2024-2025 La Nina

[GaWx]

New Euro Weeklies:

1. This week (12/2-8) coldest yet: just 6 days ago was mainly slightly AN

 

2. Following week (12/9-15) coldest yet: 4 days ago was mild

 

3. Week of 12/16-22 coldest yet (NN)

[bluewave]

7 hours ago, GaWx said:

Will last 1/2 of Dec eventually cool off, too, or is this cold period going to end up being just in 1st half of Dec? Any educated guesses?

Chances are we see a moderation of the pattern by mid to late December since we haven’t had a cold start to finish December with every week colder than average since 2010 around NYC.

[PhiEaglesfan712]

5 hours ago, bluewave said:

Chances are we see a moderation of the pattern by mid to late December since we haven’t had a cold start to finish December with every week colder than average since 2010 around NYC.

December 2017 was cold too, and that carried over into the start of January 2018. That one didn't really moderate until mid-January. Of course, we know about the absolute torch of February 2018, which skewed the winter into above average temperatures.

That said, I don't see this winter ending up like 2010-11 or 2017-18. I think a 2020-21 type winter is more likely.

[Stormchaserchuck1]

0z GFS holds +PNA pattern through Day 16, Dec 10. This is backing away from the transition I thought it would be showing now in the long range a few days ago. Pretty much, for the last 8 years after 15 days of a cold pattern we are about 0/20 in holding that pattern, but for now it looks to be holding. 

[mitchnick]

21 minutes ago, Stormchaserchuck1 said:

0z GFS holds +PNA pattern through Day 16, Dec 10. This is backing away from the transition I thought it would be showing now in the long range a few days ago. Pretty much, for the last 8 years after 15 days of a cold pattern we are about 0/20 in holding that pattern, but for now it looks to be holding. 

Incredible how we could go into what was thought to be a slam, dunk furnace only to be quite the opposite. This is how wx weenies are made/proliferate. Lol

[bluewave]

3 hours ago, Stormchaserchuck1 said:

0z GFS holds +PNA pattern through Day 16, Dec 10. This is backing away from the transition I thought it would be showing now in the long range a few days ago. Pretty much, for the last 8 years after 15 days of a cold pattern we are about 0/20 in holding that pattern, but for now it looks to be holding. 

This is going to be a warmer -EPO +PNA early December pattern than we have seen with similar teleconnections in the past. It was the warmest fall on record for many so the source regions will take time to cool. You can see the teleconnections can generate cold at 850mb but the surface departures aren’t forecast to be as cold. We would need to sustain this pattern deeper into the winter for the surface departures to catch up.

 

 

[mitchnick]

42 minutes ago, bluewave said:

This is going to be a warmer -EPO +PNA early December pattern than we have seen with similar teleconnections in the past. It was the warmest fall on record for many so the source regions will take time to cool. You can see the teleconnections can generate cold at 850mb but the surface departures aren’t forecast to be as cold. We would need to sustain this pattern deeper into the winter for the surface departures to catch up.

 

 

All ensembles say it (BN tems in the east) lasts in varying degrees starting in 72 hours for the duration of the ensemble runs. That should do the trick, if not sooner.

 

[mitchnick]

Just now, bluewave said:

BN for sure but not as cold as some of the past colder 500mb matches when Detroit got down near 0° the first week of December and NYC near 10°.

 

I'll be blunt...what's your point other than to nitpick, or is it just an agenda issue ingrained in you? Because I can't see any other options. We have a pattern that not only goes against every lr forecast, but makes everyone who acted as if they know it all look really stupid, and you make another post trying to belittle the cold. Why do it and what's the point?

And yes, this pattern will end at some point. So what? That won't minimize the undeniable error of those with forecasts, musings, hunches, discussions that never had this pattern on their radar...which is everyone!

[snowman19]

5 minutes ago, mitchnick said:

I'll be blunt...what's your point other than to nitpick, or is it just an agenda issue ingrained in you? Because I can't see any other options. We have a pattern that not only goes against every lr forecast, but makes everyone who acted as if they know it all look really stupid, and you make another post trying to belittle the cold. Why do it and what's the point?

And yes, this pattern will end at some point. So what? That won't minimize the undeniable error of those with forecasts, musings, hunches, discussions that never had this pattern on their radar...which is everyone!

Let’s be honest, this winter will be judged on how much snow it produces. 99% of winter lovers base a winter being great or a fail on how much snow it produces. Even if this winter turns out to be -5F from Dec-Mar, if it ends up dry with below average snowfall, people will call it a huge fail and say the winter sucked. Great winters are remembered for snow not cold

[bluewave]

16 minutes ago, mitchnick said:

I'll be blunt...what's your point other than to nitpick, or is it just an agenda issue ingrained in you? Because I can't see any other options. We have a pattern that not only goes against every lr forecast, but makes everyone who acted as if they know it all look really stupid, and you make another post trying to belittle the cold. Why do it and what's the point?

And yes, this pattern will end at some point. So what? That won't minimize the undeniable error of those with forecasts, musings, hunches, discussions that never had this pattern on their radar...which is everyone!

First, the seasonal long range model forecasts for December issued back in early November or even October have seldom been correct which everybody knows. Second, I was mentioning back in October that the early MJO indicator was indicating the potential for a mismatch in December like we saw in 2020, 2017, and 2010. I also stated that we would need to wait until we got closer to December in order to see if it would work out. So this is not a complete surprise. Third, I have no idea what you mean with a term like agenda since I never met a thermometer that had one. Finally, all my posts and forecasting techniques are big data driven where perspective is key. If perspective to past patterns are an issue for you maybe you need to look within and see where the resistance lies.

[mitchnick]

1 minute ago, bluewave said:

First of all the seasonal long range model forecasts for December issued back in early November or even October have seldom been correct which everybody knows. Second I was mentioning back in October the early MJO indicator was indicating the potential for a mismatch in December like we saw back in 2020, 2017, and 2010. I also mentioned that we would need to wait until we got closer to December in order for them to work out. Third I have no idea what you mean with a term like agenda since I never met a thermometer that had one. Finally, all my posts and forecasting techniques are big data driven where perspective is key. If perspective to past patterns are an issue for you maybe you need to look within and see where the resistance lies.

You have made 2 posts trying to minimize cold during a future period of time that obviously, hasn't occurred.  That's an agenda whether you realize it or not. There is no way possible to know in advance the "future progged" pattern will ever be close enough to those years listed on that composite to compare them fairly until the forecasted period occurs. Yet, you use that list like it's 11 days from now. And for what? Convince yourself or others it won't be as cold as years past? Like I said, sounds like an agenda to me whether you want to admit to yourself or not. 

Why don't you just let it play out and then analyze the numbers. Maybe you'll be right or maybe you'll be wrong, but you won't have anyone to question your reasons.

[MJO812]

6 minutes ago, mitchnick said:

You have made 2 posts trying to minimize cold during a future period of time that obviously, hasn't occurred.  That's an agenda whether you realize it or not. There is no way possible to know in advance the "future progged" pattern will ever be close enough to those years listed on that composite to compare them fairly until the forecasted period occurs. Yet, you use that list like it's 11 days from now. And for what? Convince yourself or others it won't be as cold as years past? Like I said, sounds like an agenda to me whether you want to admit to yourself or not. 

Why don't you just let it play out and then analyze the numbers. Maybe you'll be right or maybe you'll be wrong, but you won't have anyone to question your reasons.

The cold looks real on all the models.  We have a negative WPO which we haven't in years. 

It's also moving up in time after the Thanksgivjg wave. Alot of forecasts had a warm December . Can it warm up in the 2nd half ? Sure but the month will start out pretty cold in many places.

[jbenedet]

I get what @bluewaveis saying to a large degree, at least what it means for the northeast US. 

The bulk of the cold is dumping into the southeast US from the mountain west…The northeast will be seeing winds out of the west/wsw, and thousands of miles of mid latitude travel for the arctic airmass to moderate…Yes the overall atmosphere will be BN (cold) but this is not a situation that maximizes the surface cold potential in the densely populated areas of the northeast; quite the opposite when soil temps and SST’s are warm and snowpack to the west and north will be well below normal. 

For example, I believe DC has a much colder stretch relative to norms than Boston, incoming... Boston and Portland ME could end up pretty close to normal during this stretch.

[bluewave]

16 minutes ago, mitchnick said:

You have made 2 posts trying to minimize cold during a future period of time that obviously, hasn't occurred.  That's an agenda whether you realize it or not. There is no way possible to know in advance the "future progged" pattern will ever be close enough to those years listed on that composite to compare them fairly until the forecasted period occurs. Yet, you use that list like it's 11 days from now. And for what? Convince yourself or others it won't be as cold as years past? Like I said, sounds like an agenda to me whether you want to admit to yourself or not. 

Why don't you just let it play out and then analyze the numbers. Maybe you'll be right or maybe you'll be wrong, but you won't have anyone to question your reasons.

I am showing the model output which is forecasting a colder pattern for early December but not as cold as would be suggested by what has occurred with those teleconnections in the past. You keep bringing up the term agenda for some reason. If I have an agenda at all it’s trying to figure out the actual pattern. If that triggers you in some way look within yourself. 

[roardog]

I’ve noticed that 2M temps anomalies are usually too warm on the models already by day 10 or so. Just look at the euro weeklies. By the time you get to week three they usually show no below normal 2M temps anywhere in the world. lol. I think we should see what verifies first. Detroit will have no shot to reach 2002 level cold due to the Great Lakes but I think Chicago or Indianapolis has a shot to get some real mid winter type cold. 

[mitchnick]

26 minutes ago, bluewave said:

I am showing the model output which is forecasting a colder pattern for early December but not as cold as would be suggested by what has occurred with those teleconnections in the past. You keep bringing up the term agenda for some reason. If I have an agenda at all it’s trying to figure out the actual pattern. If that triggers you in some way look within yourself. 

Lol...like I said, ingrained. 

 

[bluewave]

36 minutes ago, jbenedet said:

I get what @bluewaveis saying to a large degree, at least what it means for the northeast US. 

The bulk of the cold is dumping into the southeast US from the mountain west…The northeast will be seeing winds out of the west/wsw, and thousands of miles of mid latitude travel for the arctic airmass to moderate…Yes the overall atmosphere will be BN (cold) but this is not a situation that maximizes the surface cold potential in the densely populated areas of the northeast; quite the opposite when soil temps and SST’s are warm and snowpack to the west and north will be well below normal. 

For example, I believe DC has a much colder stretch relative to norms than Boston, incoming... Boston and Portland ME could end up pretty close to normal during this stretch.

We will need to extended this pattern into mid to late December to get any noteworthy cold vs past events around NYC with how warm the Lakes and Eastern Canada are starting out.

 

 

[Terpeast]

26 minutes ago, mitchnick said:

Lol...like I said, ingrained. 

 

I’m with bluewave on this one. After watching the entire NA continent experience its warmest fall in ages, on top of the warmest winter on record last year, we’re not gonna have much snow cover to start with. Soil temps are going to be warm. 

The positive takeaway from this is that a cold pattern is taking place early on, allowing time for more snow cover to get laid down over Canada and central US, which will help produce more local sources of cold air, which will only help the East through the rest of the winter. I’m just hoping we don’t get another 89-90 scenario where December gets cold, and then it completely flips warm and stays that way through Jan-Feb. I think there will be more variability than that.

 

[FPizz]

41 minutes ago, mitchnick said:

Lol...like I said, ingrained. 

 

It can be -10 in Morristown NJ, but we'll get a post on how in 1925 it would have been -13, while at the same Newark NJ is 45 and why that is right and their temps are perfect.

[roardog]

I guess if we are talking about the NE part of the country then I agree there won’t be any “extreme” cold for now since the coldest of the air is routed to the south and west of there. International Falls, Lacrosse, etc are some cities that could have “ extreme” cold for late November/early December. It will take a little bit of time to fill eastern Canada with Arctic air after this mild pacific flow we’ve had this fall across North America. 

[PhiEaglesfan712]

19 minutes ago, FPizz said:

It can be -10 in Morristown NJ, but we'll get a post on how in 1925 it would have been -13, while at the same Newark NJ is 45 and why that is right and their temps are perfect.

Funny, NWS Mt. Holly posted about this in June: https://x.com/NWS_MountHolly/status/1797327260162396478

Weather still happens. Climate change is an average. The average temperature has gone up 2 degrees since then, so these readings from 1925 would likely be about 2 degrees higher if the same heat wave happened today. That would've meant five 100-degree days instead of just two.

https://x.com/NWS_MountHolly/status/1797424229769785685

2011 was the last time it passed 100 at Lehigh Valley International Airport. Despite that, the average temperature is still 2 degrees hotter than it was 99 years ago.

[bluewave]

42 minutes ago, FPizz said:

It can be -10 in Morristown NJ, but we'll get a post on how in 1925 it would have been -13, while at the same Newark NJ is 45 and why that is right and their temps are perfect.

Morristown won’t be getting anywhere near -10 in early December. They have warmed up quite a bit since 2002. That was the last time Morris County saw 0° cold first week of December. But as I said the -EPO +PNA this year won’t have the real Arctic cold to work in those areas first week of December coming off one of the warmest falls on record across North America.

Data for December 1, 2002 through December 7, 2002
Click column heading to sort ascending, click again to sort descending.

BOONTON 1 SE	COOP	15
CHATHAM 2 W	COOP	10
LONG VALLEY	COOP	0

 

[PhiEaglesfan712]

1 hour ago, Terpeast said:

I’m with bluewave on this one. After watching the entire NA continent experience its warmest fall in ages, on top of the warmest winter on record last year, we’re not gonna have much snow cover to start with. Soil temps are going to be warm. 

The positive takeaway from this is that a cold pattern is taking place early on, allowing time for more snow cover to get laid down over Canada and central US, which will help produce more local sources of cold air, which will only help the East through the rest of the winter. I’m just hoping we don’t get another 89-90 scenario where December gets cold, and then it completely flips warm and stays that way through Jan-Feb. I think there will be more variability than that.

 

I don't think we'll get a 89-90 scenario. November 1989 was cold, and it was already snowing by Thanksgiving. I think we'll more likely get another 2005-06 or maybe a 2020-21. Both were warm Novembers that turned cold at the beginning of December. Both years had a warm period in the middle of the winter, but reverted back to being colder and more snowy in February.

[Terpeast]

1 hour ago, PhiEaglesfan712 said:

I don't think we'll get a 89-90 scenario.

I don’t either, but to me that’s now the worst case scenario.

[donsutherland1]

Five  thoughts on the upcoming colder pattern triggered by a developing EPO block and forecast AO-/PNA+ pattern:

1. The first half of December looks cold in much of the East. A one-week period with a temperature anomaly of 6°-10° below normal is plausible.

2. Initially snowfall options could be limited due to the source region of the air masses.  It remains to be seen whether the recent rainfall in the East and the upcoming storm to the Great Lakes region later this week were exceptions rather than the beginning of the end of the ongoing drought in the Northeast. Until a persistently wetter pattern emerges, my operating assumption remains that the drought will persist. That raises the bar for big snowfall events even as cold should be sufficient to allow for opportunities through at least the first half of December. The Great Lakes region and LES belts should be in good shape. For snowfall, I'd rather be in such cities as Chicago, Detroit, Buffalo and Toronto than Philadelphia, New York City, or Boston.

3. In most cases following exceptional November warmth and a colder first half of December, the second half of the month was not much warmer than normal. 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.

4. The long-range guidance might rush the break in the colder pattern. I suspect that timing closer to the winter solstice than mid-month might be more realistic for the onset of any pattern change.

5. These developments do not necessarily mean that winter won't be warmer than normal as per the seasonal guidance (the seasonal guidance usually does better with three month assessments than month-to-month ones). They do reinforce the idea that the coming winter won't be as abnormally warm as the last two winters have been.

A potential wildcard remains ENSO. The probability of a full-fledged La Niña event (tri-monthly average) has decreased. A neutral-cold outcome remains possible. The relative ENSO Index (RONI) will be consistent with La Niña.

[jm1220]

46 minutes ago, bluewave said:

Great post. If NYC can finish December at or below 36.0° which would be -3.1 or lower, then my guess is that they will at least have shot at the first colder than average winter in 10 years. While this won’t be a guarantee, 5 out of 7 winters since 1991 with a December at or below 36.0° went on to a colder winter using our new warmer 91-20 climate normals. So the departures below are set to the 91-20 normals where the NYC December average is 39.1° and the winter average is 36.2°

https://www.weather.gov/media/okx/Climate/CentralPark/nycnormals.pdf

All Decembers since 1991 in NYC at or below 36° since 1991 and the DJF average temperature set to the 91-10 departures 

2000……31.1°……DJF departure using 91-10 normals..-2.7

1995…….32.2°….DJF….-4.0

2010…….32.8°…DJF…..-3.4

2017….….35.0°…DJF…...0.0

2005….…35.3°…DJF….+1.1

2009…….35.9°…DJF….-2.4

2002….…36.0°…DJF….-5.0

 

All of those winters were also snowier than average in NYC. I’m quite confident if we can get the cold in here for more than glancing few day shots, we can get the snow to follow. We haven’t gotten out of these longer lasting cold patterns without at least one decent snow event in the last 20 years, and whatever we get in December is a big bonus for winter as a whole especially in a Nina. In every snowy Nina in NYC we had at least one half decent December snow event. If we get a decent offshore storm track it can definitely be snow in NYC even in early December with cold enough source air. 

[bluewave]

7 minutes ago, jm1220 said:

All of those winters were also snowier than average in NYC. I’m quite confident if we can get the cold in here for more than glancing few day shots, we can get the snow to follow. We haven’t gotten out of these longer lasting cold patterns without at least one decent snow event in the last 20 years, and whatever we get in December is a big bonus for winter as a whole especially in a Nina. In every snowy Nina in NYC we had at least one half decent December snow event. If we get a decent offshore storm track it can definitely be snow in NYC even in early December with cold enough source air. 

It looks like the Great Lakes should open for business first.

[michsnowfreak]

8 hours ago, snowman19 said:

Let’s be honest, this winter will be judged on how much snow it produces. 99% of winter lovers base a winter being great or a fail on how much snow it produces. Even if this winter turns out to be -5F from Dec-Mar, if it ends up dry with below average snowfall, people will call it a huge fail and say the winter sucked. Great winters are remembered for snow not cold

If I judge a winter on just total snowfall and not all other factors like cold and snowfall, then I guess I really need to give a lot more credit to the post-2015 era and less credit to the fact it was mild.

[michsnowfreak]

6 hours ago, roardog said:

I’ve noticed that 2M temps anomalies are usually too warm on the models already by day 10 or so. Just look at the euro weeklies. By the time you get to week three they usually show no below normal 2M temps anywhere in the world. lol. I think we should see what verifies first. Detroit will have no shot to reach 2002 level cold due to the Great Lakes but I think Chicago or Indianapolis has a shot to get some real mid winter type cold. 

It's looking like a LES/Clipper pattern. As we know, clippers are probably THE most difficult pattern to forecast more than a handful of days out. Always run the risk of cold and dry but what an unexpected early start to good winter weather. 

[GaWx]

 Natural gas opened up a whopping 7% this evening! With the ensembles still looking cold dominated, with no end yet in sight, and with NG having closed close to 7% off its highs on Fri, that actually isn’t a shock. So, now it is back up to near its Thu evening highs in the 3.50s.