2024-2025 La Nina

[GaWx]

1 minute ago, Stormchaserchuck1 said:

Jan-Feb-March is where the heaviest correlation hits. But this based on the whole dataset, 1948-2023, 75 years, not just 6 years. You can research it for yourself on the CPC NAO data. I think we talked about this last year. 

I find it interesting, because no other month of the year has a <50% correlation, then all of a sudden October is 45%. When you have 76 years of data, that tells me the signal is at least neutral, not positive.. of course over like 200 years it may be closer to 50%. 

Thanks. I like to just look at 1979-80+ because we’re in a winter +NAO era that started them. I’m still trying to figure out why.

 I prefer to look at DJF since it’s net winter but I’ll look at JFM since 1979-80.

Changes in NAO status when changing to JFM:

Additions: 1980, 2013

Deletions: 2011, 2021

 

Additions:

 -1980: prior Oct had -0.3

 -2013: prior Oct had -2.1

 

Deletions:

-2011: prior Oct had -0.9

-2021: prior Oct had -0.7

—————————

So, net change for last 45 years was essentially a wash JFM vs DJF

So, still 1/4 (or 1/3 if keeping neutrals)

 

[GaWx]

55 minutes ago, Stormchaserchuck1 said:

Use the whole dataset.. + and - events for JFM vs October. Try it out for amplitude >0.50 and >1.00 events in October. On this site below, it does the whole thing as a correlation composite for you. (Before I found out about that, I had calculated it manually in the past, and came up with the same results.)

https://psl.noaa.gov/data/correlation/

Dec is 50-51% 

The highest reverse correlation is March.

CPC NAO: https://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/norm.nao.monthly.b5001.current.ascii.table

What you will find is that both positive, and negative NAO phases reverse in JFM, and even if you do DJFM for the Winter as a whole

Chuck, I did a quick and dirty check of 1950-1979 for Oct NAO >+0.5. I did see a large portion of those become -NAO JFM. But here’s my concern about this:

- Oct NAO >+0.5 much more common 1950-79 (15 of 30 or 50%) vs 1980-2023 (only 5 of 44 or a mere 11%)

- JFM NAO <-0.25 much more common 1951-1979 (17 of 29 or 59%) vs 1980-2024 (only 6 of 45 or 13%)

 So, of course there is a significantly higher % of +NAO Octs that switch sign for JFM in 1951-79 (a whopping 10 of 15 or 67%) vs in 1980-2024 (only 1 of 5 or 20%). They’re like two different eras to me and thus I like to stick to the current +NAO winter era of last 45 years.

 

[Stormchaserchuck1]

24 minutes ago, GaWx said:

Chuck, I did a quick and dirty check of 1950-1979 for Oct NAO >+0.5. I did see a large portion of those become -NAO JFM. But here’s my concern about this:

- Oct NAO >+0.5 much more common 1950-79 (15 of 30 or 50%) vs 1980-2023 (only 5 of 44 or a mere 11%)

- JFM NAO <-0.25 much more common 1951-1979 (17 of 29 or 59%) vs 1980-2024 (only 6 of 45 or 13%)

 So, of course there is a significantly higher % of +NAO Octs that switch sign for JFM in 1951-79 (a whopping 10 of 15 or 67%) vs in 1980-2024 (only 1 of 5 or 20%). They’re like two different eras to me and thus I like to stick to the current +NAO winter era of last 45 years.

They might not be unrelated though.  I made a prediction in this thread a while back that when the Fall pattern started (late Sept into Oct), we would probably see a -NAO and -PNA. This has been the way it has progressed over the years, over and over again. It might be something in the overall global pattern that causes Oct and the Winter NAO to be opposite. 

I just know that when you have both signs of an index showing the same thing (seems like you did it for +October's.. it works for -October's too), it should have some level of credence. 

Edit: I would be interested to know if it works the same recently. My thoughts are it still has a -correlation, but not as strong as before. We have seen a good amount of -NAO Oct's lately, and we know that Winter's have been mostly +NAO per CPC calculations..  Now doing a quick research, The last 5 years have all been -NAO Octobers. 5 +NAO Winter's. From '01-14 we had 12/14 -NAO October's.. and you say that the Winter NAO has only been negative 4 times since 1979? Seems to work imo. 

[GaWx]

For the first time in a very long time, 3.4 per OISST, CRW, CDAS; OHC, and TAO buoys are all at their coolest of the year to date.

[so_whats_happening]

Ok now lets just translate this to 3 months from now... lol

It still does amaze me we can get better patterns in the off seasons then when winter hits it is like brick wall of nope.

 

[so_whats_happening]

Some rather significant weakening in the VP anomalies around the Maritime coming up on just about every model. This may be a rather brief but exceptional opening of the Atlantic/ Caribbean to tropical activity closing out the month into October.

Pretty decent cooling of waters to now just slightly above average around Malaysia (I think that is the country 120E, ~15N).

This is also the most impressive the Nina has looked thus far.

[Stormchaserchuck1]

2 minutes ago, so_whats_happening said:

This is also the most impressive the Nina has looked thus far.

That N. Pacific warm pool is so strong, and the La Nina is turning west-based!  I wouldn't be surprised if Sept has a PDO <-3 after seeing that. 

[GaWx]

16 minutes ago, so_whats_happening said:

Some rather significant weakening in the VP anomalies around the Maritime coming up on just about every model. This may be a rather brief but exceptional opening of the Atlantic/ Caribbean to tropical activity closing out the month into October.

Pretty decent cooling of waters to now just slightly above average around Malaysia (I think that is the country 120E, ~15N).

This is also the most impressive the Nina has looked thus far.

What do you know about the cause of that insanely warm N Pacific area? It wouldn’t surprise me if some anomalies in that +5+ area are +8+! 
 I’ve been reading about underwater seismic activity possibly being a cause. What do you know about that?

[so_whats_happening]

3 minutes ago, GaWx said:

What do you know about the cause of that insanely warm N Pacific area? It wouldn’t surprise me if some anomalies in that +5+ area are +8+! 
 I’ve been reading about underwater seismic activity possibly being a cause. What do you know about that?

It is a possibility for maybe having the extreme anomaly presence, as far we know the NW Atlantic does not have major seismic activity. So when the Atlantic and Pacific have mirror looks it makes me have pause that could be the situation. The NW Atlantic has a more shallow depth region so that may play a role in having a mirror look to the Pacific without the Seismic influence.

Honestly though it is a mystery as of now why the pattern is pushing extremes and what exactly it will take to rid us of this pattern. The tropical activity early on put dents into it here and there but has since smoothed out the area just NE of Japan I am curious about the storm track this year and how much change will occur over winter.

[so_whats_happening]

31 minutes ago, so_whats_happening said:

 

I wanted to add the end of summer comparison to last year I have in stock. This new one starts on 9/6 to 12/4. The warm anomalies are east of where they were at the start of September last year so we are seeing a shift occur not as intense around Japan but still very warm in many regions around Japan.

[so_whats_happening]

Just now, so_whats_happening said:

I wanted to add the end of summer comparison to last year I have in stock. This new one starts on 9/6 to 12/4. The warm anomalies are east of where they were at the start of September last year so we are seeing a shift occur not as intense around Japan but still very warm in many regions around Japan.

It was around the end of September when we saw the 500mb pattern take hold and SST configurations sort of lock in. It will be interesting to see what the next 3 weeks looks like.

[Stormchaserchuck1]

6 minutes ago, so_whats_happening said:

It was around the end of September when we saw the 500mb pattern take hold and SST configurations sort of lock in. It will be interesting to see what the next 3 weeks looks like.

Trying to build that Aleutian ridge on LR models.. look at how it extends back to Japan. 

[so_whats_happening]

46 minutes ago, Stormchaserchuck1 said:

That N. Pacific warm pool is so strong, and the La Nina is turning west-based!  I wouldn't be surprised if Sept has a PDO <-3 after seeing that. 

Yea it is possible, if this would happen it would surpass 2011 and start to rival the one month anomaly of Oct 1955 where we got to -3.35. Fairly similar placement as for the most extreme SST anoms.

4 minutes ago, Stormchaserchuck1 said:

Trying to build that Aleutian ridge on LR models.. look at how it extends back to Japan. 

How have the models faired so far in extended forecasts? Just curious this is not something I follow all too often.

[Stormchaserchuck1]

4 minutes ago, so_whats_happening said:

How have the models faired so far in extended forecasts? Just curious this is not something I follow all too often.

They have about a 0.80 correlation.. the accuracy has improved over the years.  That the ridge is over such a large area in the N. Pacific on the mean adds some validity. 

[Stormchaserchuck1]

Just some random thoughts.. but I have seen when something goes so extreme, something may attempt to "even it out" in the shorter term. 

Here is Dec-Jan 55-56 (after most -PDO month on record, Oct 1955, as so-what's-happening pointed out)

In December 2021, the -PNA was so strong.. going >+600dm for several days, that in January it reversed with a +PNA, despite a La Nina. Then in January in following years we saw -PNA conditions

The Winter after 55-56:

 

Side note, but Phoenix has broken it's record of most 100+ degree days by 37 days! 

Here is what those "new data points" look like in December-January (for >38 as a baseline)

I could be completely wrong, and the PDO may just have it's usual correlation from this point on.. but it will be interesting to see if the atmosphere swings, re: something so new and extreme (and some data points to Dec-Jan). I've just noticed this happening a lot from 2021-2024. Made a thread about it a long time ago, and predicted some +1 year periods correctly, based on the opposite of an extreme monthly value the year before. 

I agree that it will be interesting to see the Fall and Winter progress

I think if heavy -PNA isn't hit this Winter, it will hit next Winter. 

[so_whats_happening]

5 minutes ago, Stormchaserchuck1 said:

Just some random thoughts.. but I have seen when something goes so extreme, something will attempt to "even it out" in the short term. 

Here is Dec-Jan 55-56 (after most -PDO month on record, Oct 1955, as so-what's-happening pointed out)

In December 2021, the -PNA was so strong.. going >+600dm for several days, that in January it "evened out" with a +PNA. Then in January in following years we saw -PNA conditions

The Winter after 56-57:

 

Phoenix has broken it's record of most 100+ degree days by 37 days! 

Here is what those "new data points" look like in December (for >38 as a baseline)

I could be completely wrong, and the PDO may just have it's usually correlation from this point on.. but it will be interesting to see if something does make some attempt to "even it out" (and some data points to Dec-Jan). I've just noticed this happening a lot from 2021-2024, that's all. Made a thread about it a long time ago, and predicted some +1 year periods correctly, based on the opposite of an extreme monthly value the year before. 

 

The lowest monthly ever recorded was actually April of 1859 and July of 1950 where we bottomed out at -3.65 for a monthly value but at that point we are looking rather far into the past and the symmetry of pattern evolution may not be there.

My guess for this year is we get the continuum of central plains/ front range cold dumps. With having a SE Ridge pop up from time to time but as of now nothing in the extreme department from my perspective. Definitely feels like a relaxation for this intense east coast warmth during winter but still averaging above average for the season overall (just not +6 maybe more like +1 to+2). Ill gladly take something else for a change but persistence has been great so far this year, so far last month and so far September have been the only bigger anomalies this year for temps in the east.

[Stormchaserchuck1]

8 minutes ago, so_whats_happening said:

The lowest monthly ever recorded was actually April of 1859 and July of 1950 where we bottomed out at -3.65 for a monthly value but at that point we are looking rather far into the past and the symmetry of pattern evolution may not be there.

My guess for this year is we get the continuum of central plains/ front range cold dumps. With having a SE Ridge pop up from time to time but as of now nothing in the extreme department from my perspective. Definitely feels like a relaxation for this intense east coast warmth during winter but still averaging above average for the season overall (just not +6 maybe more like +1 to+2). Ill gladly take something else for a change but persistence has been great so far this year, so far last month and so far September have been the only bigger anomalies this year for temps in the east.

Yeah.. we are progressing well with decadal trends this year so far.. it's actually been very similar. Now this N. American ridge, -NAO, and -PNA in late Sept/Oct is even more confirmation that we are on course with the last few years. It's hard to predict below average anywhere these days, but I think a strong -PNA for the Winter may actually take some time to build. We may see some chaos as it starts this Winter, especially early on (a lot points to RNA Feb as the decadal trend here is +120dm Aleutian ridge as the mean for Feb-Mar since 2018). I wouldn't say expect a colder than normal Dec-Jan, but watch for maybe some pattern breaks during this time.. 

[so_whats_happening]

1 minute ago, Stormchaserchuck1 said:

Yeah.. we are progressing well with decadal trends this year so far.. it's actually been very similar. Now this N. American ridge, -NAO, and -PNA in late Sept/Oct is even more confirmation that we are on course with the last few years. It's hard to predict below average anywhere these days, but I think a strong -PNA for the Winter may actually take some time to build. We may see some chaos as it starts to try this Winter, especially early on (a lot points to -PNA Feb as the decadal trend here is +120dm Aleutian ridge as the mean for Feb-Mar since 2018. 

This is the first time in about 6 years we have had a +NAO summer. Most have been neutral for a month and mostly negative overall. The last time we had a positive NAO summer was 2017 and 2018 and before that 2013. Folks draw whatever they want from that sample set but notably 2013 was the only other one in the last 15 or so years that has had high solar as well as a +QBO pattern to boot. 

Im sure ill get the usual commentary of the SST patterns were entirely different. I get it not everything will be perfect as much as I would love it to be (would make things a hell of a lot easier).

[Stormchaserchuck1]

7 minutes ago, so_whats_happening said:

This is the first time in about 6 years we have had a +NAO summer. Most have been neutral for a month and mostly negative overall. The last time we had a positive NAO summer was 2017 and 2018 and before that 2013. Folks draw whatever they want from that sample set but notably 2013 was the only other one in the last 15 or so years that has had high solar as well as a +QBO pattern to boot. 

Im sure ill get the usual commentary of the SST patterns were entirely different. I get it not everything will be perfect as much as I would love it to be (would make things a hell of a lot easier).

We are kind of due for a -WPO/-EPO Winter, 5 of the last 6 Winter's have been positive, and the one year that was not was Neutral. The WPO doesn't have much to do with the PDO in the Winter months

Maybe more negative phases of those indexes has something to do with +NAO? I've certainly observed this Pacific-Atlantic correlation since 2013, and it actually goes all the way back to 2007. 

[so_whats_happening]

On 5/18/2024 at 4:15 PM, so_whats_happening said:

Again sorry for all the posts but one final one. If we combined all the years mentioned above we get not a bad look to what may be to come. Maybe warm it by about a degree?

Honestly I still like this look for an overall guess to the winter. I would expect the warmth in the south to be a bit more bulbous with an episode or two of SE Ridge flaring up and a dislodged -NAO. Again as much as I would like a pure -NAO winter season it doesn't seem very likely.

Temps would likely be about 1-2C warmer but the general idea is there.

[bluewave]

This was actually the strongest +AO +NAO summer since 2018.

 

[40/70 Benchmark]

15 hours ago, mitchnick said:

+NAO for October on the Cfs2, if true, bodes well for winter chances of a -NAO per Chuck's historical odds.

It also has the nascent PV really tiled se towards NE...I have noticed a lot of guidance doing that during the winter, as well. CANSIPS does it, too. Good way to run a decent winter regardless of NAO. Good way to get an active gradient pattern.

[40/70 Benchmark]

10 hours ago, so_whats_happening said:

The lowest monthly ever recorded was actually April of 1859 and July of 1950 where we bottomed out at -3.65 for a monthly value but at that point we are looking rather far into the past and the symmetry of pattern evolution may not be there.

My guess for this year is we get the continuum of central plains/ front range cold dumps. With having a SE Ridge pop up from time to time but as of now nothing in the extreme department from my perspective. Definitely feels like a relaxation for this intense east coast warmth during winter but still averaging above average for the season overall (just not +6 maybe more like +1 to+2). Ill gladly take something else for a change but persistence has been great so far this year, so far last month and so far September have been the only bigger anomalies this year for temps in the east.

 

10 hours ago, Stormchaserchuck1 said:

Yeah.. we are progressing well with decadal trends this year so far.. it's actually been very similar. Now this N. American ridge, -NAO, and -PNA in late Sept/Oct is even more confirmation that we are on course with the last few years. It's hard to predict below average anywhere these days, but I think a strong -PNA for the Winter may actually take some time to build. We may see some chaos as it starts this Winter, especially early on (a lot points to RNA Feb as the decadal trend here is +120dm Aleutian ridge as the mean for Feb-Mar since 2018). I wouldn't say expect a colder than normal Dec-Jan, but watch for maybe some pattern breaks during this time.. 

Yea, same page....I see something qualitatively similar to the past several years, but not so prohibitive.

[bluewave]

11 hours ago, GaWx said:

What do you know about the cause of that insanely warm N Pacific area? It wouldn’t surprise me if some anomalies in that +5+ area are +8+! 
 I’ve been reading about underwater seismic activity possibly being a cause. What do you know about that?

The warmer SSTs are the result of the record 500mb ridge east of Japan with light winds and more sunshine allowing the SSTs below to warm. 
 

[snowman19]

Another possible correlation between high geomag and the Atlantic hurricane season:

[snowman19]

12 hours ago, Stormchaserchuck1 said:

That N. Pacific warm pool is so strong, and the La Nina is turning west-based!  I wouldn't be surprised if Sept has a PDO <-3 after seeing that. 

With this look, my guess is that this month averages close a -3 PDO

[PhiEaglesfan712]

1955-56 was a strong ONI la nina. Winter wasn't too cold (especially January and February), but November and December were cold, as were the spring months.

1956-57 was pretty much a weaker version la nina of 2022-23, a 3rd year la nina that dissipated early in the season. I'm not surprise the map was warm and resembled 2022-23.

The big difference is that the subsurface was warm throughout. I'm pretty sure if this board was around that time, they'd be calling for an el nino in 1955-56 or 1956-57.

Maybe we're heading into a 1954-57 pattern, where we get a multi-year la nina that reaches its peak intensity in Year 2, rather than Year 1.

[michsnowfreak]

13 hours ago, Stormchaserchuck1 said:

Trying to build that Aleutian ridge on LR models.. look at how it extends back to Japan. 

Doesn't the aleutian ridge bring troughing to the east half of the country?

[bluewave]

39 minutes ago, michsnowfreak said:

Doesn't the aleutian ridge bring troughing to the east half of the country?

If Aleutian Ridge results in a -PNA with trough axis potentially from the West Coast to Upper Plains then it pumps the Southeast Ridge. We want the Aleutian Ridge with a +PNA like January 22 and ridging building into the Rockies. But most of the time in recent years we had -PNA Aleutian Ridge amplifications which pumped the Southeast Ridge.

 

[PhiEaglesfan712]

14 hours ago, GaWx said:

What do you know about the cause of that insanely warm N Pacific area? It wouldn’t surprise me if some anomalies in that +5+ area are +8+! 
 I’ve been reading about underwater seismic activity possibly being a cause. What do you know about that?

If that's the case, then I guess the 2011 Tōhoku earthquake may be the culprit. We've been in a perpetual warm blob in the North Pacific since 2013-14.