2024-2025 La Nina

[michsnowfreak]

With all the talk of 2007-08 I wish we could find a seasonal snowfall map of the US. The gradient must have been something with the very heavy to record snowfall in the Great Lakes and new England and then crap south of NYC

[raindancewx]

I don't like 2007-08 much as an analog but this is what snow looks like.

[snowman19]

5 hours ago, so_whats_happening said:

I feel like I have seen now a few times 2013-14 get thrown around. Quite interesting to say the least so far it is fairly close in matching this August/September 500mb pattern. Hurricane season ended up 14/2/0, we already had 1 major hurricane so there is that at least. Already had a pretty well established westerly QBO. -PDO was around, we are on a different magnitude of PDO right now but we shall see how it continues. Entering a solar max time period. A bit off on the subsurface look as this year has a bit more of negative subsurface. 

Again just pointing out some similarities no real drive to make this a forecast. If models are right in signaling and we do indeed actually start to see more troughing occur onto the Pac NW this may be a year to throw into the consensus.

Even though 13-14 (cold-neutral) was “technically” a -PDO it sure did not behave like one on the PAC side, in fact, it exactly mimicked a +PDO and a real strong one at that. The PAC SST configuration was completely different than what we are seeing now, which caused that very strong +PDO/+TNH response. Classic +TNH in fact. @bluewave made a post a little over a month ago explaining the reasons for it. The Atlantic side is definitely similar and it ended up being ++NAO/++AO that winter. It was all Pacific driven 

[40/70 Benchmark]

5 hours ago, so_whats_happening said:

2007 is a bit off to me but here is the 500mb pattern for August/September. That year we had a late developing WQBO pattern, rather low solar year, the PDO was rather neutral except a random spike negative around October, subsurface was an ok match, the hurricane season put on quite the show. So it has some similarities maybe an anti 2007 would be better?

I think 2007 is a pretty good analog...not perfect. Not a huge fan of 2013.

[40/70 Benchmark]

1 hour ago, snowman19 said:

Even though 13-14 (cold-neutral) was “technically” a -PDO it sure did not behave like one on the PAC side, in fact, it exactly mimicked a +PDO and a real strong one at that. The PAC SST configuration was completely different than what we are seeing now, which caused that very strong +PDO/+TNH response. Classic +TNH in fact. @bluewave made a post a little over a month ago explaining the reasons for it. The Atlantic side is definitely similar and it ended up being ++NAO/++AO that winter. It was all Pacific driven 

Agree. Perhaps the WPO/EPO behave similarly, but I think the PDO and La Nina are bad matches. 

[so_whats_happening]

1 hour ago, snowman19 said:

Even though 13-14 (cold-neutral) was “technically” a -PDO it sure did not behave like one on the PAC side, in fact, it exactly mimicked a +PDO and a real strong one at that. The PAC SST configuration was completely different than what we are seeing now, which caused that very strong +PDO/+TNH response. Classic +TNH in fact. @bluewave made a post a little over a month ago explaining the reasons for it. The Atlantic side is definitely similar and it ended up being ++NAO/++AO that winter. It was all Pacific driven 

It was a rather massive change in SST's that year alot can still happen.

[PhiEaglesfan712]

5 hours ago, so_whats_happening said:

2007 is a bit off to me but here is the 500mb pattern for August/September. That year we had a late developing WQBO pattern, rather low solar year, the PDO was rather neutral except a random spike negative around October, subsurface was an ok match, the hurricane season put on quite the show. So it has some similarities maybe an anti 2007 would be better?

I don't know if I said this before, but anti-2007 gets us an el nino:

[so_whats_happening]

Just now, PhiEaglesfan712 said:

I don't know if I said this before, but anti-2007 gets us an el nino:

I am unsure. I do my best to pay attention to what folks say in here but I unfortunately have a lot going on outside of this to where I can only keep up so much.

[Stormchaserchuck1]

44 minutes ago, so_whats_happening said:

It was a rather massive change in SST's that year alot can still happen.

Interesting that 13-14 was cold ENSO right in that spot where I think it has it has a cold correlation

I've posted this before but anti-Strong El Nino's: 

Furthermore, there is not much of a PDO correlation when the highest SSTA's are over that equilateral Pacific coldest water region

I contest that true El Nino's (warmest anomaly over equilatoral Pac coldest SST region) are warmer than people think, and true La Nina's are colder than people think. Furthermore, if you go all the way east-based with Nino 1+2 as the dominant region, the mid-latitude cell effect directly north of it is actually over North America, not the Pacific Ocean. Something to keep in mind going forward.. if the La Nina remains strongest in Nino 3.  I think a lot of the seasonal models are looking for feedback from the -PDO, trying to make it more west-based.. 

[snowman19]

8 hours ago, 40/70 Benchmark said:

I think 2007 is a pretty good analog...not perfect. Not a huge fan of 2013.

Besides the cold-neutral state, if I’m not mistaken the IOD was positive, which may have helped alter the MJO forcing in 13-14 too, in addition to the very different PDO configuration. That winter was not only predominant -WPO/-EPO, the PNA also went through the roof positive at times, I believe there were +3 +PNA spikes that winter if I remember correctly. The PAC side saved that winter, the NAO/AO were severely positive all winter. I very, very seriously doubt we see a Pacific pattern anywhere close to that one this winter 

[mitchnick]

1 hour ago, snowman19 said:

Besides the cold-neutral state, if I’m not mistaken the IOD was positive, which may have helped alter the MJO forcing in 13-14 too, in addition to the very different PDO configuration. That winter was not only predominant -WPO/-EPO, the PNA also went through the roof positive at times, I believe there were +3 +PNA spikes that winter if I remember correctly. The PAC side saved that winter, the NAO/AO were severely positive all winter. I very, very seriously doubt we see a Pacific pattern anywhere close to that one this winter 

I don't think anybody is saying it's a perfect match, just that there are enough similarities to put it in the mix.

[bluewave]

11 hours ago, snowman19 said:

Even though 13-14 (cold-neutral) was “technically” a -PDO it sure did not behave like one on the PAC side, in fact, it exactly mimicked a +PDO and a real strong one at that. The PAC SST configuration was completely different than what we are seeing now, which caused that very strong +PDO/+TNH response. Classic +TNH in fact. @bluewave made a post a little over a month ago explaining the reasons for it. The Atlantic side is definitely similar and it ended up being ++NAO/++AO that winter. It was all Pacific driven 

Yeah, very strong cold pool near Japan was something we haven’t seen in years with the ongoing record marine heatwave there. The only two summers I could find with a similar 500 mb pattern to this summer were 2021 and 2022. You can see how 2013 was reversed in the North Pacific. Very strong ridge over the Bering and Alaska instead of the trough this summer. 

 

[PhiEaglesfan712]

Anti-1986/1987 analog: 

 vs. 2007:

 

Starting from the Dakotas/Texas and all the way eastward, this is nearly a perfect match.

[snowman19]

The Atlantic continues to look deader than a doornail. If we end up below 100 ACE for the season, it will be one of the most epic forecast busts of all time for a lot of people….

[Stormchaserchuck1]

@40/70 Benchmark See how the -NAO is correlating with -PNA/+EPO. The RNA flexed here, compared to before, when the pattern becomes predominant. It's not perfect, but there is a correlation in place. 

https://www.meteo.psu.edu/ewall/ENSHGTAVGNH_0z/ensloopmref.html

[Stormchaserchuck1]

We are also seeing this strong -PNA pattern for the next 15 days as the ENSO subsurface is cooling again.. 30-day SOI finally made it above 10. 

It seems to be re-organizing further west. This is actually quite a west-based cold pool for this time of year. Imo, that could slim the chances for warm ENSO next year. It also makes it more probable that the La Nina tries to become more west-based at the surface in the coming months. 

I'm thinking a more west-based subsurface cold pool/La Nina may actually weaken the chances for a -EPO Winter.. we'll have to see how it evolves in the coming time. Those +SSTAs near Japan are very +WPO. 

All I have going for that counter-argument is that the state of the WPO/EPO usually flips after a long, sustained phase, which have seen on both monthly and yearly scales, and this is the time period where it usually happens. 

[Stormchaserchuck1]

Best SOI match I can find where it didn't do much all year then started going positive in the Fall is 2007.. If someone has done more in depth research in that regard, correct me if I'm wrong. 1999 waned in the Spring/Summer then strengthened again in the Fall. That's about all I could find going back to 1950. It usually starts going into a phase earlier. 

[GaWx]

 Can anyone explain why the difference between the cold biased CDAS and the OISST is relatively large currently? It is near the largest of the last few months it appears (0.45):

CDAS

OISST:

[40/70 Benchmark]

3 hours ago, Stormchaserchuck1 said:

@40/70 Benchmark See how the -NAO is correlating with -PNA/+EPO. The RNA flexed here, compared to before, when the pattern becomes predominant. It's not perfect, but there is a correlation in place. 

https://www.meteo.psu.edu/ewall/ENSHGTAVGNH_0z/ensloopmref.html

Yea, I never doubted you on that....I recall all too vividly how many times RNA has deprived us the spoils of the NAO blocking over the course of the past few seasons....especially in 12/22 and 3/23.

[40/70 Benchmark]

2 hours ago, Stormchaserchuck1 said:

This is actually quite a west-based cold pool for this time of year. Imo, that could slim the chances for warm ENSO next year. It also makes it more probable that the La Nina tries to become more west-based at the surface in the coming months. 

I have always thought that was a given-

Its still a bit more east-based than I thought it would be, which should change.

[40/70 Benchmark]

2 hours ago, Stormchaserchuck1 said:

Best SOI match I can find where it didn't do much all year then started going positive in the Fall is 2007.. If someone has done more in depth research in that regard, correct me if I'm wrong. 1999 waned in the Spring/Summer then strengthened again in the Fall. That's about all I could find going back to 1950. It usually starts going into a phase earlier. 

Both good analogs IMO.

[bluewave]

14 minutes ago, 40/70 Benchmark said:

Yea, I never doubted you on that....I recall all too vividly how many times RNA has deprved us the spoils of the NAO blocking over the course of the past few seasons....especially in 12/22 and 3/23.

The more amplified Aleutian Ridge and much warmer Atlantic has made the -PNA -NAO much less favorable than it was back in the older -PDO era. These days any deep trough near the West Coast pumps the Southeast Ridge. In the old days the much cooler SSTs prevented Southeast Ridge formation in most circumstances when the AO and NAO were negative.
 

[40/70 Benchmark]

6 minutes ago, bluewave said:

The more amplified Aleutian Ridge and much warmer Atlantic has made the -PNA -NAO much less favorable than it was back in the older -PDO era. These days any deep trough near the West Coast pumps the Southeast Ridge. In the old days the much cooler SSTs prevented Southeast Ridge formation in most circumstances when the AO and NAO were negative.
 

Yes...I was skeptical of that 2 years ago, but I'm now ready to buy that element of CC after getting burned badly. However, I think for New England its still not as bad as it appears because there was some bad luck. Mid Atl its game over in that pattern now....and def. more precarious for SNE.

[snowman19]

3 hours ago, Stormchaserchuck1 said:

We are also seeing this strong -PNA pattern for the next 15 days as the ENSO subsurface is cooling again.. 30-day SOI finally made it above 10. 

It seems to be re-organizing further west. This is actually quite a west-based cold pool for this time of year. Imo, that could slim the chances for warm ENSO next year. It also makes it more probable that the La Nina tries to become more west-based at the surface in the coming months. 

I'm thinking a more west-based subsurface cold pool/La Nina may actually weaken the chances for a -EPO Winter.. we'll have to see how it evolves in the coming time. Those +SSTAs near Japan are very +WPO. 

All I have going for that counter-argument is that the state of the WPO/EPO usually flips after a long, sustained phase, which have seen on both monthly and yearly scales, and this is the time period where it usually happens. 

Agree about the ENSO configuration. If you compare the subsurface now to 2017 (a true east-based event), it’s not even remotely close

[PhiEaglesfan712]

34 minutes ago, 40/70 Benchmark said:

Yea, I never doubted you on that....I recall all too vividly how many times RNA has deprived us the spoils of the NAO blocking over the course of the past few seasons....especially in 12/22 and 3/23.

It sucked that the 12/22 block was the short term one and the 3/23 one was long term. It just took too long for all the pieces on the latter block to come together. If the 3/23 block happened in 12/22 instead, and developed the way it did, late January through March would have been cold and snowy during the parts when it wasn't dry.

[40/70 Benchmark]

2 minutes ago, PhiEaglesfan712 said:

It sucked that the 12/22 block was the short term one and the 3/23 one was long term. It just took too long for all the pieces on the latter block to come together. If the 3/23 block happened in 12/22 instead, and developed the way it did, late January through March would have been cold and snowy during the parts when it wasn't dry.

I think you overstate the significance of the timing. The very amplifed pattern out west was the much larger issue than the timing....it sucked in December and it sucked in March. You aren't getting much snow in the mid atl with a trough that deep out west...doesn't matter when it is.

[roardog]

1 hour ago, GaWx said:

 Can anyone explain why the difference between the cold biased CDAS and the OISST is relatively large currently? It is near the largest of the last few months it appears (0.45):

CDAS

OISST:

It’s not just in the enso regions either, there’s a big difference globally now it seems. 

[snowman19]

40 minutes ago, roardog said:

It’s not just in the enso regions either, there’s a big difference globally now it seems. 

This is the 1st time in a long time that Nino region 4 is negative

[mitchnick]

1 hour ago, snowman19 said:

This is the 1st time in a long time that Nino region 4 is negative

Been many a year that Hudson Bay has seen such cooling this time of year fwiw. Surprisingly, Coral Reef and Oisst agree on it too. Too early to say for sure, but it does suggest a cool to cold Canada this winter reflected on the Cansips and Cfs2 may be in the works.

[40/70 Benchmark]

5 minutes ago, mitchnick said:

Been many a year that Hudson Bay has seen such cooling this time of year fwiw. Surprisingly, Coral Reef and Oisst agree on it too. Too early to say for sure, but it does suggest a cool to cold Canada this winter reflected on the Cansips and Cfs2 may be in the works.

That fuels my idea about a potential 2007-2008 get out of fail free card for parts of NE if all else goes to shit.