775
FXUS64 KMRX 170547
AFDMRX
Area Forecast Discussion
National Weather Service Morristown TN
147 AM EDT Tue Mar 17 2026
...New DISCUSSION, AVIATION...
.KEY MESSAGES...
Updated at 122 AM EDT Tue Mar 17 2026
- Light scattered snow showers to continue into today, may continue
into the afternoon before tapering off. Medium potential for
additional snow accumulations.
- Cold weather to continue today through tomorrow morning before
a gradual warming trend occurs and returns the region to warm
weather by the weekend. Mostly dry conditions midweek through
the weekend.
&&
.DISCUSSION...
Issued at 122 AM EDT Tue Mar 17 2026
Current radar necessitated an extension in time of the winter
advisory, and snow showers are expected to continue overnight. Some
secondary and local roads have become snow covered or remain wet, so
be wary of black ice in the early morning with temperatures in the
20s over much of the area.
The upper axis of the anomalous upper trough will be swinging
overhead today, which will bring an end to the scattered snow
showers and flurries as this trough swings by. Temperatures aloft
are quite cold, with the 850 mb layer at dendritic favorable
temperatures. Result is high temperatures in the northern valley
into Virginia will struggle to reach or exceed freezing, especially
for those with snow on the grass. The ending time for the snow
showers is a bit uncertain. The HRRR is the more aggressive model,
and yet is still reasonable showing another round of snow showers
with another 1 inch of accumulation across southwest Virginia. HREF
and REFS aren't as aggressive overall, so for now will forego an
extension in the winter advisory to 8 pm tonight, through if
confidence increases later, that is an option.
A weak clipper swings through on Wednesday, and its just gotten into
range of the CAMs, which show just light precipitation. A dry air
layer at the surface will be working to counteract the
precipitation. NBM is entirely dry during this period, so added in
low PoPs to account for the light snow/rain mix that's possible with
this shortwave. QPF is light enough that anything that does fall
shouldn't be impactful.
Beyond Wednesday we return to a warming trend as the upper troughs
depart, higher heights move in, and westerly flow advects warm air
from the western US over to the eastern US. We'll return to warm
temperatures this weekend. There's pretty good agreement between the
GFS and Euro on a flat cold front crossing from north to the south
at the start of next week. More uncertainty exists as to the degree
and timing of any precipitation with that front. Due to the front's
orientation and the wind flow aloft, no significant weather concerns
exist for the back half of the forecast period.
&&
.AVIATION...
(06Z TAFS)
Issued at 122 AM EDT Tue Mar 17 2026
The best weather will be at CHA with scattered clouds and slightly
gusty westerly winds during the daytime. At TYS, MVFR CIGs are
expected in the early morning hours through mid to late morning.
Westerly winds will be gusty at times. At TRI, snow showers
continue but appear lighter on radar than 2-3 hours ago. Light
snow should be ending completely by early morning. MVFR CIGs are
expected through mid to late morning. Winds will be gusty in the
afternoon.
&&
.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN 45 29 55 35 / 0 0 0 0
Knoxville McGhee Tyson Airport, TN 40 25 50 34 / 10 0 10 0
Oak Ridge, TN 40 25 50 33 / 10 0 10 0
Tri Cities Airport, TN 35 19 45 31 / 20 0 10 0
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...Winter Weather Advisory until 8 AM EDT this morning for Blount
Smoky Mountains-Cocke Smoky Mountains-Johnson-Sevier Smoky
Mountains-Southeast Carter-Southeast Greene-Southeast
Monroe-Unicoi.
VA...Winter Weather Advisory until 8 AM EDT this morning for Lee-
Russell-Washington VA-Wise.
&&
$$
DISCUSSION...99
AVIATION...99
--- MBSE BBS v1.1.7.1 (Linux-x86_64)
* Origin: Outpost BBS * Johnson City, TN (618:618/1)
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