January 2026 Short/Medium Range Thread

[Carvers Gap]

The 12z GEM manages to keep its stuff together and that energy(which was headed from West Yellowstone to Hawaii on the 12z GFS) gets sent into the base of the trough south of Tenn.  I can't see the surface, but the 500 anomaly looks nice.

[Carvers Gap]

The 12z GEM at 500 has a lot of energy in it.  Never quite gets it together, but several small vortices rotate through.  That said, models are flirting with something big between Jan 15-20.  The GEM almost cuts off energy over the Gulf Coast during that time.  In fact at 192, it does cutoff a low over southern Alabama.

[Carvers Gap]

Honestly, before the 12z GFS lost its stuff...the GFS has a similar solution at 500 to the GEM.  The GEM wasn't far from the ICON.  Big piece of energy rotating through around 189.  The potential for a phase is increasing.  How that unfolds is still TBD, but man.

[Carvers Gap]

That trough has been on modeling around has been on modeling for a few days.  In fact, it was the image golf noted was not from the correct model run(I fixed that and thanks for the heads up).  Again, I used to just look at surface maps w/ pressure gradients on it.  That looks is good.  It may well not mature until it gets to the EC, but it is trying to go neutral over Alabama.  If it does, look out.

[Weatheriscool]

1 minute ago, Carvers Gap said:

That trough has been on modeling around has been on modeling for a few days.  In fact, it was the image golf noted was not from the correct model run(I fixed that and thanks for the heads up).  Again, I used to just look at surface maps w/ pressure gradients on it.  That looks is good.  It may well not mature until it gets to the EC, but it is trying to go neutral over Alabama.  If it does, look out.

Correct me if I am mistaken but if it can phase into a bigger storm it could pull down some really cold air in its wake. 

[Carvers Gap]

On the 12z GFS, that trough is negative tilt over Georgia.  The surface just wasn't there quite yet.  But give me that setup 10/10. Then the GFS loses it in the West.  The GEM and ICON had very similar setups.  The phase is not really a finesse deal.  It is just timing.  With that deep trough potentially in place, we are simply watching to see if the STJ can interact w/ the northern stream.  Pretty wild look on voracity maps.

[Bigbald]

1 minute ago, Carvers Gap said:

On the 12z GFS, that trough is negative tilt over Georgia.  The surface just wasn't there quite yet.  But give me that setup 10/10. Then the GFS loses it in the West.  The GEM and ICON had very similar setups.  The phase is not really a finesse deal.  It is just timing.  With that deep trough potentially in place, we are simply watching to see if the STJ can interact w/ the northern stream.  Pretty wild look on voracity maps.

When is the last time we had a negative tilt storm? It seems like its been forever.

[Matthew70]

The GFS has really become a last place model for many to look at.  I read somewhere that the I believe the AI Euro is dead on with its scores at 5 day or less. Correct me if I’m wrong.

[Carvers Gap]

1 minute ago, Weatheriscool said:

Correct me if I am mistaken but if it can phase into a bigger storm it could pull down some really cold air in its wake. 

Yes.  I am still sifting through the entire suite.  I don't see exceptional cold at this point, but seasonal looks likely during that time.  The second window(second ridge retrogression) for cold looks like it could be winter's worst.

This is why I am not overly sweating the MJO right now.  The "storm window" where we see a deep eastern trough w/ lots of energy and cold diving into it between Jan 15-20th...want to guess the MJO phase?  Six.

The CPC MJO models loop the MJO into 8 by the end of the month.  There is probably some lag(maybe a week) in that surface reflection here. But it makes sense that the MJO matches the next retrograding ridge cycle. If we can score in 6, roll a ridge east-to-west after that, and score phase 8 at the end of January or early Feb...that might be a really good rotation.  See GaWx's comments about phase 6.

Anyway, still plenty of uncertainty...but it the potential for an interesting few weeks of weather is increasing.  

[Weatheriscool]

1 minute ago, Carvers Gap said:

Yes.  I am still sifting through the entire suite.  I don't see exceptional cold at this point, but seasonal looks likely during that time.  The second window(second ridge retrogression) for cold looks like it could be winter's worst.

This is why I am not overly sweating the MJO right now.  The "storm window" where we see a deep eastern trough w/ lots of energy and cold diving into it between Jan 15-20th...want to guess the MJO phase?  Six.

The CPC MJO models loop the MJO into 8 by the end of the month.  There is probably some lag(maybe a week) in that surface reflection here. But it makes sense that the MJO matches the next retrograding ridge cycle. If we can score in 6, roll a ridge east-to-west after that, and score phase 8 at the end of January or early Feb...that might be a really good rotation.  See GaWx's comments about phase 6.

Anyway, still plenty of uncertainty...but it the potential for an interesting few weeks of weather is increasing.  

Guess we should enjoy the relative mild now, change is afoot 

[Carvers Gap]

4 minutes ago, Matthew70 said:

The GFS has really become a last place model for many to look at.  I read somewhere that the I believe the AI Euro is dead on with its scores at 5 day or less. Correct me if I’m wrong.

The GFS has been bad outside of day 5....really bad.  Just look at the 500 vort map today.  Crazy town.  However, it is usable inside of d5.  The agreement between the GFS, GEM, and ICON is a good thing.  How that potential phase unfolds is important. Just look at the 500 vort maps and you can see the interaction.

The good thing is that there may well be another window w/ the storm which follows the Jan15-16 storm.  

[Carvers Gap]

10 minutes ago, Bigbald said:

When is the last time we had a negative tilt storm? It seems like its been forever.

Been a while for E TN folks.  I am not sure that happens here.  To me, a strong neutral tilt trough is more likely around the 15th.  That could change, but the vortices appear "real" at this point.  The trough should be quite amplified.  It may well try to spin something up.  The amount of cold available is not a sure thing if it gets strung out.  If it maxes out, then we might be in business.  The wave after that doesn't look bad, and maybe the one after that even.

[Carvers Gap]

The 12z GFS, and it cannot be trusted w/ that run, has four winter events and/or storms within its full run.

[Carvers Gap]

11 minutes ago, Matthew70 said:

The GFS has really become a last place model for many to look at.  I read somewhere that the I believe the AI Euro is dead on with its scores at 5 day or less. Correct me if I’m wrong.

I don't know on that one. I generally prefer just the normal Euro deterministic at this time of year.  The Euro sometimes takes a little longer to trend.  I like watching the GEM, GEFS, and ICOn as sometimes their turning radius is a bit tighter to steal a car term.  The AIFS Euro is running now.  I carves out a pretty amplified trough...I just can't see what precedes that trough quite yet as the hours haven't filled back in on this run.

[Carvers Gap]

14 minutes ago, Matthew70 said:

The GFS has really become a last place model for many to look at.  I read somewhere that the I believe the AI Euro is dead on with its scores at 5 day or less. Correct me if I’m wrong.

Yes, it pops a low as well.  The AIFS version would likely be extended upslope over a large area...some mix or rain possible depending on time of day.  With the amplitude of that trough, the likelihood of something "spinning up" is higher than normal.

[Carvers Gap]

And I will certainly take what the 12z GEM is cooking up as well.  Lots of snow showers and cold between Jan 15-20th.  I "think" we end up seeing an organized system come out of this, but several days of over-running(not heavy) is possible.

[Holston_River_Rambler]

Nice slug of moisture incorporated into the Friday/ Saturday rain maker now:

WPC edging up precip forecast:

[housemtnTN]

Atlanta gets 8 inches of snow on this run and Myrtle Beach with 16 lol.

[John1122]

4 minutes ago, housemtnTN said:

Atlanta gets 8 inches of snow on this run and Myrtle Beach with 16 lol.

That's ice, their algorithm handles snow poorly. 

That said, it's a big winter storm East, South and West of us, so I wouldn't be shocked if it came true. 

[Carvers Gap]

The 12z Euro is one small, wintry system after another for our forum area.  It has some nice systems embedded.  I would be surprised if some in the forum don't score 1-2x w/ this trough...  The Euro is loaded up as well.

[Carvers Gap]

A great trend is the "re-stocking" of cold for NA.  During many recent La Ninas, NA would get emptied of cold, the trough would drop into the West, and winter was over outside of the Rockies.  I really don't see that pattern at all right now.  If anything, winter may just be getting started.

[Carvers Gap]

On another note, I sure hope JB referenced @GaWx w/ his phase 6 "isn't always warm" backtrack(from warmth) post.  Did he?  If he didn't, he needs to.....

[Carvers Gap]

28 minutes ago, Holston_River_Rambler said:

Nice slug of moisture incorporated into the Friday/ Saturday rain maker now:

WPC edging up precip forecast:

Give me that pipeline continuing w/ the incoming trough from the 11th-21st, and let's roll.  

[Carvers Gap]

The 12z EPS and GEPS are cold.  The GEPS is next level and probably has some usual cold bias in play.  The usually warm EPS...is picking up a very cold signal after the 20th as is the GEPS.  Remember, "normal" gets it done at this time of year.  I think the sharp cooling by ensembles might be driven by the NAO.  My short warmup after the 21s might be in trouble.  All ensembles are signaling a gradient pattern incoming.

[housemtnTN]

1 hour ago, John1122 said:

That's ice, their algorithm handles snow poorly. 

That said, it's a big winter storm East, South and West of us, so I wouldn't be shocked if it came true. 

Ahh. That's arguably worse for those areas which I cant image have more than a handful of snowplows!

[Daniel Boone]

1 hour ago, Carvers Gap said:

On another note, I sure hope JB referenced @GaWx w/ his phase 6 "isn't always warm" backtrack(from warmth) post.  Did he?  If he didn't, he needs to.....

He's not yet. He just, in another tweet, basically was hinging that Greenland Blocking was why, lol.

Of course, as we know, strong Greenland Blocking can mitigate even strong warm MJO effects. However, from Larry's research that is not what the reason was but, something to do with La nina and the location of it, if I remember correctly.

[Daniel Boone]

2 hours ago, John1122 said:

That's ice, their algorithm handles snow poorly. 

That said, it's a big winter storm East, South and West of us, so I wouldn't be shocked if it came true. 

It would be our luck.

[tnweathernut]

3 minutes ago, Daniel Boone said:

It would be our luck.

I mentioned a few days ago we do a really good job of kicking the can.  The other thing we seem to do well in the mid-south is whiff when the pieces of the puzzle on a large scale line up.  We've at least gotten past kicking the can for the ridge of doom in the Aleutians.  Now to see if we can buck the second thing we are good at between Jan 15 and 25th.   I'm cautiously optimistic.

[Carvers Gap]

30 minutes ago, Daniel Boone said:

He's not yet. He just, in another tweet, basically was hinging that Greenland Blocking was why, lol.

Of course, as we know, strong Greenland Blocking can mitigate even strong warm MJO effects. However, from Larry's research that is not what the reason was but, something to do with La nina and the location of it, if I remember correctly.

Good to have you back in here, man!!!  Hopefully you are feeling better.  It looks like we are gonna be needing u very soon w/ the pattern shaping up.  

The real story right now(in addition to the Jan 11-21 window), is the sharp cooking across ensembles d10+.  It wasn't there this morning.  But -10 to-15 departures at this range is interesting.  I gotta think some type of blocking is showing up...maybe a slower moving retrograding high, less prominent SER, OR as I suspect, the air mass in central Canada is gonna be legit and run the show.

[Carvers Gap]

19 minutes ago, tnweathernut said:

I mentioned a few days ago we do a really good job of kicking the can.  The other thing we seem to do well in the mid-south is whiff when the pieces of the puzzle on a large scale line up.  We've at least gotten past kicking the can for the ridge of doom in the Aleutians.  Now to see if we can buck the second thing we are good at between Jan 15 and 25th.   I'm cautiously optimistic.

I legit am kicking around trying to find my way to the Sierra Nevadas (sooner than later) for an atmospheric river event.  Vegas flights are cheap, but the drive....Reno is the best, but the connectors can be a problem.