Area Forecast Discussion
Issued by NWS Knoxville/Tri Cities, TN

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745
FXUS64 KMRX 052323
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
623 PM EST Fri Dec 5 2025

...New AVIATION...

.KEY MESSAGES...
Updated at 1235 PM EST Fri Dec 5 2025

- Occasional drizzle could continue in the northern TN valley
  through this evening. Otherwise, dry but dreary conditions will
  be the norm through the first half of Sunday.

- Next system arrives Sunday night into Monday with very light
  precipitation. Some low elevation snow could occur in the
  north, but accumulations and impacts should be negligible.

&&

.DISCUSSION...
Issued at 1235 PM EST Fri Dec 5 2025

A northern branch jet will remain situated from the Arklatex region,
ENE through our forecast area and into the mid-Atlantic seaboard
through Saturday. With saturated low levels lingering in the
northern half of our CWA through at least late tonight, I wouldn`t
be surprised if areas of drizzle continue to show up from time to
time through late tonight. Otherwise, the forecast through Saturday
should be largely dry, though quite cloudy.

The next chance of precipitation looks to be Sun night into Mon
morning. We`ll be sandwiched between a southern stream
disturbance ejecting ENE from the southern plains along the
subtropical jet, and a stronger shortwave over the Great Lakes
associated with the polar jet during this time. There`s no strong
surface cyclogenesis in the southeast so any precip with this
system will be driven by jet dynamics aloft and should be light in
nature. There`s some indication that precip could miss us to the
north and south, focused with stronger jet support on either side
of us. However, model soundings show at least some moisture
present and higher resolution models do show some light precip.
Kept the high NBM PoPs because I think the likelihood that we get
something more than a trace of precip is pretty high, but this
will certainly be a high PoP/low QPF scenario. Regarding the
chances of winter weather, I did leave some snow in the forecast
for low elevations but certainly don`t believe there will be
impactful snowfall. Between the low QPF and the soundings showing
the potential for more of a seeder-feeder snowfall setup, there`s
very low chances of anything sticking, much less causing impacts.
For the higher elevations of northeast TN, the NW flow behind this
shortwave could result in a couple of inches through Monday
evening but that`s a low confidence part of the forecast right
now.

Tue and Wed look dry, but the next system arrives Wed night into
Thu, with better chances for widespread rainfall.

&&

.AVIATION...
(00Z TAFS)
Issued at 605 PM EST Fri Dec 5 2025

Will see low clouds/fog overnight into Saturday morning. MVFR to
IFR conditions will be common, and LIFR (or lower) conditions
will be possible especially at TRI later tonight into early
Saturday. Conditions will be improving to VFR Saturday afternoon.
Winds will generally be light.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             36  52  34  55 /   0   0   0  10
Knoxville McGhee Tyson Airport, TN  37  49  31  51 /   0   0   0  10
Oak Ridge, TN                       34  48  30  50 /   0   0   0  10
Tri Cities Airport, TN              36  45  28  49 /   0   0   0  10

&&

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

$$

DISCUSSION...CD
AVIATION...99