Birchwood, Tennessee Weather Forecast Discussion

726
FXUS64 KMRX 251720
AFDMRX
Area Forecast Discussion
National Weather Service Morristown TN
120 PM EDT Thu Sep 25 2025
...New DISCUSSION, AVIATION...
.KEY MESSAGES...
Updated at 117 PM EDT Thu Sep 25 2025
-  Scattered thunderstorms this afternoon into the evening. Flood
    risk is low today, and a few storms could contain breezy
    winds.
-  Friday and Saturday are likely to have scattered light rain
    showers. Low rain chances continue into next week.
&&
.DISCUSSION...
Issued at 117 PM EDT Thu Sep 25 2025
Currently an upper-level trough currently positioned over the
Midwest will continue it`s journey into the Ohio Valley the rest of
today and into tomorrow. This system will eventually ejecta weak
upper low that will drift across portions of the Eastern U.S.
through the weekend. A few light showers still linger early this
afternoon, but the majority of todays rainfall is expected to
develop in the afternoon. As daytime heating increases, moderate
instability will build, with 500 to 1000 J/Kg of MLCAPE and
effective shear around 30 knots. However, weak lapse ratesgenerally
likely limit storm intensity. Based on yesterdays performance of
weak updrafts, similar storm intensity is expected this afternoon
and people with outdoor activities should stay aware of isolated
storms which may produce brief heavy downpours and gusty winds.
Looking forward to more repeated rounds of showers and storms over
the weekend and into next week as this system slowly moves through.
Multiple rounds of rain have been spaced out by long dry intervals,
allowing soils to absorb moisture gradually. While some areas remain
saturated, most locations would require several inches of rain to
trigger flooding according to Flash Flood guidance. Nevertheless,
isolated thunderstorms could still produce localized heavy rain. If
you encounter water-covered roads, turn arounddont risk driving
through flooded areas.
Tomorrow into the weekend light rain remains possible, particularly
across northeastern Tennessee and southwestern Virginia, due to
lingering instability from the upper trough. The flood risk remains
very low. Diurnal shower chances will persist into next week, but
widespread activity is not expected. Temperatures will remain
relatively steady through the period, with a slight cooling trend
possible late next week. If you have outdoor activities planned this
weekend keep an umbrella handy!
&&
.AVIATION...
(18Z TAFS)
Issued at 117 PM EDT Thu Sep 25 2025
Isolated showers will continue this afternoon, eventually turning
into isolated thunderstorms. Low confidence on the timing of the
storms due to the isolated nature of them. Expect mid to low
ceilings to linger for the remainder of the night even after the
storms have moved through.
&&
.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             66  82  64  82 /  30  30  10  30
Knoxville McGhee Tyson Airport, TN  66  79  63  79 /  50  40  30  50
Oak Ridge, TN                       64  79  62  79 /  40  30  30  50
Tri Cities Airport, TN              64  78  61  77 /  40  50  50  70
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DISCUSSION...99
AVIATION...99

NWS MRX Office Area Forecast Discussion