Rich Mountain Trail, Tennessee Weather Forecast Discussion

144
FXUS64 KMRX 202331 AAA
AFDMRX
Area Forecast Discussion...UPDATED
National Weather Service Morristown TN
731 PM EDT Sat Sep 20 2025
...New AVIATION...
.KEY MESSAGES...
Updated at 725 PM EDT Sat Sep 20 2025
-  Above normal temperatures will persist through early next
    week.
-  A few afternoon showers and storms will be around this
    afternoon through Tuesday. Coverage will be more isolated in
    valley locations but could become more scattered across higher
    terrain.
-  Chances for showers and storms will trend upward by the middle
    and latter portions of the work week. Potential of isolated
    severe storms but confidence is low.
&&
.DISCUSSION...
Issued at 128 PM EDT Sat Sep 20 2025
Currently, isolated to scattered showers and storms have
development across the higher terrain but having a hard time
moving into the valley. This is because of fairly strong CIN
across much of the region which will limit development until late
this afternoon/early evening. Best the instability is generally
along and east of interstate 75 with MLCAPES of 1500+. Hail CAPE
of 500-700 with mid-level lapse rates of 6-6.3 degrees. Can not
rule out an isolated strong storm late today with strong/gusty
winds and hail possible.
For tonight, patchy fog possible otherwise mostly clear.
Ensemble cluster analysis and deterministic models show surface
ridging remaining across the southern Appalachians with short-wave
to our west through Tuesday. Persistence will be the forecast with
isolated to scattered storms possible each day, mainly during the
afternoon/early evening, with greatest coverage over the higher
terrain.
A strong upper trough will dig into the mid-section of the nation
for mid-week then into the Tennessee valley for the later half.
Ensemble clusters do show some variance in exact location of this
trough and potential instability. Greater coverage of showers and
storms are likely for the latter half of the week. There is a
potential of isolated severe storms as well but confidence is low
at this time.
&&
.AVIATION...
(00Z TAFS)
Issued at 725 PM EDT Sat Sep 20 2025
Two main forecast concerns for the 00z TAF period are the
potential for fog at KTRI tonight, and then the likelihood of
SHRA/TSRA affecting any terminals tomorrow afternoon. Rainfall
this afternoon would suggest there`s a good possibility of fog
tonight at KTRI but we`ve been so dry recently that confidence in
it occurring is low. Have left it out for now because of that and
will reassess in 06z package. Tomorrow should be similar to today
with respect to SHRA/TSRA development. High confidence they`ll be
around, mainly over the higher terrain, but low confidence in them
affecting terminals. Have left out for that reason.
&&
.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             66  89  67  88 /  10  20  30  30
Knoxville McGhee Tyson Airport, TN  63  87  64  86 /  10  20  20  30
Oak Ridge, TN                       63  87  64  85 /  10  20  20  40
Tri Cities Airport, TN              60  83  60  82 /  20  10  10  40
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DISCUSSION...DH
AVIATION...CD

NWS MRX Office Area Forecast Discussion