2024-2025 La Nina

[Terpeast]

52 minutes ago, donsutherland1 said:

It seems that it will turn colder for the start of January based on the latest guidance. But that doesn't mean that there necessarily will be the kind of historic outbreak of cold that BAMWX is calling for or the severe Arctic outbreak that Bastardi is mentioning for mid or late January. Even if a colder pattern seems likely, source regions will be critical, as will the degree of blocking to sustain it.

Personally I'm not rooting for a historic cold outbreak. I just want it cold enough to snow, even if only by a degree.

Subzero cold? I worry about my pipes.

 

[mitchnick]

7 minutes ago, GaWx said:

They look fairly similar to yest. No torch with lots of NN in E US (I’d take it). No big cold either. A couple of weeks are slightly cooler in the SE. Here’s the last 2 weeks fwiw:

Week 5:

 

Week 6:

Having the cold drapped across southern Canada is reassuring we have a close source of cold to tap unlike many previous years.

L

[mitchnick]

2 minutes ago, Terpeast said:

Personally I'm not rooting for a historic cold outbreak. I just want it cold enough to snow, even if only by a degree.

Subzero cold? I worry about my pipes.

 

Wait till' you get old. 

[MANDA]

6 minutes ago, Terpeast said:

Personally I'm not rooting for a historic cold outbreak. I just want it cold enough to snow, even if only by a degree.

Subzero cold? I worry about my pipes.

 

In addition to frozen pipes historic cold is often dry, granted historic cold can sometimes end with something big but that is the exception rather than the rule.   Modest cold with a good storm track will be a win around here.

[donsutherland1]

1 hour ago, michsnowfreak said:

I still don't think bamwx was meaning that map to verify literally. 

That map should not have been posted. Were it 1 to maybe 2 weeks out, then things would be different.

[donsutherland1]

40 minutes ago, Terpeast said:

Personally I'm not rooting for a historic cold outbreak. I just want it cold enough to snow, even if only by a degree.

Subzero cold? I worry about my pipes.

 

Cold enough for snow works for me.

[michsnowfreak]

1 hour ago, donsutherland1 said:

That map should not have been posted. Were it 1 to maybe 2 weeks out, then things would be different.

I don't disagree. Nor do I need -30° temp departures in Michigan in January lol. I'm a snowlover so anything around average is fine. We saw that kind of cold in 2014, 2015, and 2019. Fortunately each time we had good snowpack in place, but during the infamous arctic outbreaks of 1899 & 1934 we only had a half inch to 1 inch of snow on the ground while deep snow was in place at much further south locales.

[michsnowfreak]

2 hours ago, Terpeast said:

Personally I'm not rooting for a historic cold outbreak. I just want it cold enough to snow, even if only by a degree.

Subzero cold? I worry about my pipes.

 

In 2014 & 2015 it got so cold many people had frost on the inside of their window sill edges. In 2019 I remember the trees creaking like old doors and I did the toss boiling water in the air thing and saw it turn to steam. That kind of cold is interesting but definitely dangerous. 

[GaWx]

2 hours ago, mitchnick said:

Having the cold drapped across southern Canada is reassuring we have a close source of cold to tap unlike many previous years.

L

This lack of either a cold or warm signal in the E US probably would in reality mean one of the most likely scenarios being an about even mix of BN from Canadian highs and mild/Pacific in between to average out in the general vicinity of NN in a good portion of the area with a smaller chance of either cold or mild dominating the period over a good portion of the E US. NN overall often means most days are actually not NN but instead a mix.

[40/70 Benchmark]

https://easternmassweather.blogspot.com/2024/12/much-milder-balance-of-december-before.html

[GaWx]

 Fwiw, the extended 0Z 12/7 GEFS taken at face value suggests a shot at a winter storm for the Mid-Atlantic and slight chance for part of the SE as a Canadian high moves down and then E to the E coast with subtropical moisture shortly after overrunning it ~Jan 7. But since that would be a month away, which is way too far out to even be semi-predictable, that is all merely fun speculation and certainly not even close to a forecast!

[brooklynwx99]

7 hours ago, snowman19 said:

Complete nonsense on the major SSW. The SPV stays very strong. And BS on getting cold. Huge ++EPO developing, the EPO floodgates open wide and the entire CONUS and Canada get flooded with PAC air for weeks. Good luck getting cold and snowy

 

 

 

 

 

 

 

 

“flooded with Pacific air for weeks” is a bit dramatic, no?

also i thought Webb was an idiot lmao

[brooklynwx99]

14 hours ago, snowman19 said:

Complete nonsense on the major SSW. The SPV stays very strong. And BS on getting cold. Huge ++EPO developing, the EPO floodgates open wide and the entire CONUS and Canada get flooded with PAC air for weeks. Good luck getting cold and snowy. EDIT: @brooklynwx99 With your track record the last few years I’d tread very very lightly. And I only quoted Eric Webb because @MJO812 was making love to him last week

 

 

 

 

 

 

 

 

thanks for your concerns about my track record. my timbers have been shivered

[brooklynwx99]

On 8/28/2024 at 3:47 PM, brooklynwx99 said:

it would be hilarious if this winter ended up good for many people even though there were vibes and evidence to the contrary. I remember 20-21 was like that

for the record, I do not expect a good winter in the NE (especially outside of New England), but it would be funny... and definitely welcome

this has been my viewpoint on this winter pretty much the whole time. the 2013-14 stuff is cool and all but I have thought 21-22 would do a better job with the general flavor of the year

could have done better last year, but I made an educated guess based on atmospheric variables and it failed. it happens. better to take a stand and learn from it than to be wishy washy like you see all the time nowadays

[brooklynwx99]

also, and this may the case for some others, but I don't really feel the need to post about warm periods, because 1) they're horribly boring and 2) the same people will breathlessly post about them. why bother. so yes, it makes it seem like I have more of a cold bias than I actually do

it'll get quite warm for the next two weeks, but I don't really care to give it much more thought than that (at least when posting) because 98% of people couldn't care less and it's a bummer

[mitchnick]

21 minutes ago, brooklynwx99 said:

also, and this may the case for some others, but I don't really feel the need to post about warm periods, because 1) they're horribly boring and 2) the same people will breathlessly post about them. why bother. so yes, it makes it seem like I have more of a cold bias than I actually do

it'll get quite warm for the next two weeks, but I don't really care to give it much more thought than that (at least when posting) because 98% of people couldn't care less and it's a bummer

Not that I disagree with the 2 week warm period, but this trough/cold later this week is trending noticeably colder than just 2 days ago. Imby, it's looking colder than the cold this past week. But that will just be glossed over by most.

 

P.s. That's a cold run on the 6z Gfs fwiw

[bluewave]

The first week of December was the coldest back to 2010. But it was more of a short term cold pattern similar to recent years. The cold in early December 2010 extended right through January. It was a fantastic pattern for LES snows due to the block near Seattle and the record warmth in the Lakes. But those factors moderated the cold in the Northeast so the coldest relative to the means went to the south. These quick warm ups after cool downs have become the norm for the East. Our last extended cold month was January 22 in the East courtesy of the MJO 8 pattern. 
 

 

[PhiEaglesfan712]

58 minutes ago, bluewave said:

Our last extended cold month was January 22 in the East courtesy of the MJO 8 pattern. 

In winter. May and June 2023 were -2 to -4 temperature departure in many places in the East.

[bluewave]

9 minutes ago, PhiEaglesfan712 said:

In winter. May and June 2023 were -2 to -4 temperature departure in many places in the East.

It wast that cold around NYC with may averaging  -0.5 and June -1.1 against the warmest 30 year means on record.

[donsutherland1]

The cold start to December is on track, although readings in some places are milder than what had been shown on the guidance prior to the start of December. The first week of December saw temperatures in numerous locations in the East and Midwest average 6°-10° below normal.

Some updates on last week's thoughts.

1. A clipper system brought a trace of snow to Washington, DC, New York City, and Boston.

2. Following the clipper, a number of cities in the eastern third of the U.S. experienced their lowest temperatures so far this season including Chicago, Cleveland, Detroit, Indianapolis, Norfolk, and Richmond.

3. British Columbia experienced much above normal temperatures.

Five thoughts going forward:

1. A pattern change to milder weather still appears on track for mid-month. It will turn briefly very mild in the East on Tuesday and Wednesday, before another sharp cold shot brings much below normal temperatures for several days.

2. A storm will bring heavy rain to the Eastern Seaboard during late Tuesday into Thursday. An area running from Richmond to Boston could see widespread 1"-2" rainfall amounts with locally higher amounts of 3". Temperatures could surge to 60° or above in Washington, DC, Philadelphia, New York City, and perhaps Boston. Snowfall opportunities for the East Coast will remain limited through at least mid-month.

3. Minneapolis could see its first subzero low of the season on Thursday. Chicago and Milwaukee will likely experience their first single-digit temperatures of the season on Thursday. Detroit has a chance to drop below 10°.

4. After a short push of cooler air, Phoenix will see temperatures rebound into the 70s. Phoenix remains on track for a 78.3° annual mean temperature, which would surpass the existing mark of 77.3° from 2017 and 2020.

5. Overall, parts of the eastern third of the U.S. remain on course for a colder than normal December, even as the outcome of the closing week of the month remains uncertain (ECMWF weeklies are close to normal in the eastern half of the CONUS and Canada while the CFSv2 is warmer than normal across almost all of North America).

Long-Range:

There currently is a consensus among both long-range weekly tools that it could turn colder in early January (slower timing on the CFSv2). Supporting a faster arrival of colder air, the PNA is forecast to go positive around or just after mid-month. However, the EPO, NAO, and AO are forecast to remain largely neutral. That predominantly neutral state could persist into the start of January. The major fly in the ointment for the start of January is the risk that the PNA could go negative as shown on the 46-day EPS forecast. A PDO- supports a predominantly negative PNA. Were that outcome to verify, one could see the long-range guidance begin to shift the forecast area of cold westward as the late December period approaches.

Finally, there is some disagreement among the extended GEFS and ECMWF concerning the dominant pattern regime from late December into January. The GEFS favors an Alaskan Ridge during the first week of January, which would feature colder weather in the East and warmer weather in the West. The extended ECMWF is split between an Alaskan Ridge and Pacific Ridge into mid-January. A Pacific Ridge favors cold in the West and warmth in the East. 

Based on the current conflicting guidance, I suspect that the first week of January could see cold redevelop, possibly even during the last few days of December, but rather than locking in initially, the pattern could feature variability. Whether the cold pattern will lock in or yield to a milder one afterward remains to be seen.

[PhiEaglesfan712]

[bluewave]

You have to wonder what is going in with the WPO since we usually don’t see such dramatic reversals this time of year like the EPS, GEFS, and GEPS are showing. 
 

 

[GaWx]

14 minutes ago, PhiEaglesfan712 said:

These three are suggesting that the CFS’ forecast of going strong on the top of the diagram is likely out to lunch. That’s not surprising as the CFS has often had too strong an amplitude and isn’t at all reliable. Only the CMC agrees with the CFS.

[Terpeast]

25 minutes ago, GaWx said:

These three are suggesting that the CFS’ forecast of going strong on the top of the diagram is likely out to lunch. That’s not surprising as the CFS has often had too strong an amplitude and isn’t at all reliable. Only the CMC agrees with the CFS.

Previously the GEFS had it stronger going into 7, but now weaker lime the EPS?

[snowman19]

You have to wonder what is going in with the WPO since we usually don’t see such dramatic reversals this time of year like the EPS, GEFS, and GEPS are showing. 
 

 

The fact that even the -EPO happy long range EPS is seeing this speaks volumes. If that is in fact correct (Bering Sea trough/+WPO), it’s going to completely cutoff the arctic cross-polar flow and flood Canada and the lower 48 with PAC air. While not a “torch” it’s definitely mild verbatim

And as far as La Niña, we are seeing the importance of looking past the traditional ONI for atmospheric and oceanic clues. AGW has skewed everything so warm, that the traditional indicators for ENSO events are getting largely washed out

[snowman19]

37 minutes ago, GaWx said:

These three are suggesting that the CFS’ forecast of going strong on the top of the diagram is likely out to lunch. That’s not surprising as the CFS has often had too strong an amplitude and isn’t at all reliable. Only the CMC agrees with the CFS.

It would not surprise me one bit if the MJO signal dies before ever going 8-1-2, given the reasons I stated yesterday. I absolutely believe we see a repeating phase 4-5-6 reemergence this winter for those reasons 

[snowman19]

15 minutes ago, snowman19 said:

The fact that even the -EPO happy long range EPS is seeing this speaks volumes. If that is in fact correct (Bering Sea trough/+WPO), it’s going to completely cutoff the arctic cross-polar flow and flood Canada and the lower 48 with PAC air. While not a “torch” it’s definitely mild verbatim

And as far as La Niña, we are seeing the importance of looking past the traditional ONI for atmospheric and oceanic clues. AGW has skewed everything so warm, that the traditional indicators for ENSO events are getting largely washed out
 

@Bluewave @GaWx Here is a real good illustration of my point. The Niña standing wave is clear as day. The entire atmospheric and oceanic circulation is classic La Niña. Very good read here and why I seriously doubt the MJO signal ever makes it to or across the dateline:

 

 

 

 

[GaWx]

27 minutes ago, Terpeast said:

Previously the GEFS had it stronger going into 7, but now weaker lime the EPS?

I’m one who has for a long time preferred lower amp MJO (just outside, near, or inside circle) based on it being associated with colder in winter (especially Jan) than higher amp in the E US as well as being more favorable for major winter storms in the SE, especially ZR/IP in N GA, based on several decades worth of stats. However, I do wonder if that relationship still exists to the same extent due to the MC warm pool being so dominant the last 8 or so years.

[Terpeast]

1 minute ago, GaWx said:

I’m one who has for a long time preferred lower amp MJO (just outside, near, or inside circle) based on it being associated with colder in winter (especially Jan) than higher amp in the E US as well as being more favorable for major winter storms in the SE, especially ZR/IP in N GA. However, I do wonder if that relationship still exists due to the MC warm pool being so dominant the last 8 or so years.

I think for now the models might be latching into the warm pool bias due to persistency, but not sure it will stay that way forever (despite what snowman might be shouting from his rooftop). I think this winter will find a way to surprise us. 

[GaWx]

38 minutes ago, Terpeast said:

Previously the GEFS had it stronger going into 7, but now weaker lime the EPS?

Note that the spread of members’ amplitude on the GEFS’ MJO forecast is quite wide: