Fall 2025 WX Discussion Thread

[jaxjagman]

8 hours ago, fountainguy97 said:

Phew

Where is this,cool pic anyways?Looks so surreal,awesome

[fountainguy97]

1 minute ago, jaxjagman said:

Where is this,cool pic anyways?Looks so surreal,awesome

My house here in Erwin! 

[Carvers Gap]

All three 0z global ensembles show the transition to an EPO and/or PNA ridge by very late this month.  Operationals don't have it at 0z, but that could easily change.  Ensembles are the choice for now.  Hopefully, we see further runs over the next 2-3 days which sporadically show major cold out breaks at least heading SE out of Canada along with big highs.

[Carvers Gap]

The Euro Weeklies today use the first week as a transition week(as opposed to full blown cold) and repay us with cold the rest of the month.  I am seeing a bit of a trend to dump cold in the west and then it spreads eastward.  We have seen this trend on modeling(and it be correct) more times than I can count during the past decade.  The 12z GEPS absolutely slams the cold into the West and it quickly spreads eastward.  With all the bouncing around today, this may be a very wicked shot o cold air - lots of bouncing around with very cold air.  It is worth noting that the Canadian model suite will often "see" the extreme of cold air first.  While the Euro is sidestepping a bit, the GEFS and Canadian ensembles at 12z are quite cool.  Remember it is shoulder season and possibly VERY cold air in the mix for December....so no surprise today.  

[Daniel Boone]

1 hour ago, Carvers Gap said:

The Euro Weeklies today use the first week as a transition week(as opposed to full blown cold) and repay us with cold the rest of the month.  I am seeing a bit of a trend to dump cold in the west and then it spreads eastward.  We have seen this trend on modeling(and it be correct) more times than I can count during the past decade.  The 12z GEPS absolutely slams the cold into the West and it quickly spreads eastward.  With all the bouncing around today, this may be a very wicked shot o cold air - lots of bouncing around with very cold air.  It is worth noting that the Canadian model suite will often "see" the extreme of cold air first.  While the Euro is sidestepping a bit, the GEFS and Canadian ensembles at 12z are quite cool.  Remember it is shoulder season and possibly VERY cold air in the mix for December....so no surprise today.  

Probably factoring the MJO. Crawling through 6 and into 7 by early December. Transition in 7 makes sense if the MJO is ruling the Roost. Continued blocking has become a bit of a Question for December now as some Data has backed off some. 

[Carvers Gap]

19 hours ago, Daniel Boone said:

Probably factoring the MJO. Crawling through 6 and into 7 by early December. Transition in 7 makes sense if the MJO is ruling the Roost. Continued blocking has become a bit of a Question for December now as some Data has backed off some. 

I honestly don't use the MJO much in November and early December.  I wonder if modeling is over-emphasizing it.  Either way, a delay would probably allow for the cold to last into early January - good recipe!  

I will say that I track an "eastern" cold shot only to have it dump West...and then come eastward around Christmas.  It was delayed by about three weeks.  I need to check the thread, but that might be the Christmas Eve anafront year.

[Carvers Gap]

Just checked.  Nope, not December 2020.  Though this current projected cold looks remarkably similar in its progression.  

I am looking for the year where an epic December(way better than what weeklies have now) delayed by about three weeks.  It might be that late December/early January cold snap where it didn't snow much - 17 or 18'?  

I remember sitting in a movie theater and seeing the Weeklies flip warm.  I know...get a life right?  I had been banging the cold drum for weeks, and it was like someone turned the lights off!  LOL. Seems like it has been 7-10 years since that time.  

I can remember really two places where I connect weather models going nuts(good and bad) and a specific location.  The other one(besides the movie theater) is in Hampton.  We had been back in the boondocks with no cell service.  When we got to the hill overlooking Hampton, I got several texts from @tnweathernutw/ snowmaggedon maps that originally included us.  To this day, I hate missing a 12z suite because of that.  Those maps were flat out nuts.  DC got most of our snow, but the model runs for a few days were epic.

[Daniel Boone]

33 minutes ago, Carvers Gap said:

I honestly don't use the MJO much in November and early December.  I wonder if modeling is over-emphasizing it.  Either way, a delay would probably all for the cold to last into early January - good recipe!  

I will say that I track an "eastern" cold shot only to have it dump West...and then come eastward around Christmas.  It was delayed by about three weeks.  I need to check the thread, but that might be the Christmas Eve anafront year.

Yeah, hopefully they are overemphasizing it. Could also be the SSW starting to affect the Models. If so, some back and forth and wonky solutions to come as we know.

[Daniel Boone]

22 minutes ago, Carvers Gap said:

Just checked.  Nope, not December 2020.  Though this current projected cold looks remarkably similar in its progression.  

I am looking for the year where an epic December(way better than what weeklies have now) delayed by about three weeks.  It might be that late December/early January cold snap where it didn't snow much - 17 or 18'?  

I remember sitting in a movie theater and seeing the Weeklies flip warm.  I know...get a life right?  I had been banging the cold drum for weeks, and it was like someone turned the lights off!  LOL. Seems like it has been 7-10 years since that time.  

I can remember really two places where I connect weather models going nuts(good and bad) and a specific location.  The other one(besides the movie theater) is in Hampton.  We had been back in the boondocks with no cell service.  When we got to the hill overlooking Hampton, I got several texts from @tnweathernutw/ snowmaggedon maps that originally included us.  To this day, I hate missing a 12z suite because of that.  Those maps were flat out nuts.  DC got most of our snow, but the model runs for a few days were epic.

Think it was 17-18. Terrible waist of cold.

[Matthew70]

5 hours ago, Daniel Boone said:

Yeah, hopefully they are overemphasizing it. Could also be the SSW starting to affect the Models. If so, some back and forth and wonky solutions to come as we know.

I just read that a SSW is in motion. Is it right & is it good or bad?  We shall see.

[jaxjagman]

You have to have warming with the wind reversal to be a major SSWE,right now it just seems to be a minor,but thats to early to tell,Euro only shows the wind reversal lasting just a couple days.We'll find out soon enough,next week.

[Daniel Boone]

You beat me to it Jax. Lol. Yeah, looks minor but does appear to be one from what I've gathered. Either way, should keep the PV in a weak State for awhile. As you said, we'll know by next week for sure.

[jaxjagman]

Should have said we'll know more by next week.But some of social media especially on X make it sound like the apocalypse is coming.We're gonna fall -800C below normal,snow drifts as tall as the empire state building,we're all gonna die.Like there hasnt been a SSWE before.

[Carvers Gap]

The 0z GEPS and 6z(edit...) GEFS are frigid at the ends of their runs today.  The EPS is lagging as it kicked the can by about 3-5 days yesterday.  It still "should" get there, but have to be careful for the Charlie Brown football deal.  When ensembles get that cold, chances start to go way up.  Those ensembles are cold for about 75% o NA and almost all of the Lower 48.  Pretty impressive.

[nrgjeff]

Just today the CFS and GEFS weeklies join the colder forecast for December. ECMWF weekly had been consistent which added confidence even before others joined the chorus. 

Agree it will take about a week (2nd or 3rd front) to chip away at the SER that builds next week through early Thanksgiving week. CFS and extrapolating mid-range ensembles points to right after Thanksgiving. Same for some AI stuff. GEFS and ECMWF weeklies are slower more like 1 Dec.

While the MJO promotes the slower timing, a Strato warming event could promote the faster timing. SSW is normally the slower process but it's already in progress. MJO has to tee up the warmer phases first. 

Physical Science Lab Asia pressure and temps has not really set up yet, no surprise with the MJO. North America has a ways to go. Eastern Siberia shows very early signs. Rest of Russia and China no signal (bearish or bullish) so overall those charts are not set up yet.

PS @Carvers Gapyou'd prolly love this site given your post about pressure / temps on the winter spec. Maps won't load for me, so maybe you're already looking there. 

PSL Map Room: Global Circulation (Quick Menu): NOAA Physical Sciences Laboratory

[John1122]

I'd just as soon the cold arrive around/after December 7th, then hopefully give us 6 weeks into late January. 

[nrgjeff]

The SER can probably arrange that. I should be careful about what I joke. 
Edit: latest ensembles are slower.

Otherwise a bird in the hand sooner is always nice. If we get a Jan. thaw maybe February gives a winter encore. Kind of the Carvers Cossgrove hybrid winter.

While La Nina is notorious for west first SER, the hemispheric pattern variability should deliver bouts of cold to the Southeast too.

[Carvers Gap]

Whew.  Not often that I see an ensemble look that cold at range.  The 12z GEFS looks similar, but with lighter blues.  That is most of the continent.  384 map...so proceed with caution.

[John1122]

The end of the Euro is a big Alaska block and cold rapidly advancing eastward into our area from straight over the pole. It's not too dissimilar to the post Carvers made above of the GEPS but it is a bit warmer on the west coast with AN temps there.

[John1122]

The EPS has a similar set up, but much less extreme as is normal for ensembles vs OP runs, and the cold isn't quite to our area yet at the end.

[KakashiHatake2000]

next week looks quite rainy and wet pattern taking place

[Carvers Gap]

The EPS is on an island right now.  The Euro Weeklies, after being locked-in for weeks, have flipped to AN temps for week one of December and normal for week 2.  It is definitely "can kicking."  On the other hand, the GFS and Canadian ensembles and LR ext models have assumed the Euro Weeklies former "cold is king" spot.  Welcome to shoulder season modeling.  

The CFSv2 at lunch was just ridiculously cold w/ the ridge heights and trough lows.  We are talking subtropics to the NP.  That is not a stable pattern, and probably why we see differences.  But....that is a pattern which could deliver insanely cold air into the Lower 48.  The December which Boone referenced and 89 would be on the table as ensembles.  I "think" cold is coming, but going into battle with the Weeklies flipping doesn't give me great confidence.  

I often wonder if the Euro Weeklies are about 1-2 days ahead of other LR ext models w/ better data.  With the Weeklies trending away from a cold start to December, I would think other LR ext models will do the same during the next couple of days - if they are actually going to flip.  BTW, the 500 pattern isn't terrible on the Euro Weeklies, but it isn't cold either. 

The SSW....has screwed up more than one great cold snap during the past decade.  That event often wrecks havoc on modeling and can inflict damage on what looked like a promising even.

The SSW....most likely we are looking at modeling bouncing around due to low level cold air being underneath those 500 patterns.  Might as well drop a cat in a bathtub - cause all you know what is gonna break loose.  

Overall, I think cold is coming just after thanksgiving, but with a strong word of caution.  FWIW, I generally like the CMC when cold is in the forecast at medium and long range.  It often over-does the cold, but it actually "sees" it.

I would feel a bit better if the Euro and EPS hadn't been right about this last system, and "at range" to boot.  But the GEFS was sneaky good as well - just not the GFS.  The GEFS looks like a good compromise for the two weeks after Thanksgiving.