2024-2025 La Nina

[George001]

3 hours ago, 40/70 Benchmark said:

That is my hope for next year....I think that would be a bullish signal for next winter.

Hopefully it stays weak if a Nino does develop.

[snowman19]

19 hours ago, GaWx said:

 Well, this changed on today’s Euro Weeklies as there are many members with a major SSW within Mar 9-14 (see below). This is easily the most bullish run this winter. If this occurs, this may mean a chilly April in much of the E US. This would jibe well with Joe D’Aleo’s research on its connection with +QBO/high solar and Ray’s feeling there’d likely be one late this winter.

@40/70 Benchmark

@snowman19

 

Here’s the 12Z Euro op 360 10 mb temp anomalies:

Maybe it’ll actually happen this time unlike the phantom, hyped 2018 major SSW/SPV split for mid-February. Even if one was to happen in mid-March, way too little, too late for winter. With the lag, we will be into astronomical spring by the time any of it has any effect. Besides that, it’s right around the time we normally have a “final warming” from the increased solar radiation as we move into spring. Color me unimpressed. As far as Joe D’Aleo, if it happens, it would seem he was definitely onto something, yes

[so_whats_happening]

Impressive changes in the PDO state over the last 3 months of SSTA. Here was the associated 500mb pattern during this time, certainly was not expecting a look like this. It is interesting to watch the PDO state try to change still unsure myself what exactly kicked off this chain reaction from constant ridging in the WPAC. In my opinion there still seems to be a disconnect between tropics and mid latitude that we would have such a strong -PDO during the Nino last year (strong/super) and to have not quite flipped but weakened significantly the -PDO with a Nina state. I still don't think we see a tri monthly below -.5 and this Nina may just get one blue numbering for trimonthly (NDJ), even I thought around -1.0 was possible this go around.

Lastly, it is interesting seeing the 500mb pattern across the Pacific with the more latitudinal shift just NW of Hawaii, I believe bluewave has touched on this several times. The waters across the Pacific must have just been far too warm a lot of it seemingly just shoved further east and south. It will be interesting to see if there are lagging effects of the Nina across the Atlantic this summer for the hurricane season.

[LibertyBell]

4 hours ago, 40/70 Benchmark said:

The "bottom up" split earlier this month, on the 10th, certainly was a curveball that biased the month colder. But this would be more in line with my original expectation.

Isn't an early April snowstorm indicative of an el nino the following winter?

April 1982 and April 1997 are examples.

[GaWx]

48 minutes ago, snowman19 said:

Maybe it’ll actually happen this time unlike the phantom, hyped 2018 major SSW/SPV split for mid-February. Even if one was to happen in mid-March, way too little, too late for winter. With the lag, we will be into astronomical spring by the time any of it has any effect. Besides that, it’s right around the time we normally have a “final warming” from the increased solar radiation as we move into spring. Color me unimpressed. As far as Joe D’Aleo, if it happens, it would seem he was definitely onto something, yes

And GEFS still had no signal for a major SSW as of yest:

[LibertyBell]

On 2/21/2025 at 11:27 AM, snowman19 said:

Different year, same ending with him. He does this every single March for subscription money, attention, likes, views, follows and retweets. It’s like the movie Groundhog Day. He’s The Boy Who Cried Wolf, zero credibility anymore

I was wondering where all this excitement about a March snowstorm came from. Maybe it's just his subscribers lol.

[40/70 Benchmark]

34 minutes ago, LibertyBell said:

Isn't an early April snowstorm indicative of an el nino the following winter?

April 1982 and April 1997 are examples.

Weenie folklore

[40/70 Benchmark]

1 hour ago, snowman19 said:

Maybe it’ll actually happen this time unlike the phantom, hyped 2018 major SSW/SPV split for mid-February. Even if one was to happen in mid-March, way too little, too late for winter. With the lag, we will be into astronomical spring by the time any of it has any effect. Besides that, it’s right around the time we normally have a “final warming” from the increased solar radiation as we move into spring. Color me unimpressed. As far as Joe D’Aleo, if it happens, it would seem he was definitely onto something, yes

What was phantom?? That 2018 event verified quite strongly....this past February wasn't a SSW. The PV split definitely occurred, but it was born of lower level processes and definitely induced a cold pattern. 

[40/70 Benchmark]

1 hour ago, George001 said:

Hopefully it stays weak if a Nino does develop.

I think it would.

[40/70 Benchmark]

I think referring to the PV split as a phantom event because it didn't result in an east coast blizzard is pretty silly.

[snowman19]

8 minutes ago, 40/70 Benchmark said:

What was phantom?? That 2018 event verified quite strongly....this past February wasn't a SSW. The PV split definitely occurred, but it was born of lower level processes and definitely induced a cold pattern. 

You misread me. I’m referring to the one that didn’t happen this February. Remember all the hypesters saying it was going to be exactly like 2018?

[40/70 Benchmark]

17 minutes ago, snowman19 said:

You misread me. I’m referring to the one that didn’t happen this February. Remember all the hypesters saying it was going to be exactly like 2018?

I was comparing the split to 2018 and it was similar in the sense that it funneled ample cold into the eastern US...as you know, some of these PV disruptions send all of the cold to the other side of the globe. The big NE snows not working out is more due to issues with the western ridge...nothing to do with the PV split.

[PhiEaglesfan712]

3 hours ago, George001 said:

Hopefully it stays weak if a Nino does develop.

Thing is, the WPAC and the EPAC are so disjointed now. If any type of el nino forms in WPAC, even a weak one, the EPAC is almost certainly going to be in a strong el nino state.

For us to have a weak el nino, the WPAC probably has to be near ENSO neutral.

[roardog]

Considering we just had a super Nino last winter, I can’t believe we would have another strong Nino this soon.

[LibertyBell]

5 hours ago, 40/70 Benchmark said:

Weenie folklore

I thought you were the one who said that years ago.... it was you or Will, I can't remember who.

[GaWx]

9 hours ago, LibertyBell said:

Isn't an early April snowstorm indicative of an el nino the following winter?

April 1982 and April 1997 are examples.

You got me curious. So, I checked NYC data for 1”+ snowstorms during Apr 1-10 at NYC, JFK, or LGA. I found 24 storms:

Date…Snow…Station…Concurrent ENSO…Subsequent ENSO

4/2/2018 5.5” NYC L E

4/5/2006 1.0” JFK L E

4/7/2003 5.6” LGA E N

4/9/2000 1.2” NYC L L

4/1/1997 1.5” JFK N E

4/9-10/1996 4.0” JFK L N

4/6/1982 9.6” NYC N E

4/6/1971 3.2” JFK L L

4/2/1965 1.2” NYC L E

4/4/1957 5.4” LGA N E

4/8/1956 6.4” LGA L N

4/5/1944 6.5” NYC N N

4/6-7/1938 6.4” NYC N L

4/1/1924 8.5” NYC E L

4/9/1917 6.4” NYC L E

4/8-9/1916 3.3” NYC N L

4/3-4/1915 10.2” NYC E N

4/9/1907 5.0” NYC N N

4/5/1898 2.5” NYC N N

4/6-7/1896 3.0” NYC N E

4/1-2/1887 2.0” NYC L E

4/4-5/1886 1.0” NYC E L

4/2/1871 2.0” NYC N N

4/4/1870 2.5” NYC L N

————————————

Analysis of these 24:

-9 lead to El Niño

-9 lead to neutral

-6 lead to La Niña

-Only 4 concurrent El Niño

-10 concurrent with each of neutral and La Niña

-Of 10 La Niña: 5 went to El Niño, 3 went to neutral, and 2 remained La Niña

————————————

Conclusion:

 -With 5 of 10 of these La Niñas leading to El Niño and 9 of the entire 24 leading to El Nino, the stats say that an early April NYC snowstorm isn’t strongly indicative of El Niño the following winter. 

 -HOWEVER: Of the last 46 La Ninas, only 12 (26%) went to El Niño. (16 went to neutral and 18 remained La Niña). Of the 10 La Ninas with an early April NYC snowstorm, 5 (50% or ~twice the overall %) went to El Niño. That means that of the 36 La Ninas without a snowstorm, only 7 (19%) went to El Niño. So, perhaps having a La Niña snowstorm is indicative of a higher than normal chance for El Niño to follow La Niña.

[40/70 Benchmark]

11 hours ago, LibertyBell said:

I thought you were the one who said that years ago.... it was you or Will, I can't remember who.

I don't think so.

[LibertyBell]

9 hours ago, GaWx said:

You got me curious. So, I checked NYC data for 1”+ snowstorms during Apr 1-10 at NYC, JFK, or LGA. I found 24 storms:

Date…Snow…Station…Concurrent ENSO…Subsequent ENSO

4/2/2018 5.5” NYC L E

4/5/2006 1.0” JFK L E

4/7/2003 5.6” LGA E N

4/9/2000 1.2” NYC L L

4/1/1997 1.5” JFK N E

4/9-10/1996 4.0” JFK L N

4/6/1982 9.6” NYC N E

4/6/1971 3.2” JFK L L

4/2/1965 1.2” NYC L E

4/4/1957 5.4” LGA N E

4/8/1956 6.4” LGA L N

4/5/1944 6.5” NYC N N

4/6-7/1938 6.4” NYC N L

4/1/1924 8.5” NYC E L

4/9/1917 6.4” NYC L E

4/8-9/1916 3.3” NYC N L

4/3-4/1915 10.2” NYC E N

4/9/1907 5.0” NYC N N

4/5/1898 2.5” NYC N N

4/6-7/1896 3.0” NYC N E

4/1-2/1887 2.0” NYC L E

4/4-5/1886 1.0” NYC E L

4/2/1871 2.0” NYC N N

4/4/1870 2.5” NYC L N

————————————

Analysis of these 24:

-9 lead to El Niño

-9 lead to neutral

-6 lead to La Niña

-Only 4 concurrent El Niño

-10 concurrent with each of neutral and La Niña

-Of 10 La Niña: 5 went to El Niño, 3 went to neutral, and 2 remained La Niña

————————————

Conclusion:

 -With 5 of 10 of these La Niñas leading to El Niño and 9 of the entire 24 leading to El Nino, the stats say that an early April NYC snowstorm isn’t strongly indicative of El Niño the following winter. 

 -HOWEVER: Of the last 46 La Ninas, only 12 (26%) went to El Niño. (16 went to neutral and 18 remained La Niña). Of the 10 La Ninas with an early April NYC snowstorm, 5 (50% or ~twice the overall %) went to El Niño. That means that of the 36 La Ninas without a snowstorm, only 7 (19%) went to El Niño. So, perhaps having a La Niña snowstorm is indicative of a higher than normal chance for El Niño to follow La Niña.

wow thanks this is excellent data, I've been looking to compile a list of April snowstorms myself and I think you captured all of them, the only one I can think of that isn't in this list was a small event that occurred in April 1990, was that under 1 inch?

 

edit-- Larry I think you missed April 1983 at JFK, it was JFK'S latest accumulating snowfall on record, they had 1.5"

also looks like April snowstorms were much more common in the past.... during the 1910s we had them 3 consecutive years!

[GaWx]

2 hours ago, LibertyBell said:

wow thanks this is excellent data, I've been looking to compile a list of April snowstorms myself and I think you captured all of them, the only one I can think of that isn't in this list was a small event that occurred in April 1990, was that under 1 inch?

 

edit-- Larry I think you missed April 1983 at JFK, it was JFK'S latest accumulating snowfall on record, they had 1.5"

also looks like April snowstorms were much more common in the past.... during the 1910s we had them 3 consecutive years!

 Thank you.

 -Yes, 4/7/1990 was under 1”. So, that’s why I excluded it.

 - Good find but I didn’t include the 4/18/1983 1.5” at JFK because it was after April 10th. I did only April 1-10 because you asked about early April snowstorms.

-Indeed, 3 in a row in 1910s! However, consider that 1996-2006 had 5 in 11 years! Before that the most on record within 11 or fewer years was only 4: 1907-1917 and 1915-1924.

[LibertyBell]

1 minute ago, GaWx said:

 Thank you.

 -Yes, 4/7/1990 was under 1”. So, that’s why I excluded it.

 - Good find but I didn’t include the 4/18/1983 1.5” at JFK because it was after April 10th. I did only April 1-10 because you asked about early April snowstorms.

-Indeed, 3 in a row in 1910s! However, consider that 1996-2006 had 5 in 11 years! Before that the most on record within 11 or fewer years was only 4: 1907-1917 and 1915-1924.

Oh I just meant any snowstorms at all in April, do you have a full list of all April events, Larry? Snowfall is very rare after April 10th, so there can't be many more to add.

It's interesting about the 1996-2006 period, we also had some very cold winters in that list-- 1995-96 and 2002-03 were both very cold and snowy from beginning to end here.

[GaWx]

5 hours ago, LibertyBell said:

Oh I just meant any snowstorms at all in April, do you have a full list of all April events, Larry? Snowfall is very rare after April 10th, so there can't be many more to add.

It's interesting about the 1996-2006 period, we also had some very cold winters in that list-- 1995-96 and 2002-03 were both very cold and snowy from beginning to end here.

1. It turns out I did miss a 4/1-10 at NYC:

 2.2” on 4/9-10/1942 E L

2. Additions for 1”+ April 11+:

-4/19/1983: 1.5” at JFK E L
-4/12/1959: 1.3” at LGA E N

Earlier ones were all NYC:
-4/14/1950: 1.9” L L
-4/12-13/1940: 1.8” E E
-1918 had 2.6” on 4/11-13 L E. That means there were 4 straight Aprils with 1”+ snowstorms in 1915-18!
-1887 had a 2nd one! 3” on 4/18
-1875 had two after 4/10!! 4/13-14: 10.0” and 4/25: 3.0” N N
 

(Aside: ATL’s latest on record is also on 4/25! That was in 1910.)

——————————
New tally:

Analysis of these 31 years:

-11 lead to El Niño

-11 lead to neutral

-9 lead to La Niña

-8 concurrent with El Niño

-11 concurrent with neutral

- 12 concurrent with La Niña

-Of 12 La Niña: 6 went to El Niño, 3 went to neutral, and 3 remained La Niña

Conclusion: no change

 -With 6 of 12 of these La Niñas leading to El Niño and 11 of the entire 31 leading to El Nino, the stats say that an April NYC snowstorm isn’t strongly indicative of El Niño the following winter. 

 -HOWEVER: Of the last 46 La Ninas, only 12 (26%) went to El Niño. (16 went to neutral and 18 remained La Niña). Of the 12 La Ninas with an April NYC snowstorm, 6 (50% or ~twice the overall %) went to El Niño. That means that of the 34 La Ninas without a snowstorm, only 6 (18%) went to El Niño (just over 1/3 the rate of La Niñas with a snowstorm going to El Niño). So, perhaps having a La Niña April NYC snowstorm is indicative of a higher than the normal small chance for El Niño to follow La Niña.

[GaWx]

On 2/22/2025 at 12:23 PM, GaWx said:

And GEFS still had no signal for a major SSW as of yest:

Here’s the next day’s 0Z extended GEFS update (2/22/25 run, which is latest til tonight) with a much weaker mean SPV per 60N mean zonal winds at 10 mb due to a doubling from 6 members (out of 30 or 20%) with a major SSW 3/9-16 to 12 members (40%). The prior run’s (2/21/25 run) mean dipped only down to +20 on 3/15. This most recent run’s mean dips down to +4:

[Maxim]

Lol we still doing this SSW stuff huh

[GaWx]

37 minutes ago, Maxim said:

Lol we still doing this SSW stuff huh

 Range for major SSWs since 1958: Nov 28th (in 1968) to Mar 24th (2010). Six of the 44 in the list below occurred anywhere from around the time this one would possibly occur to 3/24. The very late ones had no effect on met. winter obviously since it had already ended. However, the Mar ones can cool a portion of early to mid met spring in the E US. They usually do that 2+ weeks later. A chilly spring doesn’t necessarily mean a snowstorm. There are many aspects of wx forecasting that have nothing to do with snow or extreme cold.

https://en.m.wikipedia.org/wiki/Sudden_stratospheric_warming

[snowman19]

30 minutes ago, GaWx said:

 Range for major SSWs since 1958: Nov 28th (in 1968) to Mar 24th (2010). Six of the 44 in the list below occurred anywhere from around the time this one would possibly occur to 3/24. The very late ones had no effect on met. winter obviously since it had already ended. However, the Mar ones can cool a portion of early to mid met spring in the E US. They usually do that 2+ weeks later. A chilly spring doesn’t necessarily mean a snowstorm. There are many aspects of wx forecasting that have nothing to do with snow.

https://en.m.wikipedia.org/wiki/Sudden_stratospheric_warming

I mean at this point, wouldn’t a SSWE in mid-late March basically just be masquerading as a yearly final warming?  Spring solar radiation induced final warmings typically occur between mid-late March or in April, give or take anyway…..

[GaWx]

2 hours ago, snowman19 said:

I mean at this point, wouldn’t a SSWE in mid-late March basically just be masquerading as a yearly final warming?  Spring solar radiation induced final warmings typically occur between mid-late March or in April give or take anyway…..

 Thanks for bringing this up!

 The average date of the final warming is not for a full month after this potential SSW. It is on Apr 12. The average is actually later when there is a very late wind reversal that isn’t a FW. I’ll now look at the years with the 6 latest major SSWs and compare to the final warmings per the chart below. (I’ve never done this. So, this will be interesting):

https://wcd.copernicus.org/articles/2/453/2021/#:~:text=Every spring%2C the stratospheric polar vortex transitions,known as the “final stratospheric warming” (FSW).&text=In the NH%2C the median date of,hPa and 15 April at 50 hPa.
 

1. 1965: SSW 3/25; FW 4/19

2. 1969: SSW 3/13; FW 4/13

3. 1971: SSW 3/20; FW 4/24

4. 1988: SSW 3/14; FW 4/6

5. 2000: SSW 3/20; FW 4/9

6. 2010: SSW 3/24; FW 4/30

 So, after each of these 6 very late SSWs/wind reversals, the mean 60N 10 mb wind unreversed for a period til the final warming. For example:

-2010’s very late reversal ended ~3/26, which was 5 weeks before its 4/30 FW:

 

-2000’s very late reversal ended ~3/22, which was 2.5 weeks before it’s 4/9 FW:

 The other 4 very late reversals all ended ~3-4 weeks prior to the respective FW.

 So the answer to your good question is “no”.

[Maxim]

1 hour ago, GaWx said:

 Range for major SSWs since 1958: Nov 28th (in 1968) to Mar 24th (2010). Six of the 44 in the list below occurred anywhere from around the time this one would possibly occur to 3/24. The very late ones had no effect on met. winter obviously since it had already ended. However, the Mar ones can cool a portion of early to mid met spring in the E US. They usually do that 2+ weeks later. A chilly spring doesn’t necessarily mean a snowstorm. There are many aspects of wx forecasting that have nothing to do with snow or extreme cold.

https://en.m.wikipedia.org/wiki/Sudden_stratospheric_warming

I’ll believe it when I see it

[Daniel Boone]

34 minutes ago, GaWx said:

 Thanks for bringing this up!

 The average date of the final warming is not for a full month after this potential SSW. It is on Apr 12. The average is actually later when there is a very late wind reversal. I’ll now look at the years with the 6 latest major SSWs and compare to the final warnings per the chart below. (I’ve never done this. So, this will be interesting):

https://wcd.copernicus.org/articles/2/453/2021/#:~:text=Every spring%2C the stratospheric polar vortex transitions,known as the “final stratospheric warming” (FSW).&text=In the NH%2C the median date of,hPa and 15 April at 50 hPa.
 

1. 1965: SSW 3/25; FW 4/19

2. 1969: SSW 3/13; FW 4/13

3. 1971: SSW 3/20; FW 4/24

4. 1988: SSW 3/14; FW 4/6

5. 2000: SSW 3/20; FW 4/9

6. 2010: SSW 3/24; FW 4/30

 So, after each of these 6 very late SSWs/wind reversals, the mean 60N 10 mb wind unreversed for a period til the final warming. For example:

-2010’s very late reversal ended ~3/26, which was 5 weeks before its 4/30 FW:

 

-2000’s very late reversal ended ~3/22, which was 2.5 weeks before it’s 4/9 FW:

 The other 4 very late reversals all ended ~3-4 weeks prior to the respective FW.

 So the answer to your good question is “no”.

Thanks for all the excellent work you do Larry. You're the best man !

[GaWx]

2 hours ago, snowman19 said:

I mean at this point, wouldn’t a SSWE in mid-late March basically just be masquerading as a yearly final warming?  Spring solar radiation induced final warmings typically occur between mid-late March or in April, give or take anyway…..

I should add that if there is a reversal in mid March, I’m not saying it couldn’t end up being a FW since several FWs have occurred that early per what you said and the FW table I just posted. ~1 in 12 FWs since 1958 have occurred by Mar 13th. Some of the ensemble members appear to be FWs as they don’t come back up to the 0 line. We’ll no more as get closer to the possible wind reversal and the ensemble members start converging. Right now they’re all over the place.

[GaWx]

 Today’s Euro Weeklies suggest that (wind reversal or not in mid March) that the winter is nearly over. What I mean by that is no week-long period of BN temps for most of the E US. Other than New England being NN 3/3-9, the rest of the weeks are dominated by AN temp signals outside of FL the first 3 weeks.