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FXUS64 KMRX 131115
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
715 AM EDT Sun Sep 13 2026

...New AVIATION...

.KEY MESSAGES...
Updated at 706 AM EDT Sun Sep 13 2026

- Widespread dense fog expected this morning.

- Dry for most of the area through the week with above normal
  temperatures continuing.

&&

.DISCUSSION...
Issued at 300 AM EDT Sun Sep 13 2026

Many locations have already developed dense fog, which is expected
to expand through the next few hours as rain affected most of the
area at some point yesterday. The latest model runs are quite
bullish on fog, even the HRRR, which doesn`t typically show much fog
in advance. A Dense Fog Advisory may be needed later tonight.

A shortwave trough will cross the OH Valley and central Appalachians
tomorrow afternoon and night, followed by a surface cold front. Most
CAMS are keeping the showers to our north, although the 00Z NAM
shows some light QPF in our northern sections as it brings the front
to our northern border by 12Z Monday. NBM still has no PoPs, and
will keep that going.

The backdoor front pushes through on Monday as a surface high moves
into the Mid Atlantic, but it will provide little to no relief from
the above normal temperatures (although dewpoints will be a little
lower behind the front). Aloft, a ridge will be over the Southeast.
Subsidence under this ridge will provide hot and dry conditions for
most of the area through the week. With forecast highs at CHA in the
lower to mid 90s each day, the streak of days reaching 90+ degrees
will continue (now at 40).

&&

.AVIATION...
(12Z TAFS)
Issued at 706 AM EDT Sun Sep 13 2026

Reductions due to low clouds and/or fog have been observed at CHA
and TYS and to a lesser degree at TRI. This should persist for the
next hour or two before gradual improvements into the late morning
and early afternoon. Other than some clouds around 5,000 to 10,000
feet, mostly clear conditions are expected with light northerly to
northwesterly winds. Fog is possible again tonight into tomorrow
morning but has been left out for the time being.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             94  70  96  70 /   0   0   0   0
Knoxville McGhee Tyson Airport, TN  90  68  90  67 /   0   0   0   0
Oak Ridge, TN                       90  68  90  66 /   0   0   0   0
Tri Cities Airport, TN              85  64  84  62 /  10  10  10   0

&&

.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...Dense Fog Advisory until 9 AM EDT this morning for Anderson-
     Blount Smoky Mountains-Bradley-Campbell-Claiborne-Cocke
     Smoky Mountains-East Polk-Grainger-Hamblen-Hancock-
     Jefferson-Knox-Loudon-McMinn-Meigs-Morgan-North Sevier-
     Northwest Blount-Northwest Cocke-Northwest Monroe-Rhea-
     Roane-Scott TN-Sevier Smoky Mountains-Southeast Monroe-
     Union-West Polk.

VA...Dense Fog Advisory until 9 AM EDT this morning for Lee.

&&

$$

DISCUSSION...DGS
AVIATION...BW