2024-2025 La Nina

[michsnowfreak]

5 minutes ago, mitchnick said:

100% on that. The ground was snow covered almost all of January.  Then, February flipped warm mid month and March was around +5 at BWI. 

Maybe because I was younger in 76/77, but I found 93/94 to be even more brutal, though not as unrelenting as 76/77.

76-77 was certainly a brutal winter for cold, and I believe holds the record for longest stretch of below freezing temps. (It did warm up I'm March big time). Snowcover was good, but snowfall was nothing special, right around avg. 78-79 was another very cold winter though with snowfall actually below avg. 77-78 was definitely the harshest winter of the infamous trio, but doesn't hold a candle to 2013-14. Don't get me wrong, I would love to relive those winters for a few reasons, but from a snow perspective they were nothing special overall.

[BuffaloWeather]

Got about 3 feet today, great start to winter

[mitchnick]

This Pic of 11/25 SSTA forecast from updated Cansips is for Larry. 

 

[GaWx]

1 hour ago, mitchnick said:

This Pic of 11/25 SSTA forecast from updated Cansips is for Larry. 

 

Thanks, Mitch.

 This is the 4th run in a row showing a Modoki El Niño developing next summer fwiw. I’d also love to see the NW Pacific cool off.

[GaWx]

Latest AAM from CFS ensemble fwiw continues El Ninoish +AAM during the last half of Dec, something I like seeing as it may mean the SE ridge won’t become dominant anytime soon:

[bluewave]

The reason the modeling has been jumping around so much last few weeks is that this was the most volatile November for 500mb height changes since 1985 due to all the competing influences.

 

 

[snowman19]

@bluewave While we saw the La Niña struggle to develop all met fall, there is going to be marked strengthening and cooling this month. Full scale change with respect to ENSO/trade winds/SOI/MJO propagation and it’s going to result in a flip of the Rossby wave train we’ve been seeing up to this point:
 

[Terpeast]

All ensemble models show cold air reloading in W Canada while maintaining -EPO at the end of their runs, so any mid-month moderation may be short lived (a week, maybe 2).

[mitchnick]

36 minutes ago, Terpeast said:

All ensemble models show cold air reloading in W Canada while maintaining -EPO at the end of their runs, so any mid-month moderation may be short lived (a week, maybe 2).

Interesting how the Euro weeklies keep delaying the warmup in the east. Yesterday's run keeps the east BN or within the normal scale thru 1/6. The only AN is the week of 1/6-1/13, and only gets it into the lowest AN scale of +.5-1C. The good news being, if correct, that won't prohibited snow chances completely being so close to the climo minimum.

[Terpeast]

35 minutes ago, mitchnick said:

Interesting how the Euro weeklies keep delaying the warmup in the east. Yesterday's run keeps the east BN or within the normal scale thru 1/6. The only AN is the week of 1/6-1/13, and only gets it into the lowest AN scale of +.5-1C. The good news being, if correct, that won't prohibited snow chances completely being so close to the climo minimum.

I can see that playing out if the MJO goes into 7-8-1 and the AAM stays positive. Even a +1 C won’t be prohibitive for snowfall in the MA. 

[michsnowfreak]

6 hours ago, BuffaloWeather said:

Got about 3 feet today, great start to winter

Nice. Sounds like everything missed Buffalo officially and orchard park was slammed. 

[snowman19]

I’ll give Eric Webb credit for this, it looks like we are going to see the record strong SPV couple with the troposphere/TPV now and it moves them over the pole. Better hope he’s right that it plays out EXACTLY like 13-14 or all this is going to do is result in a very strong +AO/+NAO and lock in arctic air over the pole with no way to propagate south
 

[PhiEaglesfan712]

2 hours ago, mitchnick said:

Interesting how the Euro weeklies keep delaying the warmup in the east. Yesterday's run keeps the east BN or within the normal scale thru 1/6. The only AN is the week of 1/6-1/13, and only gets it into the lowest AN scale of +.5-1C. The good news being, if correct, that won't prohibited snow chances completely being so close to the climo minimum.

2005-06 looks like a very good analog. November 2005 perfectly fits the temperature/precipitation profile of this November.

2005-11-01	70	44	57.0	4.8	8	0	0.00	0.0	0
2005-11-02	60	43	51.5	-0.4	13	0	0.00	0.0	0
2005-11-03	67	40	53.5	2.0	11	0	0.00	0.0	0
2005-11-04	67	44	55.5	4.3	9	0	0.00	0.0	0
2005-11-05	72	47	59.5	8.7	5	0	0.00	0.0	0
2005-11-06	74	45	59.5	9.0	5	0	0.06	0.0	0
2005-11-07	62	47	54.5	4.4	10	0	0.00	0.0	0
2005-11-08	65	44	54.5	4.7	10	0	0.00	0.0	0
2005-11-09	69	53	61.0	11.6	4	0	T	0.0	0
2005-11-10	69	43	56.0	6.9	9	0	0.29	0.0	0
2005-11-11	49	38	43.5	-5.3	21	0	0.00	0.0	0
2005-11-12	58	33	45.5	-2.9	19	0	0.00	0.0	0
2005-11-13	65	41	53.0	4.9	12	0	0.00	0.0	0
2005-11-14	67	50	58.5	10.7	6	0	0.00	0.0	0
2005-11-15	71	53	62.0	14.6	3	0	T	0.0	0
2005-11-16	76	45	60.5	13.4	4	0	0.78	0.0	0
2005-11-17	46	33	39.5	-7.3	25	0	T	0.0	0
2005-11-18	40	29	34.5	-12.0	30	0	0.00	0.0	0
2005-11-19	48	29	38.5	-7.6	26	0	0.00	0.0	0
2005-11-20	59	34	46.5	0.7	18	0	0.00	0.0	0
2005-11-21	51	40	45.5	0.0	19	0	0.41	0.0	0
2005-11-22	48	36	42.0	-3.2	23	0	0.62	0.0	0
2005-11-23	37	29	33.0	-11.9	32	0	0.00	0.0	0
2005-11-24	51	24	37.5	-7.1	27	0	T	T	0
2005-11-25	34	22	28.0	-16.3	37	0	0.00	0.0	0
2005-11-26	42	25	33.5	-10.5	31	0	0.00	0.0	0
2005-11-27	53	31	42.0	-1.6	23	0	T	0.0	0
2005-11-28	69	47	58.0	14.7	7	0	T	0.0	0
2005-11-29	69	57	63.0	19.9	2	0	0.53	0.0	0
2005-11-30	63	39	51.0	8.2	14	0	0.17	0.0	0

Then, it flipped to very cold to start December, which lasted for most of the month, until it turned mild towards the end.

2005-12-01	46	36	41.0	-1.5	24	0	0.00	0.0	0
2005-12-02	42	31	36.5	-5.7	28	0	0.00	0.0	0
2005-12-03	35	26	30.5	-11.4	34	0	0.00	0.0	0
2005-12-04	39	29	34.0	-7.6	31	0	0.28	0.6	T
2005-12-05	36	30	33.0	-8.3	32	0	0.03	0.7	1
2005-12-06	37	26	31.5	-9.6	33	0	0.17	3.3	4
2005-12-07	34	23	28.5	-12.3	36	0	0.00	0.0	2
2005-12-08	32	20	26.0	-14.5	39	0	0.00	0.0	1
2005-12-09	36	25	30.5	-9.7	34	0	0.48	2.2	2
2005-12-10	35	22	28.5	-11.5	36	0	0.00	0.0	1
2005-12-11	40	25	32.5	-7.2	32	0	0.00	0.0	T
2005-12-12	39	25	32.0	-7.5	33	0	0.00	0.0	T
2005-12-13	28	17	22.5	-16.7	42	0	0.00	0.0	T
2005-12-14	24	15	19.5	-19.5	45	0	0.00	0.0	T
2005-12-15	47	17	32.0	-6.7	33	0	0.55	0.2	T
2005-12-16	53	34	43.5	5.0	21	0	0.63	0.0	0
2005-12-17	42	28	35.0	-3.2	30	0	0.00	0.0	0
2005-12-18	42	29	35.5	-2.5	29	0	0.00	0.0	0
2005-12-19	39	23	31.0	-6.7	34	0	0.00	0.0	0
2005-12-20	36	19	27.5	-10.0	37	0	0.00	0.0	0
2005-12-21	34	23	28.5	-8.8	36	0	0.00	0.0	0
2005-12-22	38	26	32.0	-5.1	33	0	0.00	0.0	0
2005-12-23	51	30	40.5	3.7	24	0	0.00	0.0	0
2005-12-24	55	30	42.5	5.9	22	0	0.00	0.0	0
2005-12-25	55	27	41.0	4.6	24	0	0.40	0.0	0
2005-12-26	47	41	44.0	7.8	21	0	0.02	0.0	0
2005-12-27	47	36	41.5	5.5	23	0	0.00	0.0	0
2005-12-28	52	30	41.0	5.2	24	0	0.00	0.0	0
2005-12-29	49	43	46.0	10.4	19	0	0.30	0.0	0
2005-12-30	48	34	41.0	5.6	24	0	0.00	0.0	0
2005-12-31	40	33	36.5	1.2	28	0	0.11	0.0	0

January turned out to be a torch: 

2006-01-01	45	31	38.0	2.9	27	0	0.00	0.0	0
2006-01-02	45	28	36.5	1.6	28	0	0.92	0.0	0
2006-01-03	45	36	40.5	5.8	24	0	0.45	0.0	0
2006-01-04	43	35	39.0	4.4	26	0	T	0.0	0
2006-01-05	51	37	44.0	9.6	21	0	T	0.0	0
2006-01-06	43	32	37.5	3.2	27	0	0.00	0.0	0
2006-01-07	36	22	29.0	-5.2	36	0	0.00	0.0	0
2006-01-08	46	34	40.0	6.0	25	0	0.00	0.0	0
2006-01-09	60	37	48.5	14.6	16	0	0.00	0.0	0
2006-01-10	50	36	43.0	9.2	22	0	0.00	0.0	0
2006-01-11	53	34	43.5	9.8	21	0	0.37	0.0	0
2006-01-12	58	39	48.5	14.9	16	0	0.00	0.0	0
2006-01-13	59	35	47.0	13.5	18	0	0.00	0.0	0
2006-01-14	60	32	46.0	12.6	19	0	0.53	0.2	0
2006-01-15	34	25	29.5	-3.8	35	0	0.02	0.2	T
2006-01-16	32	20	26.0	-7.3	39	0	0.00	0.0	T
2006-01-17	50	27	38.5	5.3	26	0	0.03	0.0	0
2006-01-18	64	35	49.5	16.3	15	0	0.72	0.0	0
2006-01-19	52	33	42.5	9.3	22	0	0.00	0.0	0
2006-01-20	57	36	46.5	13.4	18	0	0.00	0.0	0
2006-01-21	61	37	49.0	15.9	16	0	0.00	0.0	0
2006-01-22	46	31	38.5	5.4	26	0	0.03	0.0	0
2006-01-23	43	35	39.0	5.9	26	0	1.04	0.0	0
2006-01-24	47	32	39.5	6.4	25	0	0.09	T	0
2006-01-25	41	33	37.0	3.8	28	0	0.00	0.0	0
2006-01-26	36	27	31.5	-1.7	33	0	0.00	0.0	0
2006-01-27	44	23	33.5	0.3	31	0	0.00	0.0	0
2006-01-28	59	30	44.5	11.2	20	0	0.00	0.0	0
2006-01-29	55	33	44.0	10.6	21	0	0.13	0.0	0
2006-01-30	62	37	49.5	16.1	15	0	T	0.0	0
2006-01-31	46	41	43.5	10.0	21	0	0.01	0.0	0

 

[bluewave]

4 hours ago, snowman19 said:

@bluewave While we saw the La Niña struggle to develop all met fall, there is going to be marked strengthening and cooling this month. Full scale change with respect to ENSO/trade winds/SOI/MJO propagation and it’s going to result in a flip of the Rossby wave train we’ve been seeing up to this point:
 

The November warming with the record EPAC WWB back in December is fading as the Niña-like EWBs are returning. You can see the +AAM influence beginning to weaken after early December. The 500 mb pattern is starting resemble something more Niña-like.

New run around the 10th showing weakening +AAM influence and taking on some Niña-like elements like higher heights near the East Coast and a more +WPO

 

 

Older run stronger +AAM with deeper Eastern Trough and more -WPO

 

 

Nino 3.4 shifting back to cold neutral from warm neutral

[Terpeast]

5 minutes ago, bluewave said:

The November warming with the record EPAC WWB back in December is fading as the Niña-like EWBs are returning. You can see the +AAM influence beginning to weaken after early December. The 500 mb pattern is starting resemble something more Niña-like.

New run around the 10th showing weakening +AAM influence and taking on some Niña-like elements like higher heights near the East Coast and a more +WPO

 

 

Older run stronger +AAM with deeper Eastern Trough and more -WPO

 

 

I think that is a low confidence outlook given that the AAM’s weakening is forecast to only be temporary. Although the Dec 10 “moderation” coincides with the AAM going neutral, the CFS is projecting the +AAM to restrengthen after mid-Dec.

[bluewave]

6 minutes ago, Terpeast said:

I think that is a low confidence outlook given that the AAM’s weakening is forecast to only be temporary. Although the Dec 10 “moderation” coincides with the AAM going neutral, the CFS is projecting the +AAM to restrengthen after mid-Dec.

While I am not a fan of using the CFS model, its forecast 500mb pattern at that time looks more like -AAM. 

[Terpeast]

1 minute ago, bluewave said:

While I am not a fan of using the CFS model, its forecast 500mb pattern at that time looks more like -AAM. 

Either way, low confidence. It’s not going to be as clear cut as we thought it would be even a month ago when it looked like another record warm winter through and through. It’s looking more like there will be a couple of surprise curveballs along the way. Not saying it’ll be a BN winter/AN snowfall in the east, I’m sticking with my AN temps and BN snow outlook, but probably not as bad as we thought.

[snowman19]

24 minutes ago, Terpeast said:

Either way, low confidence. It’s not going to be as clear cut as we thought it would be even a month ago when it looked like another record warm winter through and through. It’s looking more like there will be a couple of surprise curveballs along the way. Not saying it’ll be a BN winter/AN snowfall in the east, I’m sticking with my AN temps and BN snow outlook, but probably not as bad as we thought.

I never thought this winter was going to be a full on wall to wall torch, that’s why I went with +2 - +4 for temps from Dec-Mar with below average snow. That said, I think the pattern becomes much more La Niña like mid-month and beyond given the waning AAM and EWBs/ENSO 3.4 cooling/MJO forcing/SOI developments. I also firmly believe that once that process gets going, AAM is going to drop significantly from what is being shown right now. There is going to be a lag effect. IMO the models get warmer than what is currently depicted today for mid-late month. As @bluewave pointed out in the NYC thread, the weeklies are already backing off the cooler pattern they had yesterday. Unlike Eric Webb, I see the models now going for SPV/TPV coupling and the SPV being record strong as a bad thing. Unless we see a exact replica of 13-14 (unlikely IMO), that coupling is going to lock the NAO/AO positive and trap the arctic air over the pole with no mechanism to readily bring it south

[yoda]

 

 

[GaWx]

Todays Euro Weekly at H5 for 1/6-12 looks pretty good:

 

[mitchnick]

GEFS having a hard time making up it's mind in the long range between runs.

End of the 12z run 850 anomalies on top and end of the 18z on the bottom. 

500mb maps with similar looks.

[Terpeast]

24 minutes ago, mitchnick said:

GEFS having a hard time making up it's mind in the long range between runs.

End of the 12z run 850 anomalies on top and end of the 18z on the bottom. 

500mb maps with similar looks.

Yeah, the models have been pretty shaky and I think thats going to be the story of the entire winter. 

[GaWx]

Natural gas is down 6% this evening, which is usually at this time of year indicative of reduced cold in the two week forecast, especially toward the end of week two.

[Stormchaserchuck1]

25 minutes ago, GaWx said:

Natural gas is down 6% this evening, which is usually at this time of year indicative of reduced cold in the two week forecast, especially toward the end of week two.

Definitely feeling like we are going to start to enter a warm pattern.  There was a lot of stuff in the Summer pointing to a +NAO Winter, and that's starting to flash some signs in the long range. If that gets going with -PNA, it could get really warm around Christmas. I would even say there is probably a >50% chance that the Northeast finishes December near average to slightly above in temperatures.  I was kind of surprised that the CPC went cold for December yesterday, because this 2 week below average stretch is the only time we have seen such a thing in the continental US in over a year!

[Stormchaserchuck1]

Here you go Larry

https://x.com/WestSeaWx/status/1863471992156160321?ref_src=twsrc^tfw|twcamp^tweetembed|twterm^1863471992156160321|twgr^007f217bf200f801e3d5d3c535e0dc0db720024d|twcon^s1_&ref_url=https%3A%2F%2Ftheweatherforums.com%2Findex.php%3Fapp%3Dcoremodule%3Dsystemcontroller%3Dembedurl%3Dhttps%3A%2F%2Fx.com%2FWestSeaWx%2Fstatus%2F1863471992156160321

[bluewave]

20 hours ago, Terpeast said:

Either way, low confidence. It’s not going to be as clear cut as we thought it would be even a month ago when it looked like another record warm winter through and through. It’s looking more like there will be a couple of surprise curveballs along the way. Not saying it’ll be a BN winter/AN snowfall in the east, I’m sticking with my AN temps and BN snow outlook, but probably not as bad as we thought.

The +AAM influence will start to fade since it was just a brief pattern driver which emerged for a few weeks from late November into early December. Just like the models originally underestimated the event from back in mid-November when it wasn’t showing up. Now we can see they have been underestimating the return of the milder La Niña background pattern from last week. This also matches the December seasonal progression that I posted on yesterday in the NYC Metro forum. The WPAC warm pool continues to be a dominant force as we have seen since the 15-16 winter. So it’s difficult for us to get more than a week or two of cold at a time before the warmth returns. But it will be interesting to see if there will be some more +AAM intervals to at least push back against the milder La Niña pattern at times after December.

[Terpeast]

1 hour ago, bluewave said:

The +AAM influence will start to fade since it was just a brief pattern driver which emerged for a few weeks from late November into early December. Just like the models originally underestimated the event from back in mid-November when it wasn’t showing up. Now we can see they have been underestimating the return of the milder La Niña background pattern from last week. This also matches the December seasonal progression that I posted on yesterday in the NYC Metro forum. The WPAC warm pool continues to be a dominant force as we have seen since the 15-16 winter. So it’s difficult for us to get more than a week or two of cold at a time before the warmth returns. But it will be interesting to see if there will be some more +AAM intervals to at least push back against the milder La Niña pattern at times after December.

I think extra variability will be the story of this winter. For now, the warm pool via MJO 5-6 is starting to exert its influence, but as I’ve been saying for almost a month now, the period I’m watching is when the MJO completes its pass through 6 entering 7/8/1 and the +AAM comes back at the same time. Still estimate that to be late Dec - early Jan, but sometimes models rush a pattern change, so it could be after the New Year. 

I could be wrong about the specifics, but again I think we’re going to see more variability. 

[40/70 Benchmark]

10 minutes ago, Terpeast said:

I think extra variability will be the story of this winter. For now, the warm pool via MJO 5-6 is starting to exert its influence, but as I’ve been saying for almost a month now, the period I’m watching is when the MJO completes its pass through 6 entering 7/8/1 and the +AAM comes back at the same time. Still estimate that to be late Dec - early Jan, but sometimes models rush a pattern change, so it could be after the New Year. 

I could be wrong about the specifics, but again I think we’re going to see more variability. 

I am on the same page as you.

[40/70 Benchmark]

1 hour ago, bluewave said:

The +AAM influence will start to fade since it was just a brief pattern driver which emerged for a few weeks from late November into early December. Just like the models originally underestimated the event from back in mid-November when it wasn’t showing up. Now we can see they have been underestimating the return of the milder La Niña background pattern from last week. This also matches the December seasonal progression that I posted on yesterday in the NYC Metro forum. The WPAC warm pool continues to be a dominant force as we have seen since the 15-16 winter. So it’s difficult for us to get more than a week or two of cold at a time before the warmth returns. But it will be interesting to see if there will be some more +AAM intervals to at least push back against the milder La Niña pattern at times after December.

I feel pretty good about December relative to my expectation, although I will probably be a bit too warm due to the unanticipated magnitude of that WWB.

The lower and of my +3 to +5 my still work.

[bluewave]

13 minutes ago, Terpeast said:

I think extra variability will be the story of this winter. For now, the warm pool via MJO 5-6 is starting to exert its influence, but as I’ve been saying for almost a month now, the period I’m watching is when the MJO completes its pass through 6 entering 7/8/1 and the +AAM comes back at the same time. Still estimate that to be late Dec - early Jan, but sometimes models rush a pattern change, so it could be after the New Year. 

I could be wrong about the specifics, but again I think we’re going to see more variability. 

Will be interesting to see if extended GEFS is correct and we can get the forcing east of the Dateline in January and have the warmer Maritime Continent influence begin to weaken by then.