2024-2025 La Nina

[Stormchaserchuck1]

La Nina is coming in real nicely on CDC daily composites.  Starting east-based like the last few we've had since 2000. 

https://freeimage.host/i/JLxCQov

[Stormchaserchuck1]

12 hours ago, GaWx said:

 The WCS PDO for May is headed for ~-1.8. Based on the avg ratio between the PDO of WCS and NOAA, I’m projecting the NOAA May PDO will come out to ~-2.7 (-2.5 to -2.9), easily the lowest in May since 1950. Even a -2.45 would be the lowest May since 1950:

Yeah, crazy -PDO right now. Some of the SST maps were showing +5c anomalies south of the Aleutian islands.  The PDO correlated with the weather pattern more than ENSO in this past Winter, and the historical correlation composites actually shows that this is the case most of the time! (There are just a few months where ENSO correlates greater, even though I think the ENSO effect has been strong for the last 70 years). The Earth is "tranquil" right now, so I think that stuff is probably amplified.

Good signal for Summer heat in New England.. +0.3 is pretty strong for a 3-month average, going back to 1948. 

https://ibb.co/4YjNgPg

^I think the CPC currently has a similar temperature map as their Summer forecast. (Remember, the map I posted above the correlation is opposite)

October is a really strong map for temperature correlation. https://ibb.co/4fLngZK

[Stormchaserchuck1]

8 hours ago, GaWx said:

 - Thus with almost certain La Niña upcoming, -PDO this winter very likely

Stronger La Nina, record -PDO, record +AMO, Solar max, and probable +QBO (+QBO/La Nina combo favors strong 10mb vortex and +AO), this definitely looks like a warmer Winter, but it was in the 40s in May so you never know.. sometimes La Nina patterns can be blocky. 

[GaWx]

5 minutes ago, Stormchaserchuck1 said:

Stronger La Nina, record -PDO, record +AMO, Solar max, and probable +QBO (+QBO/La Nina combo favors strong 10mb vortex and +AO), this definitely looks like a warmer Winter, but it was in the 40s in May so you never know.. 

Chuck,

1. The record NOAA -PDO is -2.61 (1948-9). (Interestingly, that winter was neutral ENSO rather than La Niña.) This month has been near that avg. But I think it will still be a big challenge for the upcoming winter to avg near that strong even with the help of La Niña since 1948-9 was so phenomenally strong. The next strongest is -2.34 (2021-2)(moderate La Niña), 3rd strongest is -2.25 (1955-6)(strong La Niña, and 4th is -2.09 (1872-3)(weak La Niña). So, four sub -2 PDO winters over the last 170 years or one every 42.5 winters on avg.

 Could we get the 5th sub -2 PDO this winter? Yes, but the odds would be higher for -1.5 to -2.0 based on the data showing 16 winters in that range (4 times the frequency of sub -2) or ~one every 11 winters. That’s my educated guess as of now. We’ll see!

2. When you say “warmer winter”, do you mean warmer than last winter or just warmer than normal?

[Stormchaserchuck1]

23 minutes ago, GaWx said:

2. When you say “warmer winter”, do you mean warmer than last winter or just warmer than normal?

I think recent trends favor warmer than normal, since 85% of our months are ending up this way now on average. And we are having peaks, where we hit 80 in DC on Jan 26th, which was the first time ever for I think 12-1 to 2-28 (the coldest day of the year on average is Jan 27th).  I am no way getting the super warm Winter vibe though, part of that is the N. Atlantic SST index that I monitor for the following Winter's NAO is slightly negative, and it's been a temperate Spring, which went against the SE ridge trend that I thought would prevail. Arctic ice is also all the way down to 14th lowest.  I also found the SW, US leads us a lot of the time, and when they were getting anomalous High pressure all the time 1995-2020, that boded bad for future Winter's, but the last 2 years troughs have really dug deep into the SW, which has broken that trend a little bit. 

[Stormchaserchuck1]

Another matter of concern is if the strong -PDO pattern does set up for Hurricane season, it could favor a pattern that supports GOM and FL hits, as storms track under the mean ridge in the northern latitudes. 

https://ibb.co/QvQ5rzm

For east coast hits, you want that ridge further east over New Foundland and SE Canada. 

[snowman19]

8 hours ago, Stormchaserchuck1 said:

La Nina is coming in real nicely on CDC daily composites.  Starting east-based like the last few we've had since 2000. 

https://freeimage.host/i/JLxCQov

The models are showing it starting east-based, then quickly transitioning to central-based/Modoki by November, late fall. No reason to doubt that evolution right now

[PhiEaglesfan712]

5 hours ago, Stormchaserchuck1 said:

I think recent trends favor warmer than normal, since 85% of our months are ending up this way now on average. And we are having peaks, where we hit 80 in DC on Jan 26th, which was the first time ever for I think 12-1 to 2-28 (the coldest day of the year on average is Jan 27th).  I am no way getting the super warm Winter vibe though, part of that is the N. Atlantic SST index that I monitor for the following Winter's NAO is slightly negative, and it's been a temperate Spring, which went against the SE ridge trend that I thought would prevail. Arctic ice is also all the way down to 14th lowest.  I also found the SW, US leads us a lot of the time, and when they were getting anomalous High pressure all the time 1995-2020, that boded bad for future Winter's, but the last 2 years troughs have really dug deep into the SW, which has broken that trend a little bit. 

I get the feeling 2024-25 is going to be a below average temperature winter. We are just well overdue for one. The last one that came below normal was at PHL was in 2014-15, which is going to be ten years ago. We came close in 2017-18 (the first half of that winter was very cold), but February was well above average, pushing that winter to an above average temperature finish.

[snowman19]

9 hours ago, Stormchaserchuck1 said:

Stronger La Nina, record -PDO, record +AMO, Solar max, and probable +QBO (+QBO/La Nina combo favors strong 10mb vortex and +AO), this definitely looks like a warmer Winter, but it was in the 40s in May so you never know.. sometimes La Nina patterns can be blocky. 

When you add in the effects from a possible volcanic stratosphere (1st winter after the eruptions), the signal for a +AO grows even more

[40/70 Benchmark]

1 hour ago, snowman19 said:

When you add in the effects from a possible volcanic stratosphere (1st winter after the eruptions), the signal for a +AO grows even more

Not necessarily....not all volcanic eruptions are created equal...depends on where it was, how strong, what was emitted, etc..

[roardog]

44 minutes ago, 40/70 Benchmark said:

Not necessarily....not all volcanic eruptions are created equal...depends on where it was, how strong, what was emitted, etc..

How long does it usually take to get all of that information? I haven’t even seen an official VEI rating yet.

[snowman19]

40 minutes ago, roardog said:

How long does it usually take to get all of that information? I haven’t even seen an official VEI rating yet.

@Volcanic Winter

[40/70 Benchmark]

On 5/26/2024 at 12:48 PM, snowman19 said:

@Volcanic Winter

That said, clearly I agree a strong PV is favored...just not sure how large of a factor any eruptions will be.

[raindancewx]

The big heat wave over Mexico seems tied to a big high (at 500 mb) centered at like 21N / 95W. I think that's probably going to suppress hurricane activity away from the US Southeast for a while until something comes in to kill it. My guess is it will be destroyed from the West by the East Pacific hurricane season eventually - not sure though.

The dome of heat in May 1998 was centered somewhat north and weaker. Huge area of +7F or hotter centered around 20N/98W

[Stormchaserchuck1]

That old Mexico heat wave is really interesting. I thought the SE ridge would flex in the Spring, as things seemed to be trending drier in the Winter, we were having a lot of cloudless days. It's been the opposite, wet and cool. But the Hadley Cell expansion energy appears to still be there, just little further south.  I think at some point it will flex over the CONUS. 

Any other analysis you have of the heat wave there? 

[Stormchaserchuck1]

For the Mexican heat wave Since 1998, I have +2022, +2003, +1998, -2014. Here's peak warm season: https://ibb.co/Qf22K0Y

(Going forward more: https://ibb.co/g47XqgR)

[snowman19]

1 hour ago, 40/70 Benchmark said:

That said, clearly I agree a strong PV is favored...just not sure how large of a factor any eruptions will be.

Stratospheric effects TBD, but Volcanic Winter said the cumulative effects all added up should definitely come to a VEI 5. They appeared to be classic tropical eruptions which injected sulfate aerosols into the stratosphere, as opposed to an atypical one like Hunga Tonga, which was almost all water vapor

[40/70 Benchmark]

9 hours ago, snowman19 said:

Stratospheric effects TBD, but Volcanic Winter said the cumulative effects all added up should definitely come to a VEI 5. They appeared to be classic tropical eruptions which injected sulfate aerosols into the stratosphere, as opposed to an atypical one like Hunga Tonga, which was almost all water vapor

Cool. May as well get it out of the way this year when we are screwed, regardless.

[40/70 Benchmark]

9 hours ago, Stormchaserchuck1 said:

For the Mexican heat wave Since 1998, I have +2022, +2003, +1998, -2014. Here's peak warm season: https://ibb.co/Qf22K0Y

(Going forward more: https://ibb.co/g47XqgR)

2022 and 1998 are on my early list.

[snowman19]

1 hour ago, 40/70 Benchmark said:

2022 and 1998 are on my early list.

The more I look at it, the more they do look like decent analogs so far

[GaWx]

1. Latest (5/25/24) BoM model run sticking with only down to -0.07 for lowest ONI (not RONI) in autumn (SON):

 

But keep in mind that it had a large warm bias last year. Its 5/20/23 run had SON ONI way up at +2.53 or 0.75 warmer than +1.78 actual:

 

 The next BoM run (6/3/23) had SON ONI even warmer (+2.73), which verified 0.95 too warm!

 

2. In stark contrast, the UKMET May of 2024 run has ASO ONI way down at -1.01 (though that’s actually significantly warmer than its prior run for JAS of -1.28):

But unlike the way too warm BoM, the May of 2023 UKMET run for ASO ONI was nearly spot on with its +1.84 prog, a mere 0.06 too warm:

3. So, between the latest BoM and UK, I heavily favor the latest UK to end up the closer of the two for this fall’s ONI. Not necessarily nearly spot on but at least closer. And keep in mind that RONI would undoubtedly be significantly cooler than ONI.

[snowman19]

20 minutes ago, GaWx said:

1. Latest (5/25/24) BoM model run sticking with only down to -0.07 for lowest ONI (not RONI) in autumn (SON):

 

But keep in mind that it had a large warm bias last year. Its 5/20/23 run had SON ONI way up at +2.53 or 0.75 warmer than +1.78 actual:

 

 The next BoM run (6/3/23) had SON ONI even warmer (+2.73), which verified 0.95 too warm!

 

2. In stark contrast, the UKMET May of 2024 run has ASO ONI way down at -1.01:

But unlike the way too warm BoM, the May of 2023 UKMET run for ASO ONI was nearly spot on with its +1.84 prog, a mere 0.06 too warm:

 So, between the latest BoM and UK, I heavily favor the latest UK to end up the closer of the two for this fall’s ONI. Not necessarily nearly spot on but at least closer. And keep in mind that RONI would undoubtedly be significantly cooler than ONI.

The BOM’s consistent severe warm bias last year, run after run for months was simply astonishing 

[snowman19]

[Stormchaserchuck1]

Models have a pretty good +AAM pattern starting early June. this may keep the La Nina peak near Moderate strength vs Strong. raindancewx has posted that we have a tendency to warm La Nina events since ~2000-05. The overall global warming trend may make it harder to see Strong La Nina events in the future, per the ONI. 

I still think the La Nina-base state that we have seen since 2000 is pretty incredible. This means that we are seeing La Nina patterns generally, even when it's not a La Nina. Some are quick to blame it on the PDO, but water is more reactive than proactive imo.   Southern Hemisphere version of the PNA has also been pretty on par with the N. Hemisphere during that time, which means that forcing might be coming from the equator.  

[Typhoon Tip]

1 hour ago, Stormchaserchuck1 said:

Models have a pretty good +AAM pattern starting early June. this may keep the La Nina peak near Moderate strength vs Strong. raindancewx has posted that we have a tendency to warm La Nina events since ~2000-05. The overall global warming trend may make it harder to see Strong La Nina events in the future, per the ONI. 

I still think the La Nina-base state that we have seen since 2000 is pretty incredible. This means that we are seeing La Nina patterns generally, even when it's not a La Nina. Some are quick to blame it on the PDO, but water is more reactive than proactive imo.   Southern Hemisphere version of the PNA has also been pretty on par with the N. Hemisphere during that time, which means that forcing might be coming from the equator.  

Strange ... the GLAAM outlook from the CF model cluster would indeed suggest mid latitude expansion of subtropical ridging ... (really an polaward HC boundary migration) while the numerical teleconnectors (based off the global numerical ensemble systems, all 3, are going bonkers with this +PNA) 

- that attempts to deny the +AAM.  +AAM modulates away from meridian flow transports in lieu of longitudinal, yet this...  And it's more than this just transiently passing through this construct around that time interval ... the ensemble means set this up D8 and run it out to the annular finish at D15 still harboring a hint of the OV nadir there.   Bit of a diametric indication going on.

 

[Stormchaserchuck1]

12 hours ago, 40/70 Benchmark said:

2022 and 1998 are on my early list.

Cool.. I'm glad you're into long range forecasting. 

I've noticed a Hadley Cell expansion over the last few years, and in my opinion more stable factors have higher weight right now, but we do create a dichotomy for some extreme events to even it out at some point in future time (years to decades). https://ibb.co/KLdH8ZL Therefore, I think some form of consistency could be a more effective way to go right now (-PDO is in its 26th year and +AMO is in its 29th year, and they are both still deepening!). 

[raindancewx]

Last year had a big heat wave in Mexico too. But it was in June, which is rare overall, but more common in the stronger El Ninos.

Global SSTs have 30-32C temps by Mexico and the Philippines right now. That's why I was thinking a couple big hurricanes may end that big high - the fuel is there if something can develop.

If we get the effects of the Tonga eruption to decay while the aerosols from the new volcano circulate globally I actually could see air temps / SSTs cool off pretty quickly, with a pretty cold winter.

I've mentioned a few times that I expect the WPO to flip - at least for a while. Part of why I expect that is how warm the water is by SE Asia. At some point, the persistent ridges down there are going to get destroyed by super typhoons, and then you'll likely see compensating high pressure by NE Asia to continue directing in storms to suck up the heat content there. When will it happen? Aug-Oct is my guess, which would favor some nice cool shots for the US in that time frame. We'll see though, I haven't done extensive research on this, it's just my gut.

[Stormchaserchuck1]

1 hour ago, raindancewx said:

I've mentioned a few times that I expect the WPO to flip - at least for a while. Part of why I expect that is how warm the water is by SE Asia. At some point, the persistent ridges down there are going to get destroyed by super typhoons, and then you'll likely see compensating high pressure by NE Asia to continue directing in storms to suck up the heat content there. When will it happen? Aug-Oct is my guess, which would favor some nice cool shots for the US in that time frame. We'll see though, I haven't done extensive research on this, it's just my gut.

I just think the data kind of argues against it, especially early in the Winter. You were the one who pointed out the PDO actually has a higher correlation in the N. Pacific than ENSO.  Look at this Oct-Dec composite.. >0.6 correlation in NW Canada, going back to 1948 (not even over water)!

https://ibb.co/JHs3qrp

[snowman19]

13 hours ago, Stormchaserchuck1 said:

Models have a pretty good +AAM pattern starting early June. this may keep the La Nina peak near Moderate strength vs Strong. raindancewx has posted that we have a tendency to warm La Nina events since ~2000-05. The overall global warming trend may make it harder to see Strong La Nina events in the future, per the ONI. 

I still think the La Nina-base state that we have seen since 2000 is pretty incredible. This means that we are seeing La Nina patterns generally, even when it's not a La Nina. Some are quick to blame it on the PDO, but water is more reactive than proactive imo.   Southern Hemisphere version of the PNA has also been pretty on par with the N. Hemisphere during that time, which means that forcing might be coming from the equator.  

While it’s certainly possible that this La Niña only peaks at “high-end” moderate on the ONI, it’s looking more and more likely that the RONI is going to be strong. I also expect that the MEI will indicate a strong event given the coupling 

[40/70 Benchmark]

12 hours ago, raindancewx said:

Last year had a big heat wave in Mexico too. But it was in June, which is rare overall, but more common in the stronger El Ninos.

Global SSTs have 30-32C temps by Mexico and the Philippines right now. That's why I was thinking a couple big hurricanes may end that big high - the fuel is there if something can develop.

If we get the effects of the Tonga eruption to decay while the aerosols from the new volcano circulate globally I actually could see air temps / SSTs cool off pretty quickly, with a pretty cold winter.

I've mentioned a few times that I expect the WPO to flip - at least for a while. Part of why I expect that is how warm the water is by SE Asia. At some point, the persistent ridges down there are going to get destroyed by super typhoons, and then you'll likely see compensating high pressure by NE Asia to continue directing in storms to suck up the heat content there. When will it happen? Aug-Oct is my guess, which would favor some nice cool shots for the US in that time frame. We'll see though, I haven't done extensive research on this, it's just my gut.

That has been my theory on how the earth will correct that persistent west PAC warm pool.