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

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249
FXUS64 KMRX 071848
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
248 PM EDT Mon Sep 7 2026

...New DISCUSSION...

.KEY MESSAGES...
Updated at 230 PM EDT Mon Sep 7 2026

- Showers and storms will be isolated to widely scattered this
  afternoon and evening.

- Drier conditions return for Tuesday and Wednesday with scattered
  to widespread showers and storms possible Thursday and Friday.

- Temperatures will be a few degrees above normal throughout the
  forecast period.

&&

.DISCUSSION...
Issued at 230 PM EDT Mon Sep 7 2026

An inverted surface trough will allow for isolated to widely
scattered chances of showers and storms this afternoon and evening,
primarily along and south of I-40. Latest mesoanalysis and model
derived soundings suggest MLCAPE will be limited to around 1000
J/kg. While lapse rates and shear will be poor, DCAPE near 1000 J/kg
could contribute to locally gusty winds under any activity that
becomes tall enough to produce lightning.

Activity will wane into the overnight and lead to a couple of dry
days as surface high pressure takes control Tuesday and Wednesday.
The main thing to note will be a slight warming trend as H5 heights
of 596-598dam build into the region behind a trough axis departing
the eastern seaboard. While not expecting record breaking heat like
our last heat wave, above normal temperatures persist.

By Thursday an upper level trough and associated jet is expected to
dip into the Great Lakes and northern Ohio Valley region. An
accompanying cold front will provide an axis of forcing leading to a
return of showers and storms by Thursday afternoon into Friday.
Lack of shear locally suggest limited chances of any strong to
severe weather. The main concern may be some training
precip/isolated flooding due to deep-layer flow being nearly
parallel to the front. An additional weak shortwave may continue
scattered to rain chances Saturday, with decreasing chances Sunday
into early next week as a ridge builds into the region.

&&

.AVIATION...
(18Z TAFS)
Issued at 100 PM EDT Mon Sep 7 2026

Clouds have been stubborn to leave the region today, hovering
around or just above the MVFR category. Expect they`ll continue to
burn off, but might not totally go clear. This will likely limit
afternoon convection, so have opted to leave out of the TAFs for
now.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             70  92  69  94 /   0   0   0   0
Knoxville McGhee Tyson Airport, TN  67  90  66  91 /  10   0   0   0
Oak Ridge, TN                       66  89  66  90 /  10   0   0   0
Tri Cities Airport, TN              61  86  60  87 /   0   0   0   0

&&

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

$$

DISCUSSION...KRS
AVIATION...99