2024-2025 La Nina

[snowman19]

1 hour ago, raindancewx said:

He's just using the SST matching tool from Tropical Tidbits but this is similar overall to my thoughts on the winter. Haven't written my forecast yet though. I do think the Atlantic ridging will setup somewhat west of where he shows it though.

https://www.tropicaltidbits.com/analysis/hsanalog/

I don't like 2017 as an analog - it's the most active September hurricane season since 1850, with low solar and weakly positive PDO conditions. The other years are high solar, and less active hurricane seasons with more -PDO conditions. ACE has to be 50% above normal for the rest of the season to catch up to normal. My rule is ~95%+ of seasons will finish between June-Sept and June-Sept + 60 ACE. To me it's about 50/50 that we'll hit 90 ACE.

Besides the PDO, solar/geomag and ACE not matching, 2017 was also -QBO, it was a very east-based La Niña and there was no New Foundland warm pool, the +AMO configuration was completely different. The MJO behavior back then also doesn’t match this year. Why BAMWX is saying it’s a good analog is totally beyond me

[snowman19]

14 hours ago, donsutherland1 said:

Climate change is influencing patterns, particularly from large-scale marine heatwaves. The current PDO- is one example. The increased frequency of the MJO's residing in the Marine Continent phases is another. That's why some seasonal forecasting methodologies based largely on analogs (even when the variables closely fit) now consistently perform poorly.

Winter forecasts have been in constant fail mode since the 15-16 winter because of the MJO/West PAC marine heatwave and the strong -PDO. 

‘

Real curious to see what the MEI does this month….with the 30 day SOI near +5, the increasingly negative PDO, developing -PMM, cooling/increased trades in region 3.4, falling IOD (at -0.07), Niña forcing reflected in the global OLR…a very well coupled system is in place. Let’s see if the new MEI reflects this….  ‘

[40/70 Benchmark]

12 hours ago, PhiEaglesfan712 said:

Considering the MEI is already at -0.7 (it's already achieved weak la nina status for 2024-25), I think the AS reading should be deep into moderate la nina territory, possibly even reach the strong la nina threshold.

Nah, should peak between -1.0 and -1.2...late SOI response will hold it back.

[40/70 Benchmark]

1 hour ago, snowman19 said:

Winter forecasts have been in constant fail mode since the 15-16 winter because of the MJO/West PAC marine heatwave and the strong -PDO. 

‘

Real curious to see what the MEI does this month….with the 30 day SOI near +5, the increasingly negative PDO, developing -PMM, cooling/increased trades in region 3.4, falling IOD (at -0.07), Niña forcing reflected in the global OLR…a very well coupled system is in place. Let’s see if the new MEI reflects this….  ‘

I did well with 2016-2017, 2017-2018, 2020-2021 and 2021-2022.

[40/70 Benchmark]

55 minutes ago, snowman19 said:

Besides the PDO, solar/geomag and ACE not matching, 2017 was also -QBO, it was a very east-based La Niña and there was no New Foundland warm pool, the +AMO configuration was completely different. The MJO behavior back then also doesn’t match this year. Why BAMWX is saying it’s a good analog is totally beyond me

Its a great ONI analog...the best IMO.

[40/70 Benchmark]

3 hours ago, raindancewx said:

He's just using the SST matching tool from Tropical Tidbits but this is similar overall to my thoughts on the winter. Haven't written my forecast yet though. I do think the Atlantic ridging will setup somewhat west of where he shows it though.

https://www.tropicaltidbits.com/analysis/hsanalog/

I don't like 2017 as an analog - it's the most active September hurricane season since 1850, with low solar and weakly positive PDO conditions. The other years are high solar, and less active hurricane seasons with more -PDO conditions. ACE has to be 50% above normal for the rest of the season to catch up to normal. My rule is ~95%+ of seasons will finish between June-Sept and June-Sept + 60 ACE. To me it's about 50/50 that we'll hit 90 ACE.

I'm not sure what he is smoking with the east-based la Nina claim...its been rapidly shiftng for awhile now.

[Stormchaserchuck1]

PDO correlation is really working

[CurlyHeadBarrett]

7 hours ago, PhiEaglesfan712 said:

First year la ninas that were misses

1970 (2nd year la nina 1971 was near average)

1973 (2nd year la nina 1974 was below average)

1983 (2nd year la nina 1984 was near average)

2007 (2nd year la nina 2008 was active)

 

And the 70s and 80s seasons were in a cold phase anyway

[Stormchaserchuck1]

18 hours ago, donsutherland1 said:

Climate change is influencing patterns, particularly from large-scale marine heatwaves. The current PDO- is one example. The increased frequency of the MJO's residing in the Marine Continent phases is another. That's why some seasonal forecasting methodologies based largely on analogs (even when the variables closely fit) now consistently perform poorly.

Why were the 1980s and 90s +PDO?  We also just had a healthy +PDO not too long ago from '14-16. 

I don't think seasonal forecasts are doing bad.. the -PDO/Strong El Nino composite worked about perfectly for N. America last Winter. 

[donsutherland1]

3 hours ago, Stormchaserchuck1 said:

Why were the 1980s and 90s +PDO?  We also just had a healthy +PDO not too long ago from '14-16. 

I don't think seasonal forecasts are doing bad.. the -PDO/Strong El Nino composite worked about perfectly for N. America last Winter. 

Not all, but some seasonal forecast methodologies are failing. On Social Media, there were several winter forecasts that assumed, for example, that the East would be cold and snowy (it was again much warmer than normal with much lower than normal snowfall).  CPC did well.

The North Pacific marine heatwave is impacting PDO. That marine heatwave wasn't around in the 1980s or 1990s. Moreover, the likelihood of such a heatwave is much greater today than it was then.

[PhiEaglesfan712]

4 hours ago, Stormchaserchuck1 said:

Why were the 1980s and 90s +PDO?  We also just had a healthy +PDO not too long ago from '14-16. 

I don't think seasonal forecasts are doing bad.. the -PDO/Strong El Nino composite worked about perfectly for N. America last Winter. 

I don't think there was a -PDO/strong el nino combo in the past 75 years. The closest ones were 1965-66, 1972-73, and 2009-10, and all were close enough 0 PDO during the el nino event (although 1972-73 and 2009-10 were surrounded by multi-year la ninas, and were deeper -PDOs outside of the el nino event).

1965 -0.95 -0.61 -0.17 -0.01 -0.66 -0.76 -0.74  0.32  0.83  0.30  0.47  0.25
1966 -0.67 -0.43 -1.00 -0.37 -0.76  0.10  0.01 -0.29 -0.35 -0.60 -0.71 -0.21

1972 -2.12 -1.95 -1.53 -1.70 -2.16 -1.84 -1.48 -0.11 -0.20 -0.22 -0.05 -0.37
1973 -0.15 -0.55 -0.88 -1.35 -1.59 -1.44 -1.40 -1.56 -1.05 -1.36 -1.42 -0.89

2009 -1.81 -1.78 -2.06 -2.23 -1.32 -0.73 -0.71 -0.49  0.33 -0.13 -0.94 -0.51
2010  0.05  0.25 -0.16 -0.04 -0.18 -0.79 -1.99 -2.21 -2.45 -1.60 -1.57 -2.04

Those three years produced one that was bitter cold (1965-66), one that was snowless (1972-73), and one that was the snowiest winter of all-time (2009-10) here at PHL. 2023-24 was none of that, but rather one of the warmest winters at PHL. Proof that a strong el nino is more of a wild card more than anything.

[snowman19]

5 hours ago, 40/70 Benchmark said:

I'm not sure what he is smoking with the east-based la Nina claim...its been rapidly shiftng for awhile now.

The east-based Niña fantasies on twitter are going to go down in flames 

[GaWx]

2 hours ago, donsutherland1 said:

Not all, but some seasonal forecast methodologies are failing. On Social Media, there were several winter forecasts that assumed, for example, that the East would be cold and snowy (it was again much warmer than normal with much lower than normal snowfall).  CPC did well.

The North Pacific marine heatwave is impacting PDO. That marine heatwave wasn't around in the 1980s or 1990s. Moreover, the likelihood of such a heatwave is much greater today than it was then.

What do you think about this from Eric Webb about what he calls very warm water centered on 150E?  @bluewave@snowman19and others. Eric has had big busts before in winter forecasts though. So, I take him with a grain like I do most.

“Why is the warmth ~150°E in the Tropical West Pacific important? Anomalous Tropical West Pacific warmth normally favors more frequent high-latitude blocking (-EPO/-WPO) over the North Pacific rim during the winter.”

 

[snowman19]

What do you think about this from Eric Webb about what he calls very warm water centered on 150E?  [mention=564]bluewave[/mention][mention=13098]snowman19[/mention]and others. Eric has had big busts before in winter forecasts though. So, I take him with a grain like I do most.
“Why is the warmth ~150°E in the Tropical West Pacific important? Anomalous Tropical West Pacific warmth normally favors more frequent high-latitude blocking (-EPO/-WPO) over the North Pacific rim during the winter.”
[/url]  

Eric has done horribly the last 3 winters in a row. He also says he doubts it happens given the extratropical (very strong -PDO) synoptic picture:

-ENSO/-IOD very strongly favors Maritime Continent and eastern IO forcing. How many times are we going to forecast MJO 8, 1, 2 forcing only to have it fail? We tried this exact same thing last year and all we saw was MJO 4-6 all winter and that was during an El Niño no less

[40/70 Benchmark]

2 hours ago, PhiEaglesfan712 said:

I don't think there was a -PDO/strong el nino combo in the past 75 years. The closest ones were 1965-66, 1972-73, and 2009-10, and all were close enough 0 PDO during the el nino event (although 1972-73 and 2009-10 were surrounded by multi-year la ninas, and were deeper -PDOs outside of the el nino event).

1965 -0.95 -0.61 -0.17 -0.01 -0.66 -0.76 -0.74  0.32  0.83  0.30  0.47  0.25
1966 -0.67 -0.43 -1.00 -0.37 -0.76  0.10  0.01 -0.29 -0.35 -0.60 -0.71 -0.21

1972 -2.12 -1.95 -1.53 -1.70 -2.16 -1.84 -1.48 -0.11 -0.20 -0.22 -0.05 -0.37
1973 -0.15 -0.55 -0.88 -1.35 -1.59 -1.44 -1.40 -1.56 -1.05 -1.36 -1.42 -0.89

2009 -1.81 -1.78 -2.06 -2.23 -1.32 -0.73 -0.71 -0.49  0.33 -0.13 -0.94 -0.51
2010  0.05  0.25 -0.16 -0.04 -0.18 -0.79 -1.99 -2.21 -2.45 -1.60 -1.57 -2.04

Those three years produced one that was bitter cold (1965-66), one that was snowless (1972-73), and one that was the snowiest winter of all-time (2009-10) here at PHL. 2023-24 was none of that, but rather one of the warmest winters at PHL. Proof that a strong el nino is more of a wild card more than anything.

The reason for the variation is due to both the differences in placement of each el nino in terms of max anomalies relative to the entire Pacific basin...the ongoinf huge west pac warn pool is related to why none of those seasons had had nearly as deep a -PDO. Pretty clear that 1972 was by far the best march of the 3 in hindsight. I got that wrong and have learned a great deal from it.

[40/70 Benchmark]

2 hours ago, snowman19 said:

The east-based Niña fantasies on twitter are going to go down in flames 

I will say that it doesn't matter as much with a weaker La Nina....2008 was a weaket Modoki La Nina with a -PDO and very favorable north Pac....not a horrible analog. The cool ENSO walker cell will not be completley overwhelming like it was two years ago.

[PhiEaglesfan712]

9 minutes ago, 40/70 Benchmark said:

I will say that it doesn't matter as much with a weaker La Nina....2008 was a weaket Modoki La Nina with a -PDO and very favorable north Pac....not a horrible analog. The cool ENSO walker cell will not be completley overwhelming like it was two years ago.

I'll take 2008-09 any day over 2022-23. I just wish the cold and snow would have aligned. At least in 08-09, we got a cold October-January, and the big snowstorms in early February and March 1-2. I think we also got a snow event in mid-November.

[donsutherland1]

49 minutes ago, GaWx said:

What do you think about this from Eric Webb about what he calls very warm water centered on 150E?  @bluewave@snowman19and others. Eric has had big busts before in winter forecasts though. So, I take him with a grain like I do most.

“Why is the warmth ~150°E in the Tropical West Pacific important? Anomalous Tropical West Pacific warmth normally favors more frequent high-latitude blocking (-EPO/-WPO) over the North Pacific rim during the winter.”

 

It's a factor to watch. However, at this time, I suspect that the very strongly negative PDO will have a larger impact on the pattern, which would impede a deep or sustained EPO-.

[40/70 Benchmark]

8 minutes ago, PhiEaglesfan712 said:

I'll take 2008-09 any day over 2022-23. I just wish the cold and snow would have aligned. At least in 08-09, we got a cold October-January, and the big snowstorms in early February and March 1-2. I think we also got a snow event in mid-November.

I'm sure it won't be thst cold due to the west Pac warm pool in conjunction with overall CC, but it should be better than last year. Hopefully we get some amplified MC MJO acitivty in October per Bluewave to confirm my suspicion of some periods of disconnect from that wretched west Pac warmth.

[40/70 Benchmark]

7 minutes ago, donsutherland1 said:

It's a factor to watch. However, at this time, I suspect that the very strongly negative PDO will have a larger impact on the pattern, which would impede a deep or sustained EPO-.

I think something like 20-21 and 21-22 is attainable. 

[snowman19]

3 minutes ago, 40/70 Benchmark said:

I think something like 20-21 and 21-22 is attainable. 

I’m not a fan of 20-21 at all. That was a solar minimum 

[donsutherland1]

33 minutes ago, 40/70 Benchmark said:

I think something like 20-21 and 21-22 is attainable. 

I suspect 2021-22 will probably offer better insight, but it's still early.

[user13]

2 minutes ago, donsutherland1 said:

I suspect 2021-22 will probably offer better insight, but it's still early.

For sure don

[qg_omega]

Mjo will be lopping 456 all winter, nothing else really matters

[mitchnick]

1 hour ago, snowman19 said:

Eric has done horribly the last 3 winters in a row. He also says he doubts it happens given the extratropical (very strong -PDO) synoptic picture:

 

 

 

-ENSO/-IOD very strongly favors Maritime Continent and eastern IO forcing. How many times are we going to forecast MJO 8, 1, 2 forcing only to have it fail? We tried this exact same thing last year and all we saw was MJO 4-6 all winter and that was during an El Niño no less

 

 

Good time now to test MJO forecasting because just about every model has it going into the W. Hemisphere and Africa over the coming weeks.

https://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/ncpe.shtml

[donsutherland1]

Today, the NAO fell to -1.900, which is very unusual for September. Since 1950, there have been three La Niña winters that followed such outcomes (1971-72, 2016-17, and 2022-23). All three favored a predominantly positive NAO during the winter. All three winters also favored warmer than normal winters in the eastern third to half of the CONUS. 2022-23 had solar activity that is most consistent with what is likely during the upcoming winter. Winter 2016-17 followed a strong El Niño winter, but the PDO was positive (very unlikely this time around).

The composite for the two most recent winters (selected because they fall in the contemporary climate regime):

For comparison, the latest C3S multi-model and CPC outlooks follow:

C3S:

CPC:

It's early, so the C3S, which did well last winter from this timeframe (but hasn't always fared as well, might be aggressive and overly expansive with the warmth. For example, the Great Lakes Region (Chicago to Toronto) might wind up milder than normal, but not excessively so, with normal to somewhat above normal snowfall. Overall, the latest NMME (9/8 0z initialization) has an outlook that closely resembles the anomaly patter (but not necessarily the values) shown on the C3S. The CFSv2 offers a sort of compromise between the CPC outlook and the C3S.

[bluewave]

2 hours ago, GaWx said:

centered on 150E?

The record SST warmth is much more expansive than just 150E. It encompasses the entire area from the Maritime Continent to around the Dateline. The +30C warm pool area is much larger than anything we have ever seen before. The previous record holder was the summer of 2016. But you can see this summer was a leap above the levels heading into the 16-17 La Niña winter.

 

 

[Typhoon Tip]

11 hours ago, snowman19 said:

Winter forecasts have been in constant fail mode since the 15-16 winter because of the MJO/West PAC marine heatwave and the strong -PDO. 

‘

Real curious to see what the MEI does this month….with the 30 day SOI near +5, the increasingly negative PDO, developing -PMM, cooling/increased trades in region 3.4, falling IOD (at -0.07), Niña forcing reflected in the global OLR…a very well coupled system is in place. Let’s see if the new MEI reflects this….  ‘

is it a 'heat wave' or more permanent - marine heatwave phenomenon have shelf lives.   this is beginning to feel like something in the scaffolding of the planet do the weight of persistence - just supposition speaking.

2ndly,  are we certain that the west pac is why seasons are not behaving :   i understand the appeal of finding a silver bullet cause but i'm just as curious that the weird winter thing and the west pac may both be resulting and not necessarily causally linked like that.  

[40/70 Benchmark]

1 hour ago, snowman19 said:

I’m not a fan of 20-21 at all. That was a solar minimum 

I'm just talking about the deviation from the west PAC forcing and the influence on sensible weather. That said, I don't see wall-to-wall juggernaut PV, either.

[FPizz]

2 hours ago, snowman19 said:

Eric has done horribly the last 3 winters in a row. He also says he doubts it happens given the extratropical (very strong -PDO) synoptic picture:

 

 

 

-ENSO/-IOD very strongly favors Maritime Continent and eastern IO forcing. How many times are we going to forecast MJO 8, 1, 2 forcing only to have it fail? We tried this exact same thing last year and all we saw was MJO 4-6 all winter and that was during an El Niño no less

 

 

Agreed, he mentions everything so he's never wrong and when you question him, he blocks you.  Typical X met that's never had a real job