2025-2026 ENSO

[Stormchaserchuck1]

^I would say there was more +PNA, low pressure over the north Pacific in those two analogs. Feb 2014 looks like a pretty good N. Hemisphere 500mb match though. It takes about 6 days for a Pacific-PNA change to work its way to the SE ridge. We had a strong Aleutian High late Jan-early Feb.  The south-based +NAO kept the SE ridge amped after that, without a major North Pacific trough present to cut it down.  AO 50 degrees further north is not a big deal when there are strong anomalies closer, and the Pacific had a large part to do with the colder patterns in those 2 analogs. 

[Stormchaserchuck1]

Importance of the +PNA for coastal low tracks bluewave

Low's hug the coast in that pattern. CPC says it was +PNA, but the 500mb maps don't show that. We didn't have that piece in February. We had that piece in Feb 2016, and somewhat Feb 2014 (but it was much more -WPO in Feb 2014). 

WPO air temp correlation in Feb (opposite) - +200dm anomaly overpowered and kept Feb 2014 cold. 

+NAO was also further east - -200dm over England in Feb 2014. This one was closer to us. 

 

[Stormchaserchuck1]

AAO correlation worked out last year - It was a very negative Aug/Sept AAO, and that rolled forward to a pretty strong signal on a cold December/January, -AO, North Pole was +0.5 correlation rolled forward. 

AAO has been very positive March - May, all but like 5 days positive. 

How that rolls forward to the following N. Hemisphere Winter

+9 months is a lot of time, but it's an ok signal. This is what I would think +AAO would look like down the line (slight correlation with AO/EPO)

[bluewave]

13 hours ago, Stormchaserchuck1 said:

^I would say there was more +PNA, low pressure over the north Pacific in those two analogs. Feb 2014 looks like a pretty good N. Hemisphere 500mb match though. It takes about 6 days for a Pacific-PNA change to work its way to the SE ridge. We had a strong Aleutian High late Jan-early Feb.  The south-based +NAO kept the SE ridge amped after that, without a major North Pacific trough present to cut it down.  AO 50 degrees further north is not a big deal when there are strong anomalies closer, and the Pacific had a large part to do with the colder patterns in those 2 analogs. 

I agree with you that the 500 mb pattern in February was actually -PNA. But it was also -PNA in February 2014 with lower heights in the PNA region when we had around 30” inches of snow that month in NYC. The main difference was that the Southeast Ridge and Pacific Jet weren’t factors back in 2014 like they have become today. That big jet extension east of Japan coupled with a Southeast Ridge keeps the storm tracks through the Great Lakes.

 

 

 

 

[40/70 Benchmark]

14 hours ago, bluewave said:

We can’t blame the WPO for last winter since there was a decent -WPO interval during the Feb 1 to Feb 21 with a solid block in the Bering Sea.This also coincided with a -5 daily -AO which reliably produced KU snowstorms in the past. Very difficult to pull off with such a powerful Northern Stream of the Pacific Jet which gave us a potent Great Lakes cutter at the some time the -AO was down near -5. So another Southeast Ridge link up with Greenland to Iceland blocking. 
 

https://www.ncei.noaa.gov/access/monitoring/monthly-report/synoptic/202502

 

 

 

 

 

First of all, in the mean the WPO was very positive last season...that can't be dismissed. Secondly, the NAO was very positive througout February....thirdly, even during any brief instances during which the WPO and NAO were favorable, the PNA ridge was OFF of the west coast. Sorry, that wouldn't work in 1925, either.

2013-2014 had a vastly different Western Pacific...very +WPO. Now, that maybe linked to the strong Pac jet, so maybe we aren't in as stark disagreement as it may appear.

PS: Thanks for the link!

[40/70 Benchmark]

The reality is that more often than not, there is a flaw in the pattern that will prevent a major snowstorm on the east coast...that is why averages are not higher. Its not always attributable to CC, but obviously that is becoming more of a factor. There are also times when nothing is ostensibly "wrong" with the pattern and it turns out that an act of god simply wasn't on the calendar....that can happen, too....this is why snowfall is subject to such a large degree of variance and is so difficult to predict. Mother nature is not bound by any of our rules...if she doesn't want to play ball, then she simply won't-

Sometimes the reason why is apparent, other times not so much.

[40/70 Benchmark]

Man, @bluewave that link is an absolute pants tent.....you always casually pull these elite data sources out of your rear...too bad you never use your power for good, instead of in support of trying to convince us all that the Pacfic Jet is about to eat us.

[bluewave]

12 minutes ago, 40/70 Benchmark said:

Man, @bluewave that link is an absolute pants sent.....you always casually pull data sources out of your rear...too bad you never use your power for good, instead of in support of trying to convince us all that the Pacfic Jet is about to eat us.

Nothing is about to eat us…LOL. Most people off these forums like milder and less snowy winters. This is why most people are moving to the sunbelt instead of to the cooler and snowier spots like Marquette and Caribou. 

I point out the changes in the Pacific Jet for the very reason that I enjoy colder and snowier weather. So in order to understand how we could potentially change up this pattern is key for winter weather fans. We have to change the Pacific side and Southeast Ridge trends in order to bring back some great winter weather here. 

I grew up in the 70s and had to wait at the bus stop during those little ice age throwback winters. Also fond memories of the Great 1980s into early 1990s Arctic outbreaks. So I am more a fan of cooler climates than ones that have become much warmer. 

I have been trying to think how we could change up the Pacific in order to bring back more of a STJ influence. Would probably involve a very potent El Niño that would be very warm. But I am fine with winter warmth provided there are great snowstorms like in 15-16, 16-17, 17-18, and 20-21.

 

 

[40/70 Benchmark]

4 minutes ago, bluewave said:

Nothing is about to eat us…LOL. Most people off these forums like milder and less snowy winters. This is why most people are moving to the sunbelt instead of to the cooler and snowier spots like Marquette and Caribou. 

I point out the changes in the Pacific Jet for the very reason that I enjoy colder and snowier weather. So in order to understand how we could potentially change up this pattern is key for winter weather fans. We have to change the Pacific side and Southeast Ridge trends in order to bring back some great winter weather here. 

I grew up in the 70s and had to wait at the bus stop during those little ice age throwback winters. Also fond memories of the Great 1980s into early 1990s Arctic outbreaks. So I am more a fan of cooler climates than ones that have become much warmer. 

I have been trying to think how we could change up the Pacific in order to bring back more of a STJ influence. Would probably involve a very potent El Niño that would be very warm. But I am fine with winter warmth provided there are great snowstorms like in 15-16, 16-17, 17-18, and 20-21.

 

 

We need to cool off the west Pac....or at least relative to the east Pac...the ratio right now (warmer west/cool east) predisposes us to a cool ENSO paradigm...that is why we have been having problems on the east coast due to se ridges and strong jets obliterating PNA ridges. That is cool ENSO like. I think we actually agree on alot, but just emphasize different aspects and drivers.

[40/70 Benchmark]

I think given (potentially) ENSO neutral this coming season, you have weight things towards modest cool ENSO.

[bluewave]

6 minutes ago, 40/70 Benchmark said:

We need to cool off the west Pac....or at least relative to the east Pac...the ratio right now (warmer west/cool east) predisposes us to a cool ENSO paradigm...that is why we have been having problems on the east coast due to se ridges and strong jets obliterating PNA ridges. That is cool ENSO like. I think we actually agree on alot, but just emphasize different aspects and drivers.

You have to wonder how much the EPAC needs to warm in order to offset the warming in the WPAC. While 2023-2024 was the warmest winter on record across the CONUS, at least we had that great record breaking STJ in February with the El Niño. That was a nice snowstorm in a narrow zone between NYC and Philly. Unfortunately, it didn’t extend very far from this region since it was more of a mesoscale IVT feature.

My attitude is that I would much rather roll the dice with a strong El Niño and STJ influence no matter how warm to just get the storm track further south. Heck, even in March 1998 we had a better snowstorm than we have seen in recent years even though it was also a very mild winter. This persistent Niña background since 2018-2019 has shifted the storm track too far north for many of us. 
 

Monthly Data for March 1998 for Upton NY NWS CWA
Click column heading to sort ascending, click again to sort descending.

NY	YORKTOWN HEIGHTS 1W	COOP	9.0
NJ	GREENWOOD LAKE	COOP	8.5
NY	WEST POINT	COOP	8.0
NY	WALDEN 1 ESE	COOP	6.5
NY	PORT JERVIS	COOP	6.1
NJ	CHARLOTTEBURG RESERVOIR	COOP	6.0
NY	NY CITY CENTRAL PARK	WBAN	5.0
NJ	WANAQUE RAYMOND DAM	COOP	4.8
NJ	RINGWOOD	COOP	4.8
NY	LAGUARDIA AIRPORT	WBAN	4.7
NJ	CANOE BROOK	COOP	4.5
NJ	HARRISON	COOP	4.5
NY	WEST NYACK	COOP	4.5
NY	MINEOLA 1 NE	COOP	4.2
NJ	MIDLAND PARK	COOP	4.0
CT	DANBURY	COOP	4.0

 

[40/70 Benchmark]

1 minute ago, bluewave said:

You have to wonder how much the EPAC needs to warm in order to offset the warming in the WPAC. While 2023-2024 was the warmest winter on record across the CONUS, at least we had that great record breaking STJ in February with the El Niño. That was a nice snowstorm in a narrow zone between NYC and Philly. Unfortunately, it didn’t extend very far from this region since it was more of a mesoscale IVT feature.

My attitude is that I would much rather roll the dice with a strong El Niño and STJ influence no matter how warm to just get the storm track further south. Heck, even in March 1998 we had a better snowstorm than we have seen in recent years even though it was also a very mild winter. This persistent Niña background since 2018-2019 has shifted the storm track too far north for many of us. 
 

Monthly Data for March 1998 for Upton NY NWS CWA
Click column heading to sort ascending, click again to sort descending.

NY	YORKTOWN HEIGHTS 1W	COOP	9.0
NJ	GREENWOOD LAKE	COOP	8.5
NY	WEST POINT	COOP	8.0
NY	WALDEN 1 ESE	COOP	6.5
NY	PORT JERVIS	COOP	6.1
NJ	CHARLOTTEBURG RESERVOIR	COOP	6.0
NY	NY CITY CENTRAL PARK	WBAN	5.0
NJ	WANAQUE RAYMOND DAM	COOP	4.8
NJ	RINGWOOD	COOP	4.8
NY	LAGUARDIA AIRPORT	WBAN	4.7
NJ	CANOE BROOK	COOP	4.5
NJ	HARRISON	COOP	4.5
NY	WEST NYACK	COOP	4.5
NY	MINEOLA 1 NE	COOP	4.2
NJ	MIDLAND PARK	COOP	4.0
CT	DANBURY	COOP	4.0

 

I would still prefer a more meager El Nino....I am far enough north where I still want a good deal of N steam involvement, or it ends up occluded after a mid atl snowmaggedon.

[40/70 Benchmark]

Interesting that the Euro and Aussie have a warm neutral.....hasn't the EURO been running hot for ENSO?

[bluewave]

56 minutes ago, 40/70 Benchmark said:

I would still prefer a more meager El Nino....I am far enough north where I still want a good deal of N steam involvement, or it ends up occluded after a mid atl snowmaggedon.

Yeah, in the old days I would have agreed with you. But after we saw how the WPAC completely overpowered that weak El Niño in 2018 -2019,  I have my doubts that a weak El Niño could work with this Pacific SST configuration.

At least January 2019 was nice for the cold fans in the Midwest with the record cold near Chicago. But DJF was a real dud for snowfall around NYC with the La Niña background pattern and nearly no snowfall over those 3 months.

Plus the weak modoki El Niño signature in 2019-2020 that was overshadowed by the record IOD supercharging the SPV. But at least we got some El Niño backloading with the record May snows. Unfortunately, we needed that storm track much earlier in the spring in order to really produce. 

[40/70 Benchmark]

26 minutes ago, bluewave said:

Yeah, in the old days I would have agreed with you. But after we saw how the WPAC completely overpowered that weak El Niño in 2018 -2019,  I have my doubts that a weak El Niño could work with this Pacific SST configuration.

At least January 2019 was nice for the cold fans in the Midwest with the record cold near Chicago. But DJF was a real dud for snowfall around NYC with the La Niña background pattern and nearly no snowfall over those 3 months.

Plus the weak modoki El Niño signature in 2019-2020 that was overshadowed by the record IOD supercharging the SPV. But at least we got some El Niño backloading with the record May snows. Unfortunately, we needed that storm track much earlier in the spring in order to really produce. 

Keep in mind when I say "weak El Nino", that is a broad, general classification of the protptypical weak El Nino paradigm....once we actually get into the season, I will dig in more...obviously if we still have a Pacific cold phase/-RONI, then it probably wouldn't work. I incorporate all of that later in the fall.

Yea, 2018-2019 was a tough one...I went big that season, but the early Jan SSW (focused on other side of globe) just served to lock the residual MC forcing from prior cool ENSO into place. This was also evident by the very paltry mid season MEI. El Nino wasn't running the show.

[bluewave]

On 5/20/2025 at 2:14 PM, michsnowfreak said:

I can't wait for one of those winters where the coldest anomalies on the globe spill into the US, giving a brutal winter and TCC and company will distraughtly be posting how warm it is elsewhere on the globe. 

The closest that we got to that was February 2021. It was actually the 19th coldest for the entire CONUS and 9th coldest in the Great Plains. But since the Northern Hemisphere was pretty mild overall, the cold was only able to occupy a narrow portion of the Central CONUS. 

This is why global temperatures are so important in determining what the range of winter potential here in the CONUS. Less cold means a smaller area will have the cold coverage. This is why the cold was narrowly focused into the Plains and the East Coast was just a little colder than average. If this was the 1970s the cold would have been much more extensive.

What may seem like a few tenths to a degree or more globally has very large consequences locally to nationally. This is why we need to know the global to continental patterns in order to know the range of parameters for the winter forecast. The difference between a .250 and .330 batting average to someone that doesn’t follow baseball may seem trivial. But it’s the difference between an average hitter and a baseball leading batting average. 

Some would say that even though the winters are much warmer these days, what’s the difference since even in a warm winter I still need a coat and gloves. While the 2023-2024 winter was the warmest since 1895 in Michigan at 30.5°, it still felt cold outside. This average was still colder than every NYC winter since the 1970s. 

A colder winter climate like Michigan will always have more leeway. But where many of us live near the East Coast is along the margins as we warm. So a small shift in storm tracks on a global scale from just SE of I-95 near the Benchmark to west of the big cities and further into the Great Lakes makes a world of difference for our sensible weather. 
 

 

[Stormchaserchuck1]

We have been getting -EPO's, and even -PNA's can deliver big cold shots. There have been a few cases of good -AO's too with 500mb ridging over the Davis Strait and Greenland. Lack of clear +PNA and -NAO is why the SE ridge has persisted and storm tracks have not been benchmark. There have been I think 3 Winter months of +PNA/-NAO since 2016 (when it should happen 1/4 times). We did get +PNA/-NAO for the first 2 weeks of January in 2025, and it did give DC an 8" snowstorm. The reason it didn't hit further north was a lot because of a "Moderate Nina-like" STJ.  Because of these indexes the cold has not spread east, and has been confined to the Midwest. They have had some impressive cold shots in the Midwest though. When the global temp is +2F higher, the cold is not going to be as widespread, but the indexes have been a large part of the problem, especially wrt snowfall. +PNA/-NAO is 5x more likely to give a benchmark storm track than -PNA/+NAO. 

[PhiEaglesfan712]

2018-19 was a nearly identical winter to 2016-17. Both were C to C- winters, with a lot of nickel-and-dimers, but no real snowstorm. Both are notable for having their most notable storm outside of the DJF period (18-19 in mid-November, and 16-17 in mid-March). 18-19 did have its moments of cold (November and March were well below average, and DJF was only about +1, +2 above average), while 16-17 was a blowtorch pretty much all winter (with the exception of March).

[40/70 Benchmark]

https://easternmassweather.blogspot.com/2025/05/modest-cool-enso-influences-may-persist.html

 

[GaWx]

14 hours ago, 40/70 Benchmark said:

Interesting that the Euro and Aussie have a warm neutral.....hasn't the EURO been running hot for ENSO?

Year: May forecast for ASO BoM/Euro, actual ASO, BoM miss vs Euro miss

2024: -0.1/-0.5    -0.2  +0.1 vs -0.3

2023: +2.5/+1.8  +1.6  +0.9 vs +0.2

2022: -0.4/-0.3   -1.0   +0.6 vs +0.7

2021: -0.5/0.0      -0.7   +0.2 vs +0.7

2020: -0.8/-0.3    -0.9   +0.1 vs +0.6

2019: +0.2/+0.7   +0.2    0.0 vs +0.5

2018: -0.2/+0.6    +0.5   -0.7 vs +0.1

2017: +0.2/+0.8.   -0.4    +0.6 vs +1.2

2016: -0.8/-0.5     -0.6    -0.2 vs +0.1

2015: +1.6/+2.4    +2.2   -0.6 vs +0.2

2014: +0.8/+1.5    +0.2   +0.6 vs +1.3

2013: -0.8/-0.1      -0.3.   -0.5 vs +0.2

-----------------------------------

2012: +0.9/+0.8    +0.4   +0.5 vs +0.4

2011: +1.2/-0.2      -0.8    +2.0 vs +0.6

2010: -0.4/-0.9     -1.6     +1.2 vs +0.7

2009: +1.4/+0.8    +0.7    +0.7 vs +0.1

2008: +0.3/-0.2    -0.2     +0.5 vs 0.0

2007: -1.0/-0.8      -1.1      +0.1 vs +0.3

-----------------------------------

2006: -1.0/+0.4    +0.3     -1.3 vs +0.1

2005: +1.0/+0.4    -0.1     +1.1 vs +0.5

2004: +0.7/+0.5   +0.6    +0.1 vs -0.1

2003: -0.9/-0.4    +0.2    -1.1  vs -0.6

2002: +1.0/+0.7    +0.9    +0.1 vs -0.2

-------------------------------------

Analysis:

1) 2023-4:

-BOM had avg miss of +0.5

-Euro had ~no net bias; 2024 was 1st time May Euro was too cool since way back in 2004 (major outlier)!
 

2) 2013-22:

 - BoM had no net bias (average miss of 0.0) with 3 significantly too warm and 3 significantly too cold

- Euro had a strong warm bias (average miss of +0.6) with 6 of 10 significantly too warm

- BoM cooler than Euro 10 of 10 and significantly colder 8 of 10 years

3) 2007-12:

- BoM had a strong warm bias (average miss of +0.8) with 5 of 6 significantly too warm

- Euro had a moderate warm bias (average miss of +0.35) with 2 of 6 significantly too warm

- BoM warmer than Euro 5 of 6

 

4) 2002-06: based on JAS, not ASO

- BoM had a moderate cold bias (average miss of -0.4) with 2 of 5 significantly too cold and 1 of 5 significantly too warm

- Euro had no net bias (avg miss ~0)

——————

 

May 2025 predictions for ASO:

BoM +0.4

Euro +0.1

Conclusions

-Based just on these two, I’d lean to ~-0.2 ASO ONI. 
-But the two most accurate May forecasts overall for ASO have recently been the UKMET and JMA. UK has it way down to -0.9 and JMA has -0.5. Also, MetFrance tends to be too warm. It’s at 0.0.
-So, based on all of these 5, I’d lean to ~-0.5 for ASO ONI as of now (vs -0.2 in 2024). That implies ASO RONI of ~-1.0.

-Based on UKMET’s recent high accuracy, I won’t rule out it getting even colder than -0.5. However, the May -0.9 is a strong outlier and looks too cold to me as of now. 

 

[PhiEaglesfan712]

The fact that we're having a 2nd nor'easter since April 11 makes me more confident that the WPAC jet is changing and that a 2013-14 winter is coming in 2025-26. We have all the other pieces in place. If the WPAC jet cooperates, a cold and snowy winter is almost certain in the Eastern US.

[Imagine if the April 11-12 and this event had happened in January/February.]

[Stormchaserchuck1]

Well the PNA isn't changing. Today's daily reading is approaching the most negative daily since December 2021. 

it's looking more like those +PNA this past Winter were more a blip than a change in the long term state.. remember, 2020-2024 was the most negative PDO on record going back to the 1800s, and October 2024 had the lowest monthly PDO on record. It may take some time to change that, although I do think a more active sun could help. 

What we are getting now is a -NAO, which just hasn't been happening in the Winter, although that could of course change going forward.