Fall Branch, Tennessee Weather Forecast Discussion

444
FXUS64 KMRX 262343
AFDMRX
Area Forecast Discussion
National Weather Service Morristown TN
743 PM EDT Fri Sep 26 2025
...New AVIATION...
.KEY MESSAGES...
Updated at 734 PM EDT Fri Sep 26 2025
- Continued showery and unsettled weather through Saturday.
- Drier Sunday, but still a few showers and storms possible mainly
  north and east.
- Some guidance does show rain from a tropical system affecting
  the region during the coming week. However, the forecast is
  highly uncertain at this time.
&&
.DISCUSSION...
Issued at 115 PM EDT Fri Sep 26 2025
We start the period with an upper low located around the northern
Mississippi/Alabama border. This upper low will meander but will
make slow progress east and should be centered just to our
east/northeast by early Sunday. We will see showers and
thunderstorms associated with this system over our area today and
again on Saturday. The greatest coverage Saturday will be over
northern and eastern portions of the area. Convective energy looks
be modest at best and the severe storm threat very low, but
enough DCAPE should be available for a few spots to see gusty
winds associated with a stronger storm. The only other concern
with these showers and storms looks to be possible localized heavy
rain/flooding if any training were to occur. Sunday looks to be
mostly dry, although isolated showers and thunderstorms will be
possible mainly over northern and eastern areas.
For next week we are watching the tropics, where a disturbance in
the Caribbean is being monitored for development. There is a high
confidence that this system will further develop over the next day
or two, but there is very low confidence on the system`s future
track with models showing a very wide range of outcomes. There are
some solutions, although they are currently in the minority, that
show the system moving inland over the Carolinas and over or at
least close to the southern Appalachian region. This would of course
result in the potential for heavy rainfall. This will bear watching
as the system develops. However, given the majority of ensemble
members keeping the system well to our east with many keeping it off
the coast, the NBM just has low chances for showers and storms most
days for the coming work week.
&&
.AVIATION...
(00Z TAFS)
Issued at 734 PM EDT Fri Sep 26 2025
VCSH still possible for the next couple of hours. Showers are
light and have for the most part, lost lightning. Overnight will
bring the returned possibility of MVFR to IFR CIG and VSBY,
possibly LIFR to TRI. Kept with what was already there. For PM
hours Saturday, CHA appears will have the least probability of
TSRA, so have elected not to put a PROB30 there. TRI and TYS may
have activity fire off of or near the higher terrain.
&&
.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             65  83  64  84 /  20  30   0  10
Knoxville McGhee Tyson Airport, TN  64  81  63  82 /  20  50  10  10
Oak Ridge, TN                       63  81  61  82 /  20  40  10  10
Tri Cities Airport, TN              63  76  61  79 /  40  70  30  30
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DISCUSSION...99
AVIATION...KS

NWS MRX Office Area Forecast Discussion