832
FXUS64 KMRX 031833
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
233 PM EDT Wed Sep 3 2025

...New DISCUSSION, AVIATION...

.DISCUSSION...
Issued at 220 PM EDT Wed Sep 3 2025

Key Messages:

1. A cold front will bring increasing chances of a showers and
storms Thursday afternoon through the evening. A few storms may
become strong to severe with damaging winds the main hazard.

2. A second cold front will bring additional afternoon showers and
storms Saturday. Friday will be dry between the two systems.

3. Near to slightly above normal temperatures Thursday through
Saturday. Seasonally cool temperatures Sunday into early next week.

Discussion:

A broad and deep trough remains in place across the eastern half of
the CONUS. An impulse driving this morning and afternoons
precipitation will continue to lift through the southern and central
Appalachians tonight as an upper low settles into southern Canada
just north of the Great Lakes. The precipitation shield in
northeastern portions of the forecast area has largely dissipated,
with only isolated general showers or storms to occasionally
develop in wake this afternoon and evening.

An additional shortwave translating through mean flow aloft is
expected to drive a cold front towards the region tomorrow afternoon
and evening. While some precipitation cannot be ruled out with vort
lobes in the Thursday morning/mid day time frame, the main
convection of concern will be in the mid to late afternoon and
evening hours. Effective shear near 30kts will help to counteract
marginal CAPE around 1000-1200 J/kg. SPC convective outlook
maintains a marginal risk across the whole forecast area as a
result. The primary impact will be stronger to isolated damaging
gusts between 40-60mph. With freezing levels near 11kft some sub-
severe hail could be possible with the strongest storms as well.
Between 3pm to 10pm ET is the most likely timing.

Northwest flow fails to develop with this boundary, allowing for
near to slightly above normal temperatures Thursday through
Saturday. Friday should remain precipitation free, but additional
shortwave energy will send another front this direction Saturday.
NAMBufr soundings suggest effective shear closer to 20kts with
this wave, but more favorable instability near 1500J/kg(assuming
afternoon passage timing). Will be keeping an eye on this system
for the potential of another low end strong/severe threat.

Northwest flow develops behind the second front bringing seasonally
cool conditions to end the weekend. The expectations of weak flow
aloft and building surface high pressure will keep a precip free
forecast Sunday onward. Temperatures will gradually increase into
the middle of next week as well.

&&

.AVIATION...
(18Z TAFS)
Issued at 220 PM EDT Wed Sep 3 2025

A few showers or isolated thunderstorm are expected across the
area this afternoon and evening but conditions should remain VFR
outside of any convection. Due to low coverage, only VCSH included
in TAFs at this time.

Tonight, some low cloud or fog development is possible at TRI due
to this mornings rainfall. Have included a mention of IFR
conditions but depending on how much clearing occurs LIFR
conditions cannot be ruled out.

Southwest winds near 10kts develop with VFR conditions Thursday.
Inclusion of some showers/storms may be needed for later in
afternoon/evening with future TAF issuances. For now, just have a
prob30 of showers at CHA where the greatest chance for AM
precipitation exists.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             65  86  65  92 /  20  30  20   0
Knoxville McGhee Tyson Airport, TN  63  82  65  90 /  20  50  40   0
Oak Ridge, TN                       61  81  63  89 /  20  60  40  10
Tri Cities Airport, TN              58  78  61  85 /  10  50  30   0

&&

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

$$

DISCUSSION...
AVIATION...