867
FXUS64 KMRX 302346
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
746 PM EDT Mon Jun 30 2025

...New AVIATION...

.SHORT TERM...
(This evening through Tuesday)
Issued at 130 PM EDT Mon Jun 30 2025

Key Messages:

1. Scattered showers and thunderstorms this afternoon into tonight,
then greater coverage on Tuesday.

2. A few of the stronger storms may produce strong gusty winds, and
very heavy rain rates will bring flash flooding concerns for areas
that see repeated or prolonged heavy rains.

Discussion:

Isolated to scattered showers and thunderstorms are occurring this
afternoon, and coverage increase this afternoon before decreasing
during the evening hours with the loss of daytime heating. A few of
these storms may be strong to marginally severe, with strong gusty
winds the main threat along with the potential of very heavy
rainfall leading to localized flooding.

We will see height falls overnight as upper troughing approaches
from the west, which will keep the chance of weaker convection
around through the night into early Tuesday. The threat of severe
storms will be very low during this time frame, but the threat of
localized flooding will remain given the very moist environment.

For Tuesday, a weak cold front will be approaching from the west and
northwest, and while timing is still uncertain it may move into
western portions of our area by the end of the day.  This will
produce widespread showers and thunderstorms, especially during the
afternoon. Most areas are expected to receive rainfall on Tuesday.
MLCAPE will likely peak between 1000-2000 J/kg which will result in
some strong to severe thunderstorms capable of producing damaging
winds, but the chance of severe weather is low. Heavy rain rates
that may produce flash flooding will be the primary hazard on
Tuesday. With PW values around 2.0 to 2.2 inches, rain rates in
excess of three inches per hour are likely with stronger storms.
These heavy rain rates can quickly overwhelm urban and developed
areas with higher percentages of impervious surfaces, and other
areas that see repeated or prolonged heavy rains will be at risk for
flash flooding as well.

&&

.LONG TERM...
(Tuesday night through next Monday)
Issued at 130 PM EDT Mon Jun 30 2025

Key Messages:

1. Mostly dry weather for Wednesday through Saturday, with an
increase in isolated to scattered convection for Sunday and Monday.

2. Near normal high temperatures Wednesday, but then a gradual
warming trend with highs around 3 to 5 degrees above normal by
Friday into the weekend.

Discussion:

The frontal boundary will push off to our south and east by early
Wednesday, and any lingering convection Tuesday evening will move
out overnight.  Drier air will be moving in behind the front, and
Wednesday will be a mostly dry day with near normal temperatures,
although there is still a low chance of a shower or storm along our
eastern mountains closer to the departing front.

An upper ridge to our west will be building in Thursday into Friday,
and subsidence along with the drier air should keep us mostly
precipitation free. We will see a gradual warming trend, with
temperatures by Friday around 3 to 5 degrees above normal. The
mostly dry and hot weather will continue into the weekend, although
by Sunday into Monday models show some moistening of the atmosphere
and a better chance for isolated to scattered diurnal convection.

&&

.AVIATION...
(00Z TAFS)
Issued at 738 PM EDT Mon Jun 30 2025

Storm currently over CHA, otherwise TYS and TRI currently void of
any wx, however, there are some storms over the Smokies. VCTS
remains through at least 02z. Things should relatively clear
overnight with low chances for any fog or low CIG. More widespread
activity returns Tuesday with the approach of a frontal system.
Early afternoon lines with PROB30 have been added to this TAF
issuance to highlight a possible active last 6 hours of this TAF
period.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             72  87  70  90 /  30  80  30  10
Knoxville McGhee Tyson Airport, TN  72  87  70  89 /  50  80  30  10
Oak Ridge, TN                       71  86  69  90 /  50  90  30  10
Tri Cities Airport, TN              69  83  67  85 /  50  90  50  10

&&

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

$$

SHORT TERM...
AVIATION...KS