102
FXUS64 KMRX 011744
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
144 PM EDT Fri Aug 1 2025

...New DISCUSSION, AVIATION...

.DISCUSSION...
Issued at 143 PM EDT Fri Aug 1 2025

Key Messages:

1. A cooler and drier air mass is moving into the region behind a
cold front. High and low temps will be below normal into next week.

2. Rain chances continue through much of the forecast period as
a broad mid/upper trough lingers over the eastern U.S.

Discussion:

Current obs and latest WPC surface analysis have a cold front just
south of the region along the TN/GA border. Current satellite
imagery shows a healthy Cu field over the region with thick clouds
just upstream over East KY and Middle TN. Showers and storms will be
isolated this afternoon/evening north of I-40 and west of I-81.
Farther south and in the mountains, showers and storms will be more
scattered closer to the frontal boundary. There is still a low end
chance for localized gusty winds and flash flooding with the
strongest storms, like previous days. Instability is still good
today with CAPE around 2000 J/kg near the mountains. A cooler, drier
air mass has already moved into the region behind the cold front as
high pressure centered over the Upper Midwest brings a Canadian air
mass southward.

This weekend, scattered showers and storms are expected in the
afternoon/evening hours with isolated activity possibly continuing
into the overnight hours as an upper level trough sits over the
Eastern U.S. Also an inverted surface trough will be near the TN
Valley this weekend aiding in lift. Instabilty will be lower over
the weekend with CAPE around 1000 J/kg or less. Pwat values will be
lower although still decent around 1.75 inches this weekend, so
isolated flooding issues will still be possible but probably not
widespread. Temps will be cooler than normal with highs in the upper
70s and lower 80s.

Early and mid next week, daily thunderstorm chances will be isolated
to scattered each afternoon/evening as a trough lingers over the
Lower Mississippi and Tennessee Valleys. Temps will be cooler than
normal with highs mainly in the lower 80s.

&&

.AVIATION...
(18Z TAFS)
Issued at 143 PM EDT Fri Aug 1 2025

Showers and storms will be scattered near the terminals this
afternoon/evening. Showers and storms are starting to develop on
radar and a healthy Cu field is in place in the Tennessee Valley.
The threat for fog late tonight is lower than previous nights with a
drier air mass moving into the region behind the cold front but MVFR
CIGs and vis will still be likely.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             70  84  70  79 /  20  70  60  70
Knoxville McGhee Tyson Airport, TN  70  82  69  79 /  30  70  70  70
Oak Ridge, TN                       69  82  68  79 /  20  60  60  70
Tri Cities Airport, TN              67  78  64  78 /  30  60  50  40

&&

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

$$

DISCUSSION...McD
AVIATION...McD