2024-2025 La Nina

[Terpeast]

2 hours ago, GaWx said:

 I’m saying that regarding peak strength 2023-4 and despite similar ONI, I don’t think of 2023-4 as comparable to 2015-6 and 1997-8 due to a much cooler RONI. Therefore, I wouldn’t expect the 2023-4 SOIs to be anywhere near as negative as those for the other two. The other two dipped to as low as -20s for monthly SOI vs 2023-4 dipping to only the -10s. Thus I’m not surprised.

 When comparing to other Ninos of similar strength, I prefer to look at RONI. So, I looked back to 1950 to see what other El Niños had a RONI peak similar to 2023-4’s +1.49 peak. That’s when I found these with similar peak:

2009-10: +1.57

2002-3: +1.46

1994-5: +1.44 (I inadvertently left this out)

1986-7: +1.54

  That’s all I meant by them being “close”. Close in RONI strength. I’m not saying they were necessarily close in any other way except for lowest SOI months as these 4 had lowest months in the -10s just like 2023-4, which makes sense from a RONI based strength point of view.

 

I am starting to think that the difference between ONI and RONI should be a factor in and of itself when thinking about seasonal outlooks. I don’t think that we had a 0.6 difference in ONI vs RONI for 86-87 and 09-10…

[snowman19]

Just out of curiosity for comparison to this year, (obviously current anomalies like the ++AMO, record low arctic sea ice, AGW and extreme WPAC/Atlantic warm pools are not going to be able to be found). But if someone can lookup any years that were the following: La Niña (non east-based events), strong -PDO, -PMM, +QBO, -IOD, +AMO, MJO 4-6 dominant, high solar/high geomag. Also, if any years had all those factors and were also volcanic. Thank you

[PhiEaglesfan712]

31 minutes ago, Terpeast said:

I am starting to think that the difference between ONI and RONI should be a factor in and of itself when thinking about seasonal outlooks. I don’t think that we had a 0.6 difference in ONI vs RONI for 86-87 and 09-10…

If I remember correctly, the RONI and ONI were almost in line in 2009-10. The 86-87 one was weird. The RONI had a double peak, while the ONI peaked in the summer.

 JJA 1986   RONI: 0.25 ONI: 0.3
 JAS 1986   RONI: 0.55 ONI: 0.6
 ASO 1986   RONI: 0.87 ONI: 0.9
 SON 1986   RONI: 1.12 ONI: 1.1
 OND 1986   RONI: 1.35 ONI: 1.2
 NDJ 1986   RONI: 1.49 ONI: 1.2
 DJF 1987   RONI: 1.54 ONI: 1.2 - First RONI (winter) peak
 JFM 1987   RONI: 1.43 ONI: 1.2
 FMA 1987   RONI: 1.17 ONI: 1.1
 MAM 1987   RONI: 0.87 ONI: 1.0
 AMJ 1987   RONI: 0.77 ONI: 1.1
 MJJ 1987   RONI: 0.94 ONI: 1.3
 JJA 1987   RONI: 1.23 ONI: 1.6
 JAS 1987   RONI: 1.46 ONI: 1.7 - Second RONI (summer) peak
 ASO 1987   RONI: 1.43 ONI: 1.8 - ONI peak
 SON 1987   RONI: 1.24 ONI: 1.7 
 OND 1987   RONI: 1.02 ONI: 1.4
 NDJ 1987   RONI: 0.93 ONI: 1.1
 DJF 1988   RONI: 0.65 ONI: 0.7
 JFM 1988   RONI: 0.30 ONI: 0.3

So, the RONI began and ended the el nino at roughly the same. In between, the RONI was ahead by as much as .34 over the ONI in the winter. This would flip flop during the year, as the ONI ended up ahead as much as .46 over the RONI by the fall.

Of course, when this el nino dissipated, it transitioned into a strong la nina in 1988-89 (just as the 2009-10 strong el nino transitioned into the 2010-11 strong la nina).

[Stormchaserchuck1]

4 hours ago, snowman19 said:

Just out of curiosity for comparison to this year, (obviously current anomalies like the ++AMO, record low arctic sea ice, AGW and extreme WPAC/Atlantic warm pools are not going to be able to be found). But if someone can lookup any years that were the following: La Niña (non east-based events), strong -PDO, -PMM, +QBO, -IOD, +AMO, MJO 4-6 dominant, high solar/high geomag. Also, if any years had all those factors and were also volcanic. Thank you

99-00 is probably your best match, but you aren't going to find anything that fits all of that. A lot of recent analogs are closer to your guidelines than older ones.. 

[40/70 Benchmark]

12 hours ago, GaWx said:

 I’m saying that regarding peak strength 2023-4 and despite similar ONI, I don’t think of 2023-4 as comparable to 2015-6 and 1997-8 due to a much cooler RONI. Therefore, I wouldn’t expect the 2023-4 SOIs to be anywhere near as negative as those for the other two. The other two dipped to as low as -20s for monthly SOI vs 2023-4 dipping to only the -10s. Thus I’m not surprised.

 When comparing to other Ninos of similar strength, I prefer to look at RONI. So, I looked back to 1950 to see what other El Niños had a RONI peak similar to 2023-4’s +1.49 peak. That’s when I found these with similar peak:

2009-10: +1.57

2002-3: +1.46

1994-5: +1.44 (I inadvertently left this out)

1986-7: +1.54

  That’s all I meant by them being “close”. Close in RONI strength. I’m not saying they were necessarily close in any other way except for lowest SOI months as these 4 had lowest months in the -10s just like 2023-4, which makes sense from a RONI based strength point of view.

 

I know what you meant, I was just adding to it.

[40/70 Benchmark]

5 hours ago, Stormchaserchuck1 said:

99-00 is probably your best match, but you aren't going to find anything that fits all of that. A lot of recent analogs are closer to your guidelines than older ones.. 

Yup. High up on my list.

[40/70 Benchmark]

10 hours ago, Terpeast said:

I am starting to think that the difference between ONI and RONI should be a factor in and of itself when thinking about seasonal outlooks. I don’t think that we had a 0.6 difference in ONI vs RONI for 86-87 and 09-10…

Seasons with a large discrepancy between the ONI and RONI underscrore the importance of looking at the hemispheric landscape beyond ENSO.

[bluewave]

21 hours ago, GaWx said:

Based on RONI peak, 2023-4 wasn’t even close to 15-6 and 97-8 and thus wasn’t that strong of an El Niño:

23-4: +1.49 moderate/strong border

15-6: +2.39 well into super

97-8: +2.36 well into super

 

 Based on RONI, 23-4 was close to 2009-10, 2002-3, and 1986-7:

https://www.cpc.ncep.noaa.gov/data/indices/RONI.ascii.txt

It’s how we got to the lower RONI with this borderline super El Niño event which made all the difference. The record WPAC warm pool in conjunction with the Nino 3.4 +2.0 ONI forcing combined to make 23-24 warmer than any previous super El Niño event for the CONUS. MJO 4-7 forcing with an El Niño produces very warm conditions over North America during the winter. We were lucky in 15-16 that the record MJO 4-7 forcing was only limited to the +13.3 December in the Northeast. When the typical Nino forcing was able to dominate things cooled off relative to December and became snowy. The 97-98 and 82-83 super El Niños were much cooler across the CONUS since the MJO wasn’t amplified in phases 4-7 due to the much cooler WPAC warm pool during those years. In addition, the -SOI peaked in 82-83 and has been getting weaker with each succeeding super El Niño event since then. Probably related to the rapidly warming WPAC relative to the Central and Eastern Pacific. Also the EQSOI is becoming more relevant due to the warming right along the equator near the Maritime Continent. 
 

Warmest U.S winter rankings showing how much warmer winters with +2.0 ONIs are getting 

#1….23-24…..37.53°

#2….15-16……36.78°

#8….97-98….35.90°

#15….82-83….35.27°

 

 

[40/70 Benchmark]

30 minutes ago, bluewave said:

It’s how we got to the lower RONI with this borderline super El Niño event which made all the difference. The record WPAC warm pool in conjunction with the Nino 3.4 +2.0 ONI forcing combined to make 23-24 warmer than any previous super El Niño event for the CONUS. MJO 4-7 forcing with an El Niño produces very warm conditions over North America during the winter. We were lucky in 15-16 that the record MJO 4-7 forcing was only limited to the +13.3 December in the Northeast. When the typical Nino forcing was able to dominate things cooled off relative to December and became snowy. The 97-98 and 82-83 super El Niños were much cooler across the CONUS since the MJO wasn’t amplified in phases 4-7 due to the much cooler WPAC warm pool during those years. In addition, the -SOI peaked in 82-83 and has been getting weaker with each succeeding super El Niño event since then. Probably related to the rapidly warming WPAC relative to the Central and Eastern Pacific. Also the EQSOI is becoming more relevant due to the warming right along the equator near the Maritime Continent. 
 

Warmest U.S winter rankings showing how much warmer winters with +2.0 ONIs are getting 

#1….23-24…..37.53°

#2….15-16……36.78°

#8….97-98….35.90°

#15….82-83….35.27°

 

 

Exactly what I have been getting at....much like mathamatics, its not about the final solution but hot it is arrived at that matters.

[snowman19]

Not saying it’s right, but the new NMME has the Niña developing as a central-based event….

[GaWx]

Taking its sweet time:

[snowman19]

Taking its sweet time:

[snowman19]

3 hours ago, snowman19 said:

 

 

Just to add, if the models are correct about where the EWB is going to be taking place, it would lend some credibility to the NMME idea of this La Niña being region 3.4 centered

[Stormchaserchuck1]

7 hours ago, GaWx said:

Taking its sweet time:

Yeah.. probably won't be a La Nina next year. 

[Maestrobjwa]

9 minutes ago, Stormchaserchuck1 said:

Yeah.. probably won't be a La Nina next year. 

How can ya say that when all of the recent ones have been 2+ years? And in general don't most of them double dip?

[Stormchaserchuck1]

11 minutes ago, Maestrobjwa said:

How can ya say that when all of the recent ones have been 2+ years? And in general don't most of them double dip?

The western subsurface is building warm anomalies, and the 90-day SOI is -9. I mean, it is possible, but the trends for the following year usually start to post clues around this time. That Nino 4 is still warm-Neutral kind of puts Winter potential Kelvin waves into play. Remember, most ENSO events peak only a few months from now, and El Nino to Neutral isn't usually followed up by a La Nina (it may still be Weak Nina, but the "swing" after a Strong El Nino usually sets the tone in the 1st year). Maybe I'm rushing the warming train (El Nino probabilities a few years from now).. 

[Stormchaserchuck1]

In other news, the North Pacific High near the Aleutian islands looks to be strong for the next 15 days on models.. Will continue to strengthen the -PDO. 

Not coincidentally, this is occurring while the central-ENSO-subsurface is in "Moderate La Nina" range

[Stormchaserchuck1]

11 hours ago, 40/70 Benchmark said:

Yup. High up on my list.

22-23 would probably be #2 on his list 

[Stormchaserchuck1]

10 hours ago, bluewave said:

Warmest U.S winter rankings showing how much warmer winters with +2.0 ONIs are getting 

#1….23-24…..37.53°

#2….15-16……36.78°

#8….97-98….35.90°

#15….82-83….35.27°

It's been because of a +WPO/+EPO though, which isn't necessarily an El Nino indicator.. although maybe for east-based events.. 5 of the last 6 Winters have been +WPO. This is a cold weather anomaly over the Bering Strait region. 

[PhiEaglesfan712]

1 hour ago, Stormchaserchuck1 said:

Yeah.. probably won't be a La Nina next year. 

I've been saying that the anti-86/87 scenario could occur, and the la nina could peak as a strong one in summer 2025. (Just don't expect it do dissipate really quickly in the winter of 2025-26, and transition into a super el nino in 2026-27.)

I'd assume a summer peaking strong la nina would be very hot and dry in the East, and most of the United States, for that matter. The closest thing to strong la nina conditions in the summer was 1988 (heading into the historical la nina), following the dissipation of the el nino that began in 1986. 

[Stormchaserchuck1]

50 minutes ago, PhiEaglesfan712 said:

I've been saying that the anti-86/87 scenario could occur, and the la nina could peak as a strong one in summer 2025. (Just don't expect it do dissipate really quickly in the winter of 2025-26, and transition into a super el nino in 2026-27.)

I'd assume a summer peaking strong la nina would be very hot and dry in the East, and most of the United States, for that matter. The closest thing to strong la nina conditions in the summer was 1988 (heading into the historical la nina), following the dissipation of the el nino that began in 1986. 

We'll see.. if it's La Nina this year, that will make 4/5 years with La Nina (which is the most consecutive going back to 1948). 

86-88 was at the peak of +PDO phase so I'll give you that

We have also had 7 +NAO bouts so far this year, where for the last 4 years, it was 2-3. That could possibly signal a phase shift.. The NAO is looking not so positive for August and possibly September though. 

[bluewave]

12 hours ago, Stormchaserchuck1 said:

It's been because of a +WPO/+EPO though, which isn't necessarily an El Nino indicator.. although maybe for east-based events.. 5 of the last 6 Winters have been +WPO. This is a cold weather anomaly over the Bering Strait region. 

My guess is that the +WPO last winter was a function of the MJO 7 dominant forcing in conjunction with record -PDO and marine heatwave east of Japan. These features strengthened the Nino ridge over Canada and weakened the Nino trough over the Southeast. So the warmer temperatures in the East reflected the -PDO Aleutian ridge north of Hawaii and stronger downstream ridge in the East. These two were more La Niña-like features. So last winter was a combination of the warmest El Niño and La Niña influences for the U.S. it’s why it was the warmest winter on record for the CONUS.

[40/70 Benchmark]

16 hours ago, Stormchaserchuck1 said:

22-23 would probably be #2 on his list 

Also on  my short list.

[TriPol]

If a La Nina is scheduled to develop, we might have a late tropical season. Should be interesting to follow.

[GaWx]

 The models are suggesting a shot at the highest daily SOIs in 2 yrs with +35+ possible in 7-10 days. This is largely due to strong HP S of Tahiti. The GFS suite is saying there could be a 1019+ peak there though others are ~1018.

[PhiEaglesfan712]

I don't like the 22-23 analog at all. That was a 3rd year nina that pretty much peaked in the summer and dissipated during the winter. Plus, that one had a warm subsurface.

This is pretty much an opposite set-up to what we have this year. Now, if we have the scenario where a strong la nina peaks next summer, I'd use it as an analog for 2025-26. But definitely not a good analog for this year.

[snowman19]

2 hours ago, GaWx said:

 The models are suggesting a shot at the highest daily SOIs in 2 yrs with +35+ possible in 7-10 days. This is largely due to strong HP S of Tahiti. The GFS suite is saying there could be a 1019+ peak there though others are ~1018.

Finally a major (positive) SOI response consistent with a developing -ENSO. Here is the EURO-UKMET super blend SST map for November. As you can see, the event is concentrated in region 3.4:

 

 

 

 

[Stormchaserchuck1]

1 hour ago, PhiEaglesfan712 said:

I don't like the 22-23 analog at all. That was a 3rd year nina that pretty much peaked in the summer and dissipated during the winter. Plus, that one had a warm subsurface.

I actually thought that Winter 22-23 would be cooler than it was. It was one of those years where the subsurface wasn't accurate.. nothing is perfect, but over a larger amount of data, it does work better than the surface, and even the PDO. 

[Stormchaserchuck1]

LR GEFS is flexing a ridge east of Japan again, near that warm pool region. 

The US pattern in evolution would favor more GOM or FL hurricane hits, as that central Canada ridge moves east with a -PNA. central-N. Atlantic ridge is strong on the mean. If we see African waves progress, they would likely move more westward at this time. 

[snowman19]

@Bluewave Besides the central-based La Niña and continuation of the strong +AMO it’s showing come November, look at how severely negative the PDO gets, the WPAC warm pool is crazy on this new run. Also, has the -PMM continuing and the new climate model runs are getting stronger with the -IOD come October