January 2026 Short/Medium Range Thread

[Carvers Gap]

I am gonna have to see some support from the AI ensembles before I buy the AI deterministic runs.  The 18z AIGEFS is further south than its 12z AIGEFS run and south of the 18z deterministic run.  The AIFS EPS was much colder than its 12z deterministic run.  If the 18z AIFS EPS comes in south w more hp...I think the deterministic still has some room to move.

[Carvers Gap]

2 minutes ago, TellicoWx said:

@Carvers Gapyou asked earlier about verification...best could find, not alot out there. This is released once a month i think.

And that AIFS ensemble was honking for a winter storm at 12z.  Let's see what 18z does.  Looks to me like AIFS Euro, then EPS, then Euro???  The AIFS (at that time) deterministic looks a bit down there, but I can't really tell.  I agree w/ the top 3 if so.  Though the AIFS EPS is a bit to snowy as a bias.  

[Holston_River_Rambler]

Regular old Euro is kicking the Baja low out at 18z too. 

[John1122]

Another long duration freezing rain event on the AI from the Plateau and points west. I hope we can get a favorable trend with it but it locks on like a dog with a bone and doesn't often waiver much. And for better or worse it usually ends up closer to actual events than other models. That seems especially true inside d5. 

[Carvers Gap]

The 18z Euro(non AI) makes a lot of sense.

[Holston_River_Rambler]

Just now, Carvers Gap said:

The 18z Euro(non AI) makes a lot of sense.

It also makes me glad my father on law bought us a generator. 

[TellicoWx]

7 minutes ago, Carvers Gap said:

I am gonna have to see some support from the AI ensembles before I buy the AI deterministic runs.  The 18z AIGEFS is further south than its 12z AIGEFS run and south of the 18z deterministic run.  The AIFS EPS was much colder than its 12z deterministic run.  If the 18z AIFS EPS comes in south w more hp...I think the deterministic still has some room to move.

If you like snow in the eastern valley that wasn't it verbatim lol (temps went up a little more, that trend started at 18z yesterday). Will be interesting what the ENS say.

[Carvers Gap]

The BIG difference is how the AI models are handling hp.  They are quicker to move it east which allows precip to nose northward.  The deterministic runs hold much more hp behind the system.  I will have to look at trends to see if one set is moving to another.

[Holston_River_Rambler]

hour 141 on the normal Euro:

[Carvers Gap]

1 minute ago, TellicoWx said:

If you like snow in the eastern valley that wasn't it verbatim lol (temps went up a little more, that trend started at 18z yesterday). Will be interesting what the ENS say.

The AIFS has never really been snow for the eastern valley, but its ensemble has.  I haven't looked at the 18z ensemble yet.  The actual operational Euro look about right IMHO.

[TellicoWx]

May need WSW for Jacksonville and Orlando toward end of AIFS run lol

[Weatheriscool]

6 minutes ago, Holston_River_Rambler said:

hour 141 on the normal Euro:

This appears to be a long duration event, that alot of overrunning

[Holston_River_Rambler]

Euro AIFS Ensemble is pretty resolved to kick out the Baja low, but seems to have some divergent members once it gets inland:

[Matthew70]

9 minutes ago, Holston_River_Rambler said:

hour 141 on the normal Euro:

Man that I40 split is so evident on that shot. 

[Holston_River_Rambler]

FWIW here are the Euro AIFS ensemble member mslps at hour 144:

[TellicoWx]

Can tell there is starting to be a real threat possibly of a major winter impact storm. Eastern valley is having to thread a needle potentially, so to speak...even 93 had to thread the needle.

[Carvers Gap]

I like the 18z Euro(non AI) and 18z Euro AIFS EPS.  The look almost identical.  Ice to snow over NE TN.  May even start as some light run.  The AIFS EPS pushes the cold front in quickly as soon as precip starts.  That cold air just crashes into the system.  

[Holston_River_Rambler]

Normal EPS MSLPs

[CheoahBald1]

Stupid question probably but does the 18z euro just go out to 144 hours on pivotal?


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[Matthew70]

Lots to consider this week.  Long duration event.  Very little if any melting for several days. Possibly ice storm that COULD disrupt electricity.  Very cold temps following this event.  Just a big ole mess. 

[Matthew70]

1 minute ago, CheoahBald1 said:

Stupid question probably but does the 18z euro just go out to 144 hours on pivotal?


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Yes

[CheoahBald1]

Yes

Thanks. Hopefully the border counties (ETN & WNC) isn’t a cold rain the whole event …


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[Carvers Gap]

I am gonna ride w/ ensembles for about 24-36 more hours, and watch deterministic runs for trends.  I don't use the AIGFS stuff.   I barely use the GFS.

Overall trends:

18z Euro(only to 144): trend north w/ ice over much of the forum, but...sure looks like the second wave would be snow.  

18z EPS(only to 144):  Looks super steady...maybe a tick north.  Looks ready to deliver the goods.  Looks remarkably similar to the AIFS Euro.  I trended a hair colder.

18z AIFS: Slight trend north, and northernmost of all guidance.  Looks a little overly aggressive w/ the warm nose, but that has precedent for sure.

18z AIFS EPS: Slight trend north but the accumulation map has barely changed at all. Temps barely budged.  Steady.

18z GFS: Slight trend north, and southernmost of all guidance

18z GEFS:  Accumulations are much higher than previous runs

Things to watch....we need a true banana high over the top without a hp slipping eastward too quickly.  I highly doubt models have this nailed at this range.   IF(huge IF) the GFS is half right, then the followup waves will almost certainly be frozen for E TN.  It does look like a multi day event.  E TN for sure will have to watch the precip axis.  I can just about guaranteed modeling will continue w/ its ebb and flow.  NW TN looks favorable w/ this setup as it normally does.  Middle looks good.  E TN north of I40 probably is ice to snow.  Crapshoot south of that...and maybe a crapshoot in NE TN. 

FWIW, one of those 93-94 or 95-96 events(maybe both!!!) started out as freezing rain during an over-running event and switched to snow.  I think we see that setup.  TBD on rain/snow/ice lines.  

I may try to do the late night suite tonight, but my tradition is to look at those in the AM along w/ 6z and then post at 12z.  

[Carvers Gap]

24 minutes ago, Holston_River_Rambler said:

FWIW here are the Euro AIFS ensemble member mslps at hour 144:

Better than tracking SLPs in the Lakes!!!

[Carvers Gap]

Eyes -> 18z GEFS  and 18z AIFS EPS snow means for the entire run.

[WishingForWarmWeather]

2 hours ago, housemtnTN said:

TWC app actually shows snow Saturday and sunday with estimated amounts. It never calls for snow this far out lol.

Said the same thing to my husband and kids. It’s snowing 1-3 across Friday night, Saturday morning, Saturday night. So “3-9” total. It NEVER shows snow out this early. 

[Uncle Nasty]

Said the same thing to my husband and kids. It’s snowing 1-3 across Friday night, Saturday morning, Saturday night. So “3-9” total. It NEVER shows snow out this early. 

It even mentions "Watching a potential winter storm" for Chattanooga.



Sent from my SM-S916U using Tapatalk

[WishingForWarmWeather]

7 minutes ago, Uncle Nasty said:

It even mentions "Watching a potential winter storm" for Chattanooga.



Sent from my SM-S916U using Tapatalk
 

Yeah I’m incredibly surprised because they are usually last to settle down with calling stuff. Especially before any of the National Weather folks do. 
 

fingers crossed you get snow in Chatt!!!!!

 

 Edit: just checked and twc now also days watching potential winter storm for me in Clarksville as well 

[Icy Hot]

Somebody wake up Stovepipe. 

[midwoodian]

Yeah I’m incredibly surprised because they are usually last to settle down with calling stuff. Especially before any of the National Weather folks do. 
 
fingers crossed you get snow in Chatt!!!!!
 
 Edit: just checked and twc now also days watching potential winter storm for me in Clarksville as well 

I’ve noticed TWC is always slow to lock in total. But probably now auto-written by AI with less quality human review. Or I’m being pessimistic.


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