strong subtropical 500mb ridge may occur in the following months. While we had the strong -PDO mismatch last December, there was a very strong subtropical ridge from near Hawaii right into the Western Gulf. So last December was the 4th warmest on record for the CONUS.

Back in 2021 we had the October -PDO peak which rose off those lows into December. But it was a signal that the 500 mb ridge driving the -PDO was very robust. This is when we had the record breaking Aleutian Ridge that December leading to the 2nd warmest December on record for the CONUS.

 

[40/70 Benchmark]

How did I know that Bluewave's advanced optimism alarm system detected a faint modicum of hope in my post, and that he would rush to the scene to douse the flame in short order. Dude is the Darthvader of seasonal forecasting.

[40/70 Benchmark]

24 minutes ago, bluewave said:

All these discussions and maps for me don’t have anything to do with emotions. It’s just simply a pattern analysis and discussion of what the recent pattern progressions have been.

The real Darthvader you are referencing is the actual pattern which have been developing especially over the last decade. Once you start letting emotions creep into the process it taints your ability to make an objective analysis.

Most on here would rather keep expectations realistic and then get surprised to the upside at least in a small way rather than expecting some big shift from these 2020s winters only to be disappointed again. 

 

It was merely making an anecdotal observation pertaining to the behavior of the PDO; nothing more. I wasn't deducing anything from it. Do I think the PDO will rise this winter? Yes...do I think that will be particulary important? No. I have already said that the PNA is likely to be more consistently negatibve than last season and that I expect the +WPO to continue. I forecast seasonal index behavior, not just weather....so the behavior of the PDO independent of the actual weather is relevent.

There wasn't any emotion involved...I was simply adding a little levity to the discussion, as I so often do. But it is true that I can always discern which posts you will swarm to like an ant to spilled soda...I knew how my post would be perceived ostensibly speaking, which would prompt a replay form you.

[snowman19]

Looks much more temporary when you look at the graphs at the top and bottom of this page.
https://solen.info/solar/index.html

As Ray has mentioned a few times, descending solar from a solar max peak is actually more hostile to NAO/AO blocking in winter than it is right at solar max peak

[GaWx]

1 hour ago, mitchnick said:

Negative PDO may have peaked with notable cooling around Japan over the past 15 days.

 Indeed, it’s not surprisingly bounced 0.50 from the extreme low of -3.45 of 7/8/25. This -2.95 WCS PDO translates to ~-3.75 NOAA PDO. NOAA’s dip on 7/8/25 was likely sub -4!

[40/70 Benchmark]

9 minutes ago, snowman19 said:

As Ray has mentioned a few times, descending solar from a solar max peak is actually more hostile to NAO/AO blocking in winter than it is right at solar max peak

Looks like August 2024 was the peak?

It takes a couple of years for the solar wind to in increase enough to kick up the geomagnetic particles, which is what is the most hostile for blocking....we may sneak by with one more season that is not awful.

"recent studies of seal level pressure patterns that revealed a +NAO pattern lagging solar max by approximately 2-4 years. The work of Maliniemi et al also showed that this relationship is not at all dependent on overall sunspot activity due to intra-cycle variability."

 

Mean winter NAO index values for the four cycle phases, averaged over cycles 11 to 23. The red line represents the overall mean value of wintertime NAO (0.05). Bars represent the 95% confidence interval

[40/70 Benchmark]

The season should def. average +NAO...I am just speaking to how favorable or unfavorable it is to steal a -NAO month or two.

[bluewave]

1 hour ago, 40/70 Benchmark said:

It was merely making an anecdotal observation pertaining to the behavior of the PDO; nothing more. I wasn't deducing anything from it. Do I think the PDO will rise this winter? Yes...do I think that will be particulary important? No. I have already said that the PNA is likely to be more consistently negatibve than last season and that I expect the +WPO to continue. I forecast seasonal index behavior, not just weather....so the behavior of the PDO independent of the actual weather is relevent.

There wasn't any emotion involved...I was simply adding a little levity to the discussion, as I so often do. But it is true that I can always discern which posts you will swarm to like an ant to spilled soda...I knew how my post would be perceived ostensibly speaking, which would prompt a replay form you.

Yes. I get the humor involved.  Not trying to rain on anyone’s parade. Just taking note of the pattern and where it has gone in the recent past with these persistent base states across the mid-latitudes. 

[so_whats_happening]

4 hours ago, snowman19 said:

I’m talking wide spread CONUS summer humidity/heat this extreme

I get what you are saying but locking it regionally (Midwest/ Ohio Valley) like you posted is not factual. It has been a warm summer I would actually say last summer was probably warmer than this year has been for the CONUS but we won't know until late August. 

Humidity/ dew point wise nothing really has been that different from prior years across the CONUS we are still hitting our low to even mid 70s consistently around here in the mid atlantic like we have over numerous years. The corn crop is still causing  evapotranspiration as it has, hopefully this dies off as we move into a less HFCS type of lifestyle. 

[so_whats_happening]

2 hours ago, donsutherland1 said:

With some of the guidance hinting at the development of a 600 dm heat dome in the vicinity of the Rockies, there is already a strong heat signal showing up east of the Rockies. That area of heat will likely shift westward the following week. As the heat shifts westward, places like Denver could approach or reach 100° on one or more days. Parts of Kansas and Oklahoma could see numerous days with highs of 100° or above. Phoenix could see another stretch of 110°+ heat with a possible 115° high. The Northeast, especially New England, could turn cooler than normal for a time.

 

Hopefully we can get some heat dome MCS events before it shifts.

[so_whats_happening]

2 hours ago, 40/70 Benchmark said:

I think I recall this happening last season....the PDO bottomed out last fall as if Armageddon loomed for winter enthusiasts, and then steadily reversed throughout last winter. Obviously it will remain at least somewhat negative throughout winter, though...as it did last season.

Yes it something very similar to this last year I believe we may have peaked a bit earlier this year than we did last year but will see how the 500mb sets up over the next few weeks to give clues. Some models want to slowly erode the 500mb high setup versus others just obliterating it (frickin GFS). 

1 hour ago, GaWx said:

 Indeed, it’s not surprisingly bounced 0.50 from the extreme low of -3.45 of 7/8/25. This -2.95 WCS PDO translates to ~-3.75 NOAA PDO. NOAA’s dip on 7/8/25 was likely sub -4!

We should take a run at the lowest monthly value but probably fall short depending on how quickly things level out.

12 minutes ago, bluewave said:

Yes. I get the humor involved.  Not trying to rain on anyone’s parade. Just taking note of the pattern and where it has gone in the recent past with these persistent base states across the mid-latitudes. 

It has been raining quite a bit of late for that lol

[40/70 Benchmark]

Not that its a big deal considering La Nina shouldn't be too strong, but JMA seems to imply an east based event along the lines of 2021. Just speaking of La Nina  EMI...I do realize that solar is much different and La Nina will be weaker.

JMA hovers the EMI around -.3 or so during the winter...which is similar to 1995-1996, 2017-2018 and 2021-2022. First of all...no, 1995-1996 is not a seasonal analog, so please spare me Bluewave's wrath (jk....kinda). But signs like this reenforce my early suspicion that this will not be a wall-to-wall death star season.

[40/70 Benchmark]

I think we are going to see some variation and another periood of the season that deviates from the west Pac urine pool.

[so_whats_happening]

Shoot the messenger or don't (please don't) but there are definitely some similarities SST wise to 2013 and 2017 to this year so far. Yes I know 2013 is not happening same ol same ol but one can still analyze the aspects of how similar they are still somehow. You could even try to throw in 2021 if the Nina can actually try to be something SST wise.

This year we have just overall bumped the warmer mid latitudes compared to those years.

[40/70 Benchmark]

6 minutes ago, 40/70 Benchmark said:

Not that its a big deal considering La Nina shouldn't be too strong, but JMA seems to imply an east based event along the lines of 2021. Just speaking of La Nina  EMI...I do realize that solar is much different and La Nina will be weaker.

JMA hovers the EMI around -.3 or so during the winter...which is similar to 1995-1996, 2017-2018 and 2021-2022. First of all...no, 1995-1996 is not a seasonal analog, so please spare me Bluewave's wrath (jk....kinda). But signs like this reenforce my early suspicion that this will not be a wall-to-wall death star season.

 

Just now, so_whats_happening said:

Shoot the messenger or don't (please don't) but there are definitely some similarities SST wise to 2013 and 2017 to this year so far. Yes I know 2013 is not happening same ol same ol but one can still analyze the aspects of how similar they are still somehow. You could even try to throw in 2021 if the Nina can actually try to be something SST wise.

This year we have just overall bumped the warmer mid latitudes compared to those years.

Jinx.

 

I will add that JMA essentially ENSO neutral, too....slight hedge towards cool ENSO, so the EMI really isn't a big deal, but I would rather have it east all things equal. Yes, snowman...I know how the Pacific looks right now...just speaking of the model.

[40/70 Benchmark]

@ORH_wxmanWas actually metioning the other day how this year kind of resembles some of the older cool ENSO events in that there is more cooler water near the west coast than in the recent ones.

[so_whats_happening]

1 minute ago, 40/70 Benchmark said:

 

Jinx.

 

I will add that JMA essentially ENSO neutral, too....slight hedge towards cool ENSO, so the EMI really isn't a big deal, but I would rather have it east all things equal. Yes, snowman...I know how the Pacific looks right now...just speaking of the model.

Lol I just saw that. Given early indications of simply just looking at configurations I don't think this is a bad take for potentially happening this winter.

[GaWx]

16 minutes ago, so_whats_happening said:

We should take a run at the lowest monthly value but probably fall short depending on how quickly things level out.

  Agreed. But if it turns back down by the end of this month, the record NOAA PDO low of October 2024’s -3.80 would be in danger. For MTD, it’s likely in that vicinity now. That table goes way back to 1854.

[40/70 Benchmark]

Just now, so_whats_happening said:

Lol I just saw that. Given early indications of simply just looking at configurations I don't think this is a bad take for potentially happening this winter.

Yea, I think we will have some servicable stretches...but overall the west-urine pool does of course remain.

[40/70 Benchmark]

I don't want to sound too optimistic because Bluewave will be on my door step.

[so_whats_happening]

Just now, GaWx said:

  Agreed. But if it turns back down the record NOAA PDO low of October 2024’s -3.80 would be in danger. For MTD, it’s likely in that vicinity now.

If we get any potential of Typhoon action and especially recurving Typhoon action it will fail. 

[40/70 Benchmark]

@bluewaveSeriously, though....I do recall telling you last season that I expected your October MJO indicator to be amplified and favorable and I do expect that again, so we'll see.

[bluewave]

5 minutes ago, 40/70 Benchmark said:

@ORH_wxmanWas actually metioning the other day how this year kind of resembles some of the older cool ENSO event in that there is more cooler water near the west coast than in the recent ones.

Narrowly focused into the Bay Area in an otherwise sea of warm across the Northern Hemisphere this summer.

 

[so_whats_happening]

11 minutes ago, 40/70 Benchmark said:

Yea, I think we will have some servicable stretches...but overall the west-urine pool does of course remain.

Yea it is reasonable to think we break the mode every once in awhile like we did last year. I have been meaning to see what inevitably breaks the -PDO down from past events regardless of value. What trigger atmospherically kicks it down and switches it over because as we have seen ENSO doesn't quite do the trick.

Im more so excited for the break from the 70+ dew points coming up on tuesday.