430 
FXUS64 KMRX 120549
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
149 AM EDT Thu Mar 12 2026

...New DISCUSSION, AVIATION...

.KEY MESSAGES...
Updated at 143 AM EDT Thu Mar 12 2026

- Light snow accumulation probable across highest ridgetops East
  TN and southwest VA mountains later this morning. Brief 
  changeover to snow also expected for some valley locations.

- Much colder today, warming trend Friday into the weekend. 

- Another round of showers and storms will move in by late Sunday
  or Sunday night, followed by a surge of sub-freezing
  temperatures

&&

.DISCUSSION...
Issued at 143 AM EDT Thu Mar 12 2026

The severe threat ended several hours ago and light to moderate rain 
showers will persist across the area through the rest of the night, 
along with continued breezy winds. The main story over the next few 
hours will be the surge of colder air that moves in later this 
morning, transitioning rain showers over to snow across the east TN 
and southwest VA mountains. Some valley locations, along with the 
northern Cumberland Plateau, will likely see a changeover as well. 
NAM soundings show this occurring between 09 and 12Z. This aligns 
very well with the latest HRRR hourly precip-type output. 

Valley locations east of I-75 and north of I-40 will have the better 
chances to see this brief window of snow. However, these areas are 
not expected to see any accumulation due to the recent warm spell 
and thus warmer ground temps. The highest elevations across the east 
TN mountains may see 1 to 2 inches, while isolated 0.5 to 1 inch 
amounts are possible across the mid elevations. Isolated 0.5 to 1 
inch amounts are also possible across the mountains of southwest VA. 
Lower elevations across southwest VA and extreme NETN may see a 
dusting. Latest NBM probs for greater than 0.5 inches of snow across 
the East TN and southwest VA mountains ranges between 60 to 70%. 
Models show the precip exiting east around 10 AM EDT. The window for 
snow will be brief, but once the changeover occurs, moderate snow 
rates are expected across some areas, and perhaps even some heavy 
rates as well. Areas that see the moderate, to possible heavy snow 
rates, will see reduced visibilities. 

Skies will clear this afternoon, but with lower elevation high temps 
only in the upper 40s to mid 50s. The mountains will stay in the 30s 
and 40s but with wind chills in the teens due to the continued 
gusty winds. 

Dry weather and a warming trend is expected Friday through Sunday, 
with highs back in the low to mid 70s. Then, more widespread rain 
and possible storms roll in Sunday night into Monday ahead of 
another cold front and deep upper trough. Some storms could be 
strong, depending on how much instability is in place. We will 
continue to keep an eye on this system as it approaches. 
Additionally, depending on the strength and alignment of the LLJ, a 
mountain wave event is possible Sunday into Monday morning across 
the East TN mountains and foothills. 

Much colder air is expected Monday and Tuesday behind the cold 
front. Overnight lows will be in the 20s on Monday and Tuesday 
night. High temps in the low to mid 40s are expected on Tuesday. We 
warm back up into the 50s on Wednesday as the deep trough lifts off 
to our northeast and high pressure begins to nose back in from the 
southwest.

&&

.AVIATION...
(06Z TAFS)
Issued at 143 AM EDT Thu Mar 12 2026

Band of steady rain to continue to move through the region
overnight tonight, front seems a little late to arrive versus
earlier TAFs so pushed out the wind pivot a couple hours. Rain
should be ending around 12z for KCHA and KTYS, rain to changeover
to snow at KTRI and end around 15z. Clouds are forecast to depart
not long after and result in rapid improvement to VFR. Gusty
northerly winds will weaken by or after sunset.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             57  37  66  41 /  20   0   0   0 
Knoxville McGhee Tyson Airport, TN  53  34  64  40 /  30   0   0   0 
Oak Ridge, TN                       54  34  63  40 /  10   0   0   0 
Tri Cities Airport, TN              49  29  61  36 /  50   0   0   0 

&&

.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&

$$

DISCUSSION...99
AVIATION...Wellington


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