374
FXUS64 KMRX 120653
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
253 AM EDT Thu Jun 12 2025

...New SHORT TERM, LONG TERM...

.SHORT TERM...
(Today and tonight)
Issued at 155 AM EDT Thu Jun 12 2025

Key Messages:

1. Scattered showers and thunderstorms are expected this afternoon
and evening.

Discussion:

In the upper levels, a trough is centered near AR/LA/TX today and
tonight. A ridge is over the Mid-Atlantic and Southeast. At the
surface, a stationary boundary will be over Northern AL/GA and
Northwest SC. With a trough to the west and high pressure to the
east, deep layer southerly flow will be pumping in moisture
bringing dew points into the 70s today for the Southern and
Central Tennessee Valley. PWat values will be around 1.5 inches
this afternoon. Heavy rain at times may cause localized flooding
issues. Instability will also be favorable for storms with CAPE
around 2000 to 2500 J/kg this afternoon and evening for most of
the Tennessee Valley. Some of the stronger storms may have gusty
winds. The freezing level will be very high making it difficult
for large hail to reach the surface. Temperatures will be warmer
in the mid to upper 80s. Rain chances will be low after midnight.

&&

.LONG TERM...
(Friday through Wednesday)
Issued at 155 AM EDT Thu Jun 12 2025

Key Messages:

1. Daily storms are expected with better coverage Friday onward.

2. Typical summer-like very warm and humid conditions each day.

Friday through Sunday

In the upper levels, a trough will be over the Mississippi River and
a ridge will be over the Mid-Atlantic. At the surface, high pressure
is centered over Eastern Canada and high pressure extends over the
Southeast U.S. from the Bermuda-Azores high over the Atlantic. A
stationary boundary will be between these two air masses likely
north of the Tennessee Valley. With a trough to the west and high
pressure to the east, deep layer southerly flow will be pumping in
moisture. PWat values will be around 1.5 and 2 inches through the
weekend. Heavy rain at times may cause localized flooding issues.
The best coverage for storms will be in the afternoon and evening
hours when instability is highest. CAPE will max out around 2000 to
3000 J/kg through the weekend. The main threat will be gusty winds
with the afternoon storms. The freezing level will be very high
making it difficult for large hail to reach the surface.
Temperatures will be warmer in the mid to upper 80s.

Monday through Wednesday

In the upper levels, the trough near the Mississippi River weakens
by Monday as the longwave ridge strengthens. By Wednesday, better
ridging will be over the Tennessee Valley. At the surface, high
pressure over Eastern Canada and high pressure over the Southeast
will be separated by a stationary boundary that may be closer to
the Tennessee Valley by this point. Regardless, deep layer
moisture advection will still be in place during this time with
deep layer southerly flow from the Gulf. As a result, there will
be good coverage of showers and storms during max heating in the
afternoon and evening hours.

&&

.AVIATION...
(06Z TAFS)
Issued at 121 AM EDT Thu Jun 12 2025

VFR conditions are expected outside of showers/storms. Scattered
showers and storms are expected late this afternoon and evening.
Some storms will have gusty winds and heavy downpours.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             88  70  88  71 /  40  20  70  50
Knoxville McGhee Tyson Airport, TN  86  68  87  70 /  50  20  60  40
Oak Ridge, TN                       87  67  86  69 /  30  10  60  40
Tri Cities Airport, TN              87  65  86  67 /  40  20  60  30

&&

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

$$

SHORT TERM...McD
LONG TERM....McD
AVIATION...McD