2024-2025 La Nina

[40/70 Benchmark]

19 minutes ago, donsutherland1 said:

Yes. I also, felt odds leaned cold in the East. From 11/24 in this thread: "Therefore, the odds are now tilted toward a cooler than normal December in the eastern third of the U.S. including such cities as Philadelphia, New York City, Buffalo, Chicago, Detroit, and Indianapolis, among others. Toronto could also wind up colder than normal."

Yea, I think there was a solid consensus on a cold start....no shock there. Now, if the month were to finish with a negative departure, then different story.

[Maestrobjwa]

8 hours ago, 40/70 Benchmark said:

I'm not sure why La Nina has to automatically mean relentless blowtorch from latter January through March...I don't think that will be the case.

Recency bias fron 2022-23? Lol But that seemed extreme even by nina standards.

[40/70 Benchmark]

3 minutes ago, Maestrobjwa said:

Recency bias fron 2022-23? Lol But that seemed extreme even by nina standards.

That season had a huge SSW that would have produced for the coast had the immense RNA been slightly less anomalous....so while it didn't work out, it isn't like it was March 1998. That season is a great example of why the +QBO/La Nina couplet doesn't necessarily mean an automatic strong PV from start to finish.

[brooklynwx99]

1 minute ago, 40/70 Benchmark said:

That season had a huge SSW that would have produced for the coast had the immense RNA been slightly less anomalous....so while it didn't work out, it isn't like it was March 1998.

Dec 2022 also got screwed by a TPV lobe phasing with a vicious shortwave over the Rockies. that thing escapes and dives south and you get a blizzard

we have gotten no breaks whatsoever. unfortunately, luck plays a large part in snowfall and we can't really quantify that. it's going to be that way unless we become infinitely precise, which will never happen

[40/70 Benchmark]

13 minutes ago, brooklynwx99 said:

Dec 2022 also got screwed by a TPV lobe phasing with a vicious shortwave over the Rockies. that thing escapes and dives south and you get a blizzard

we have gotten no breaks whatsoever. unfortunately, luck plays a large part in snowfall and we can't really quantify that. it's going to be that way unless we become infinitely precise, which will never happen

Yes, I was focusing on the second half of the season, but that is absolutely true.

[PhiEaglesfan712]

The fact that there were -2 to -4 temp departures for most places in the East in May and June 2023 will always make me believe that 2022-23 had the potential for cold and snow. We haven't got extended cold during that part of the season since June/July 2009.

What makes the cold of May and June 2023 even more odd is that there was no cold/snowy winter to precede or succeed it (like the summer of 2009 cold was in between the cold and snowy winters of 2008-09 and 2009-10).

[bluewave]

20 minutes ago, brooklynwx99 said:

we have gotten no breaks whatsoever. unfortunately, luck plays a large part in snowfall and we can't really quantify that. it's going to be that way unless we become infinitely precise, which will never happen

I understand the sentiment when we use terms like luck when dealing with weather patterns. I even used the term the other day when I stated that we got lucky when the MJO went into phase 8 during January 22. But there are mechanisms driving the weather patterns with reasons behind our sensible weather outcomes.

From 2010 to 2018 we were in a fantastic pattern for snow along the East Coast. It came down to the Pacific Jet not being overpowering allowing frequent Benchmark storm tracks. There was no shortage of record warmth in snowy winters like 12-13, 15-16, 16-17, and 17-18. But we were able to get cold and snowy storm tracks in warm patterns.

Something changed with the Pacific Jet during the 18-19 winter. We started to get stretches when it became overpowering with primary low tracks through the Great Lakes and hugging the East Coast. So we started to see that even during cold patterns the storms were taking warmer tracks for the East Coast. 

Fast forward to this December and we have been seeing a similar pattern. Great snowfall outcomes for the lake effect zones and much less along the East Coast. Same old pattern of cold arriving after the storms and not being place ahead of the storms. When we are able to get some development near the Benchmark, there is often a low in the lakes forcing the baroclinic zone too far north. So this month so far is featuring a series of ridges and troughs crossing the country with alternating warm ups and cool downs. But the faster Pacific Jet is the underlying pattern leading to less snow along the East Coast even with the windows of cold we have been getting. So we don’t need a sustained much warmer than average pattern for below normal snows. 

if we take a look at the Pacific Jet anomalies since 2010, there has been an increase since the 18-19 winter. Plus we just saw the models greatly underestimate the Pacific Jet the closer in time we got to the forecast period last few days. December 2022 had one of the greatest December -AO blocks on record with well below normal snowfall. Many places even had a small cold departure for the month. 
 

[40/70 Benchmark]

1 hour ago, bluewave said:

I understand the sentiment when we use terms like luck when dealing with weather patterns. I even used the term the other day when I stated that we got lucky when the MJO went into phase 8 during January 22. But there are mechanisms driving the weather patterns with reasons behind our sensible weather outcomes.

From 2010 to 2018 we were in a fantastic pattern for snow along the East Coast. It came down to the Pacific Jet not being overpowering allowing frequent Benchmark storm tracks. There was no shortage of record warmth in snowy winters like 12-13, 15-16, 16-17, and 17-18. But we were able to get cold and snowy storm tracks in warm patterns.

Something changed with the Pacific Jet during the 18-19 winter. We started to get stretches when it became overpowering with primary low tracks through the Great Lakes and hugging the East Coast. So we started to see that even during cold patterns the storms were taking warmer tracks for the East Coast. 

Fast forward to this December and we have been seeing a similar pattern. Great snowfall outcomes for the lake effect zones and much less along the East Coast. Same old pattern of cold arriving after the storms and not being place ahead of the storms. When we are able to get some development near the Benchmark, there is often a low in the lakes forcing the baroclinic zone too far north. So this month so far is featuring a series of ridges and troughs crossing the country with alternating warm ups and cool downs. But the faster Pacific Jet is the underlying pattern leading to less snow along the East Coast even with the windows of cold we have been getting. So we don’t need a sustained much warmer than average pattern for below normal snows. 

if we take a look at the Pacific Jet anomalies since 2010, there has been an increase since the 18-19 winter. Plus we just saw the models greatly underestimate the Pacific Jet the closer in time we got to the forecast period last few days. December 2022 had one of the greatest December -AO blocks on record with well below normal snowfall. Many places even had a small cold departure for the month. 
 

No one is denying that, but in a more stochastic sense, it still does come down to luck at the end of the day....its just that in a more hostile regime, the deck is more stacked against you. You still need to draw a favorable hand, regardless....which is possible in a bad pattern, especially in SNE. NYC is tougher to score in bad pattern, I agree.

[snowman19]

2 hours ago, 40/70 Benchmark said:

No one is denying that, but in a more stochastic sense, it still does come down to luck at the end of the day....its just that in a more hostile regime, the deck is more stacked against you. You still need to draw a favorable hand, regardless....which is possible in a bad pattern, especially in SNE. NYC is tougher to score in bad pattern, I agree.

I mean bottom line, the background state is still the same and it’s not showing any signs of some unexpected, massive shift. We can count every pixel on the SSTA maps at this point and it’s not going to make any difference. Fact is, the PDO is still very strongly negative and the WPAC warm pool in MJO 4-6 is still there. It’s showing transient cooling due to the very strong convection firing, but the SSTs there are still a furnace and they extend deep below the surface. Once the convection lightens up, they will warm at the surface anew. IMO we are grasping at straws at this point. That said, I do think we see a big PAC regime (PDO, IO, WPAC warm pool, ENSO) shift but it’s not going to happen between today and March 30th. That’s going to be a driving feature of next winter….

[40/70 Benchmark]

Just now, snowman19 said:

I mean bottom line, the background state is still the same and it’s not showing any signs of some unexpected, massive shift. We can count every pixel on the SSTA maps at this point and it’s not going to make any difference. Fact is, the PDO is still very strongly negative and the WPAC warm pool in MJO 4-6 is still there. It’s showing transient cooling due to the very strong convection firing, but the SSTs there are still a furnace and they extend deep below the surface. Once the convection lightens up, they will warm at the surface anew. IMO we are grasping at straws at this point. That said, I do think we see a big PAC regime (PDO, IO, WPAC warm pool, ENSO) shift but it’s not going to happen between today and March 30th. That’s going to be a driving feature of next winter….

No we aren't...not if you aren't looking for a 2010-2011 redux. However, most of us understand that and are simply looking for a mismatch period, which I happen to think is a good bet next month.

[snowman19]

I understand the sentiment when we use terms like luck when dealing with weather patterns. I even used the term the other day when I stated that we got lucky when the MJO went into phase 8 during January 22. But there are mechanisms driving the weather patterns with reasons behind our sensible weather outcomes.
From 2010 to 2018 we were in a fantastic pattern for snow along the East Coast. It came down to the Pacific Jet not being overpowering allowing frequent Benchmark storm tracks. There was no shortage of record warmth in snowy winters like 12-13, 15-16, 16-17, and 17-18. But we were able to get cold and snowy storm tracks in warm patterns.
Something changed with the Pacific Jet during the 18-19 winter. We started to get stretches when it became overpowering with primary low tracks through the Great Lakes and hugging the East Coast. So we started to see that even during cold patterns the storms were taking warmer tracks for the East Coast. 
Fast forward to this December and we have been seeing a similar pattern. Great snowfall outcomes for the lake effect zones and much less along the East Coast. Same old pattern of cold arriving after the storms and not being place ahead of the storms. When we are able to get some development near the Benchmark, there is often a low in the lakes forcing the baroclinic zone too far north. So this month so far is featuring a series of ridges and troughs crossing the country with alternating warm ups and cool downs. But the faster Pacific Jet is the underlying pattern leading to less snow along the East Coast even with the windows of cold we have been getting. So we don’t need a sustained much warmer than average pattern for below normal snows. 
if we take a look at the Pacific Jet anomalies since 2010, there has been an increase since the 18-19 winter. Plus we just saw the models greatly underestimate the Pacific Jet the closer in time we got to the forecast period last few days. December 2022 had one of the greatest December -AO blocks on record with well below normal snowfall. Many places even had a small cold departure for the month. 
 

Yet another example of the SE ridge/WAR getting badly underestimated by the models until we get closer in time. Different winter, same story. The Atlantic has not changed one iota (+AMO). Maybe we see some sort of regime shift there too come spring and summer like I think may happen in the PAC

[PhiEaglesfan712]

2 minutes ago, snowman19 said:

Yet another example of the SE ridge/WAR getting badly underestimated by the models until we get closer in time. Different winter, same story. The Atlantic has not changed one iota (+AMO). Maybe we see some sort of regime shift there too come spring and summer like I think may happen in the PAC

 

 

 

 

The big difference, though, from the several previous winters is that we actually have a December that opened cold. That hasn't happened since 2017. While that doesn't guarantee anything (we could still get something like 2007-08), at least I can be optimistic that the winter isn't going to be cooked like 2019-20 or the last few years.

Yeah, I'm not looking for a 2010-11 type season to happen, but a 2005-06 redux is certainly doable.

[snowman19]

3 minutes ago, PhiEaglesfan712 said:

The big difference, though, from the several previous winters is that we actually have a December that opened cold. That hasn't happened since 2017. While that doesn't guarantee anything (we could still get something like 2007-08), at least I can be optimistic that the winter isn't going to be cooked like 2019-20 or the last few years.

Yeah, I'm not looking for a 2010-11 type season to happen, but a 2005-06 redux is certainly doable.

It hasn’t been that long. December, 2022 was cold

[GaWx]

 1st 1/6 of E US met winter winner (projecting ahead to 12/15): cold

 We’ll see how the other 5/6 plays out. Hope we get another cold 1/6 at some point. Doesn’t seem like far fetched possibility, especially since there’s some tendency for cold in Dec to repeat in a portion of Jan and/or Feb. (more in Jan than Feb from what I recall, especially in La Niña).

[jm1220]

40 minutes ago, PhiEaglesfan712 said:

The big difference, though, from the several previous winters is that we actually have a December that opened cold. That hasn't happened since 2017. While that doesn't guarantee anything (we could still get something like 2007-08), at least I can be optimistic that the winter isn't going to be cooked like 2019-20 or the last few years.

Yeah, I'm not looking for a 2010-11 type season to happen, but a 2005-06 redux is certainly doable.

I’m hoping for a 7-10 day period where we can get something to happen like early in Feb when we had enough of a window for the 6-8” snowstorm I had. I highly doubt there’ll be a sustained favorable period with cold and a good storm track this winter, the Pacific jet will demolish anything that tries to set up. I’m counting on luck where I’m living. Of course in this Nina pattern we’ll probably get the SWFE train sooner or later where I-90 and north will rack up win after win while I get maybe a few sleet pellets before rain. 

[Maestrobjwa]

1 hour ago, snowman19 said:

It hasn’t been that long. December, 2022 was cold

That December didn't still average warm? I seem to remember just that one arctic Christmad weekend then warm again...

[PhiEaglesfan712]

6 minutes ago, Maestrobjwa said:

That December didn't still average warm? I seem to remember just that one arctic Christmad weekend then warm again...

It was close to average. On par with years like 2007 and 2016. It certainly wasn't several degrees below average like 2005 or 2010.

[jconsor]

MJO phases 5 and 6 are far from a guarantee of warmth in the eastern US.

https://x.com/commoditywx/status/1866191470287286392

https://x.com/bamwxcom/status/1866093279948763384

 

 

[Allsnow]

 

[Allsnow]

 

[Snowstorms]

9 hours ago, roardog said:

There’s actually been a lot of cooling globally for whatever reason. The global anomalies are the lowest they’ve been in a long time. 

Maybe the La Nina is finally doing what it would in the past. Cool the oceans and planet. 

[bluewave]

While the forecasts beyond 2 weeks don’t have that much skill, both the EPS and GEFS are trying to show a more Nino-like WWB pattern by early January.

[so_whats_happening]

It is nice to see cooling finally starting to spread through the Equatorial Pacific, especially past the dateline which has struggled for the past few years to do. This should inhibit strong convection in the 6/7 region as the wave passes through so less overall impact from these phases going forward. The MJO is just crawling at this point so the initial thoughts of 5/6 by mid December seemed right but not sure we make it into 7 or 8 until January now. This is by far the strongest the Nina has looked this year and maybe just maybe there is a chance of hitting a trimonthly of -.5, monthly seems like the better option. The subsurface is a struggling and this last little push we are seeing could be the end of whatever Nina state we currently have. No rapid changes are expected but we look pretty close to 'peak' and should slowly neutralize out again.

The warming of waters in the Bering Sea, Sea of Okhotsk, and starting to show in the Gulf of Alaska are good things to help us down the road. While it does look like we did make a dent in the PDO numbers we are still running on the high side of things which is unfortunate, but it is nice to see the loop currents off of Japan instead of it being one solid orange/red/brown area.

[so_whats_happening]

The last 3 months of 500mb patterns shows we finally have changed up the persistent ridging just east of Japan, for now at least. It has not yet setup the continual western ridge like we saw in 13/14 but everything else was still pretty spot on. Again it is not to say that there will be redux of exactly what happened in 13/14 but it is interesting to note the similarities that have shown up over the past couple of months.

[donsutherland1]

On ERA-5, global Temperature Anomalies are currently the second highest for 12/7 (most recent data for 2024). They are well above the 3rd highest value for this time of year.

[roardog]

24 minutes ago, donsutherland1 said:

On ERA-5, global Temperature Anomalies are currently the second highest for 12/7 (most recent data for 2024). They are well above the 3rd highest value for this time of year.

The earlier discussion was about sea surface anomalies. Coral reef, OISST, CDAS are all at the lowest they have been in a long time. 

[donsutherland1]

12 minutes ago, roardog said:

The earlier discussion was about sea surface anomalies. Coral reef, OISST, CDAS are all at the lowest they have been in a long time. 

Thanks. Yes, that’s true.

[40/70 Benchmark]

7 hours ago, Allsnow said:

 

 

5 hours ago, bluewave said:

While the forecasts beyond 2 weeks don’t have that much skill, both the EPS and GEFS are trying to show a more Nino-like WWB pattern by early January.

Great example of why the only bias these guys have is a "correct" bias...call 'em as they see 'em. The warmth bias crap is really frustration over the past several winters being projected onto them. Ball busting is one thing, but the I suspect some are serious with that crap.

[GaWx]

 During cold ENSO: I found 21 cases of a cold dominated Dec. 1-15 in the E US (including SE) back to 1874 (like 2024 may turn out):

 2010, 2007, 2005, 2000, 1995, 1962, 1955, 1954, 1949, 1944, 1942, 1934, 1917, 1915, 1910, 1903, 1898, 1893, 1886, 1882, and 1875. So, 21 of ~70 cold ENSO Decembers.

 Of these 21 cold Dec. 1-15:

-These were cold 1st half Jan: 2011, 2001, 1996, 1945, 1943 (NE only), 1918, 1904, 1887, and 1883. So, 9 of 21 NE and 8 of 21 SE.

-These were cold 2nd half of Jan: 2011, 1963, 1956, 1955, 1945 (NE only), 1935, 1923, 1918, and 1904. So, 9 of 21 NE and 8 of 21 SE.

-These were cold 1st half of Feb: 2011 (SE only), 1996, 1963, 1955, 1945, 1934, 1918, 1916 (NE only), 1904, and 1899. So, 9 of 21 NE/SE.

-These were cold 2nd half of Feb: 2006 (NE only), 1963, 1950, 1916, 1904, 1894, and 1876 (NE only). So, 7 of 21 NE and 5 of 21 SE.

 - Only 2 of 21 had no return of enough cold to dominate half of a month in the NE in Jan or Feb: 2008 and 1911. So, this suggests 90% chance of at least another 1/2 month of cold domination in NE within Jan/Feb.

- Only 5 of 21 had no return of enough cold to dominate half of a month in the SE in Jan or Feb: 2008, 2006, 1943, 1911, and 1876. So, this suggests 76% chance of at least another 1/2 month of cold domination in SE within Jan/Feb.

- So, I’m expecting at least one 1/2 month of cold domination in the NE US and very likely also one in the SE within Jan/Feb. The lowest chance would be for this to be in the 2nd half of Feb.

- 7 of 21 had at least two 1/2 months of cold dominating in both the NE and SE within Jan/Feb. And 8 of 21 had at least two in the NE. Thus, though unlikely, there’s a halfway decent chance for two cold dominated 1/2 months in Jan/Feb (a little moreso in NE).

- 3 of 21 had at least three 1/2 months of cold dominating in both the NE and SE within Jan/Feb: 1963, 1918, and 1904. (Also, 1945 had three in just the NE while 2011 had three in just the SE. So, each region had 4 of 21 with three or more.) Thus, this is very unlikely.

- 1 of 21 had cold dominating all four halves of Jan and Feb in both the NE and SE: 1904. Thus this is extremely unlikely.

- Keep in mind that a half month not being cold could still be near normal as opposed to mild.

- I plan to bump this post by the end of Feb.

[Stormchaserchuck1]

I'd rather not have a big +PNA in December. Temps minus precip makes it a negative correlation in the Northeast. 

We had the same thing last December, then when the temp correlation goes from -0.1 (+10%) in Dec to -0.5 (+50%) in January, on Jan 1st last year, it switched to -PNA lol