2024-2025 La Nina

[40/70 Benchmark]

35 minutes ago, bluewave said:

I don’t think it’s a coincidence that the rapid warming of the subtropical Pacific and Atlantic occurred with the super El Niño temperature jump in 15-16. This warming has been associated with the rapid expansion of the subtropical ridge near the East Coast of the U.S. and East of Japan to south of the Aleutians. This pattern has only become reinforced by the further record global temperature jump over the past 15 to 18 months. So this could be the result of a threshold effect related to the much warmer base state. It’s why the North Pacific pattern is so different from past -PDO instances.

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2022GL101078

The Pacific Decadal Oscillation (PDO) is a widely used measure of the temperature variability in the North Pacific Ocean. The PDO is the result of a well-known technique called empirical orthogonal function (EOF) analysis that isolates the most energetic modes of variability of the analyzed variable. The first time EOF analysis was applied to oceanographic data was in the 1970's when it was used to identify the most energetic modes of North Pacific sea surface temperature (SST). The first EOF of North Pacific SST has proved so useful as a measure that it received the moniker PDO. Our analysis suggests that a period of persistent marine heatwaves in the North Pacific since 2014 has been so powerful that this first mode of variability of SST has fundamentally changed and the PDO may not be as useful an indicator as it once was.

 

Thanks for that article by the way....I referenced it a couple of times in my work this season.

[snowman19]

@Gawx Even more confidence in my guess of a hostile NAO this winter. And any word on the October QBO number?

Edit: @GaWx Assuming a Dec/Jan peak, I wonder if we meet or eclipse the WQBO record (at 30mb) of +15??
 

[snowman19]

16 hours ago, GaWx said:

 Today’s Euro Weeklies mean, while warm dominated til the end once again, have a change late (not on prior runs) toward a weakening SPV that approaches the climo avg fwiw:

Hard sell on the SPV weakening. The Euro was awful with doing this last year early on in November/December. And there’s a massive trough in Eurasia exactly where you would want a ridge, which is going to allow the SPV to strengthen as much as it wants

[bluewave]

1 hour ago, 40/70 Benchmark said:

Thanks for that article by the way....I referenced it a couple of times in my work this season.

I am glad you were able to use it. The Euro seasonal that just updated continues this expanded subtropical ridge and marine heatwave pattern for the entire run. While not looking at exact temperature departures and 500 mb height anomalies, it’s noteworthy how little cold air is available in the Northern Hemisphere for the winter forecast in the means.

 

 

 

 

[qg_omega]

14 hours ago, 40/70 Benchmark said:

I'm about halfway home on this year's effort...bringing a renewed perspective this year that is less ENSO saturated and more CC conscious. Hope to post early next week.

Nothing has changed, maritime heatwave if anything is strongest its ever been.  Warm and snow less winter is on its way +4 to +8.

[qg_omega]

23 minutes ago, bluewave said:

I am glad you were able to use it. The Euro seasonal that just updated continues this expanded subtropical ridge and marine heatwave pattern for the entire run. While not looking at exact temperature departures and 500 mb height anomalies, it’s noteworthy how little cold air is available in the Northern Hemisphere for the winter forecast in the means.

 

 

 

 

one of the easiest winter forecasts in a long time, look at last year and the year before and extrapolate forward.

[40/70 Benchmark]

Just now, qg_omega said:

one of the easiest winter forecasts in a long time, look at last year and the year before and extrapolate forward.

Eh...last year was utterly hopeless, but the year before wasn't far off from a decent season where I am.

[PhiEaglesfan712]

October 2021 -> November 2024 (uber warm month)

November 2021 -> December 2024 (cool, but mostly dry month)

December 2021 -> January 2025 (uber warm month)

January 2022 -> February 2025 (mismatch month, cold and snowy)

Overall, the winter will be warmer than average, but it won't be warm throughout. I see a 1"-3" early December snowstorm in the mid-Atlantic, with Arctic air coming immediately thereafter. January is going to be warm. The winter will hinge on whether we get a January 2022/February 2021 type mismatch in February 2025. If we don't, then this winter will be a huge bust and FMA will be 3-5 degrees above average.

[snowman19]

@40/70 Benchmark

This is going to become even more of a classic central-based Niña
 

[GaWx]

1 hour ago, snowman19 said:

Hard sell on the SPV weakening. The Euro was awful with doing this last year early on in November/December. And there’s a massive trough in Eurasia exactly where you would want a ridge, which is going to allow the SPV to strengthen as much as it wants

 I’m not necessarily buying into it. I just thought it was semi-noteworthy enough to post due to the change. It’s just one run (they often jump around) and it weakens it only to near normal at that not til the low accuracy end of the period. Even if it were to verify, it could go right back to strong obviously as ups and downs are common. In the meantime even it still suggests a mainly strong SPV for Nov 20 through Dec 15th. I’ll see what future runs show as I look for model trends like I usually do.

[GaWx]

 The newest WB Euro seasonal for winter is a bit warmer than the run from Oct for the Mid Atlantic, NE, and especially the Midwest (Dec and Feb are warmer than the prior run had while Jan is not as warm):

Here was last month’s run:

[bluewave]

The record subsurface warmth east of Japan goes down a remarkable 300 meters making it very difficult to shift.

 

 

 

[donsutherland1]

ECMWF Winter (December-February) Forecasts:

From October:

 

Latest:

[GaWx]

13 minutes ago, donsutherland1 said:

ECMWF Winter (December-February) Forecasts:

From October:

 

Latest:

Are you aware of a warmer E US outlook for winter from the Euro as of Nov 1st for past winters?

[michsnowfreak]

3 hours ago, PhiEaglesfan712 said:

October 2021 -> November 2024 (uber warm month)

November 2021 -> December 2024 (cool, but mostly dry month)

December 2021 -> January 2025 (uber warm month)

January 2022 -> February 2025 (mismatch month, cold and snowy)

Overall, the winter will be warmer than average, but it won't be warm throughout. I see a 1"-3" early December snowstorm in the mid-Atlantic, with Arctic air coming immediately thereafter. January is going to be warm. The winter will hinge on whether we get a January 2022/February 2021 type mismatch in February 2025. If we don't, then this winter will be a huge bust and FMA will be 3-5 degrees above average.

Initially I was thinking we were due for a more frontloaded winter, especially as those can happen in Ninas, but with latest trends Im actually liking December less and January more.

[donsutherland1]

4 minutes ago, GaWx said:

Are you aware of a warmer E US outlook for winter from the Euro as of Nov 1st for past winters?

There has been none warmer than the current outlook. But the archived data only goes back to November 2017.

[SnoSki14]

If these warm/dry winter forecasts are correct then we're looking at a massive drought and fire spring season, worse than 01/02

[GaWx]

18 minutes ago, SnoSki14 said:

If these warm/dry winter forecasts are correct then we're looking at a massive drought and fire spring season, worse than 01/02

 The good news is that the Euro has a much stronger warm signal than dry signal in the NE US. At most some of the NE is barely in the lightest BN shade. So, there’s almost no signal to no signal on precip. there. There is a more notable dry signal in the SE US, especially deeper SE, which is consistent with La Niña climo.

[GaWx]

4 hours ago, snowman19 said:

@Gawx Even more confidence in my guess of a hostile NAO this winter. And any word on the October QBO number?
 

Yes, QBO rose from Sep’s +8.61 to Oct’s +10.36 (at 30 mb):

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

 My latest guess is for the peak month to be Dec with the most likely range for peak month being Nov-Jan.

[michsnowfreak]

11 minutes ago, GaWx said:

 The good news is that the Euro has a much stronger warm signal than dry signal in the NE US. At most some of the NE is barely in the lightest BN shade. So, there’s almost no signal to no signal on precip.

The Euro is the warmest seasonal forecast in the north, but also their forecast is always far too broadbrushed (almost more like a probability forecast). The cfs/cansips are much colder in the north. As for precip, cansips seems to be the driest for the east coast. Cfs/euro aren't too bad. 

[bluewave]

The Euro forecast was much too cold for last winter as it only had +1C anomaly over the Upper Midwest where a +5C anomaly verified. It would have looked more dramatic if the forecast was in F instead. So the takeaway is that the Euro during recent years has been significantly underestimating the warm departures under the strongest 500mb height anomalies. So we’ll probably have to wait and see where the main ridge axis sets up and then adjust warmer. The only time the Euro wasn’t biased too cold in recent years was during mismatch patterns when the 500mb pattern went against the La Niña and -PDO.  

 

[michsnowfreak]

34 minutes ago, bluewave said:

The Euro forecast was much too cold for last winter as it only had +1C anomaly over the Upper Midwest where a +5C anomaly verified. It would have looked more dramatic if the forecast was in F instead. So the takeaway is that the Euro during recent years has been significantly underestimating the warm departures under the strongest 500mb height anomalies. So we’ll probably have to wait and see where the main ridge axis sets up and then adjust warmer. The only time the Euro wasn’t biased too cold in recent years was during mismatch patterns when the 500mb pattern went against the La Niña and -PDO.  

 

Even the euro, by far the warmest of the seasonal models for the northern US & Canada, is much cooler in western and southern Canada this winter, which is always a good sign for good periods in the northern US.

[bluewave]

6 minutes ago, michsnowfreak said:

Even the euro, by far the warmest of the seasonal models for the northern US & Canada, is much cooler in western and southern Canada this winter, which is always a good sign for good periods in the northern US.

I think that is just due to this being a La Niña instead of an El Niño.

[michsnowfreak]

32 minutes ago, bluewave said:

I think that is just due to this being a La Niña instead of an El Niño.

I agree. But it's still good for the northern US. It's what causes those nina crazy temp gradients.

[qg_omega]

1 hour ago, michsnowfreak said:

I agree. But it's still good for the northern US. It's what causes those nina crazy temp gradients.

Not this year

[michsnowfreak]

26 minutes ago, qg_omega said:

Not this year

Oh I have no doubt itll be an excellent snow year for the northern Lakes. For the southern Lakes there are some things I like and some things I don't like.

[qg_omega]

5 minutes ago, michsnowfreak said:

Oh I have no doubt itll be an excellent snow year for the northern Lakes. For the southern Lakes there are some things I like and some things I don't like.

It won’t be

[Stormchaserchuck1]

6z and 12z GFS ensemble mean develop a huge Aleutian Ridge, -PNA, days 13-16, Nov 18-21. It's a pretty impressive signal, >+250dm on the mean. Should hold a ridge on the east coast through the end of November if it verifies. 

[michsnowfreak]

15 minutes ago, qg_omega said:

It won’t be

I forgot I was talking to someone who is post-limited and doesn't actually save those posts for anything other than trolling.

[40/70 Benchmark]

22 hours ago, snowman19 said:

@40/70 Benchmark

This is going to become even more of a classic central-based Niña
 

Yea, we have been saying that for a while now...I'm beginning to have some last second reservations about it TBH...especially with respect to intensity.