December 2025 Short/Medium Range Forecast Thread

[housemtnTN]

Medium Flurry, dime size flakes in Mascot, TN about 10 mins ago.

[Carvers Gap]

The 18z RGEM has company…the 12z NAM.  Both are at range so the usual caveats apply.  The 18z GFS wasn’t too far off.

[Carvers Gap]

Haha.  If u want to see a wild swing, and it has been going on for a bit…look at 360 on the GFS at 18z and then flip back and look at 12z (temp anomalies).  We are talking 40-60 degree swings!  Good times.

[Carvers Gap]

The 18z GFS shows one of two extremes which have been modeled in the past 36 hours.  That is a crazy cold run.  Real feels have ranged from the 70s to below zero with these swings - for the same hour!!!

[midwoodian]

I created a Winter 25/26 general obs thread in case anyone sees some snow this AM 
[mention=10790]Knoxtron[/mention] and [mention=499]John1122[/mention] I'm staring at y'all with jealousy. 

Heavy flurries in Signal Mountain this afternoon


.

[Carvers Gap]

The last four runs of the GFS for Dec 12-17th.  

 

[Carvers Gap]

The 18z AIFS has 2-3 very strong cold fronts w/ the anafront ending the run.

[Carvers Gap]

[Carvers Gap]

The 0z 3kNAM and 0z RGEM show frozen precip over NE TN and SW VA over the weekend.  Just something to keep an eye on....

[John1122]

The UKIE, GGEM, and ICON show a winter event of varying degrees in the area. The Canadian would be a major winter storm with significant ice along the 40 corridor from the mid-state to the mountains. Some snow on top of the ice across areas north of 40. UKIE looks like a long duration sleet event. The ICON is a 1-2 inch snow north of 40.