173
FXUS64 KMRX 071749
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
1249 PM EST Sun Dec 7 2025

...New DISCUSSION, AVIATION...

.KEY MESSAGES...
Updated at 1246 PM EST Sun Dec 7 2025

- Overnight expect precipitation to move in. Light snow
  accumulations are expected, primarily across the higher
  elevations of northeast Tennessee and southwest Virginia.

- A Winter Weather Advisory has been issued for late tonight into
  Monday. The Monday morning commute in these counties could be
  impacted by accumulating snow, or reduced visibilities from
  falling snow.

&&

.DISCUSSION...
Issued at 1246 PM EST Sun Dec 7 2025

Primary forcing for precipitation will be associated with a midlevel
shortwave trough, with model guidance showing little in the way of
organized surface forcing. Therefore, precipitation amounts are
expected to remain light throughout the event. Measurable
precipitation should start generally between sunset and midnight as
the column slowly moistens closer to the surface. By early Monday
morning, cold air advection strengthens behind a weak low-level
trough and attendant surface cold front, resulting in falling
temperatures and a transition to snow across northern portions of
the forecast area. This transition will be most notable in southwest
Virginia and the eastern Tennessee mountains. Outside of the highest
terrain, accumulations will be fairly limited. In the higher
elevations of northeast Tennessee, persistent northwest flow in the
wake of the shortwave may yield localized accumulations of 13
inches through Monday evening, primarily along mountain peaks near
the North Carolina border.

While much of the counties look to see snowfall totals technically
remain below Advisory criteria, have opted to issue a Winter
Weather Advisory since the ridge lines could see up to 3
inches... In addition the Monday morning commute could very much
be impacted as light to (possibly at times) moderate snow is
coming down. This is a very low end advisory, but Monday morning
driving conditions are the main concern with this event.

A generally zonal flow regime is anticipated through midweek,
supporting modest warming with highs reaching the 50s by Wednesday.
The next synoptic system approaches late in the week, with
temperatures initially mild ahead of the front, followed by a
pronounced cold advection behind the low and frontal passage
Thursday into Friday. A much colder air mass is forecast to settle
in for the weekend, with morning lows potentially in the teens and
daytime highs limited to the 20s and 30s.


&&

.AVIATION...
(18Z TAFS)
Issued at 1246 PM EST Sun Dec 7 2025

Low confidence forecast. Clouds are extremely stubborn to clear out
of KCHA, but should start to break up in the next couple of hours.
Cold rain moves in overnight and will likely drop conditions down
below MVFR categories, but low  confidence on how far they drop with
some guidance going to VLIFR and others barely dipping below MVFR.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             41  50  29  52 /  40  10   0   0
Knoxville McGhee Tyson Airport, TN  38  44  28  50 /  40  30   0   0
Oak Ridge, TN                       38  45  27  48 /  30  20   0   0
Tri Cities Airport, TN              35  40  27  44 /  50  80  10   0

&&

.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...Winter Weather Advisory from 1 AM to 7 PM EST Monday for Johnson-
     Southeast Carter-Unicoi.

VA...Winter Weather Advisory from 1 AM to 7 PM EST Monday for Russell-
     Washington VA-Wise.

&&

$$

DISCUSSION...99
AVIATION...99