Lafollette, Tennessee Weather Forecast Discussion

549
FXUS64 KMRX 270826
AFDMRX
Area Forecast Discussion
National Weather Service Morristown TN
426 AM EDT Sat Sep 27 2025
...Duplicate Key Messages Removed...
.KEY MESSAGES...
Updated at 425 AM EDT Sat Sep 27 2025
- Continued showery and unsettled weather today.
- Some showers could occur in the northeast on Sunday, but it should
be a mostly dry day.
- Uncertainty remains high for next week regarding any kind of
impacts from a tropical system approaching the SC coast next week.
Trends do seem to be moving in a direction that would favor less
impacts locally, but uncertainty is still high.
&&
.DISCUSSION...
Issued at 137 AM EDT Sat Sep 27 2025
Discussion
An upper low will shift eastward across the southern TN valley over
the next 24 hours or so. The proximity of this upper low will lead
to increased lapse rates aloft and should result in continued
isolated to scattered showers through the remainder of the night and
into the daytime hours today. The best coverage will likely be over
far northeast TN and into our Virginia counties, but they could
occur elsewhere. Expect mostly dry conditions on Sunday as this
feature pulls away towards the mid-Atlantic region. Temperatures
will continue to run 3-5 degrees above normal through the weekend.
Sunday onward the forecast becomes highly uncertain as the pattern
gets very complicated. A Mississippi valley ridge builds northeast
into the Ohio valley Sunday into Monday, which results in a sort of
rex block pattern by Monday as a tropical system, currently being
monitored in the Caribbean, approaches the SC coastline. Some
lingering energy from the departing southern Appalachian upper low
also gets pulled westward into the mix as well. All of that to say
that the forecast remains highly uncertain beyond Sunday as models
continue to show a decent spread of solutions with the upper pattern
and that approaching tropical system. As such, I mostly let the
forecast follow the NBM guidance for next week. It is worth noting
that there has been a significant shift in the guidance today in
favoring keeping this system along the coastline or even shifting it
east away from the coast instead of bringing it inland like they
were yesterday. Time will tell, but the trends seem to be moving in
the right direction.
&&
.AVIATION...
(06Z TAFS)
Issued at 146 AM EDT Sat Sep 27 2025
Fog is forecast again at all of the sites with the highest
confidence being at TRI. Reductions to IFR were maintained at
at TRI with MVFR for CHA and TYS. All sites should improve quickly
after sunrise with scattered showers and storms expected again
this afternoon. It is unclear if the terminals will be impacted
directly, but any storm could cause reductions to MVFR or less
with PROB30s maintained. Winds will be light and somewhat
variable.
&&
.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             83  63  85  65 /  20  10  10   0
Knoxville McGhee Tyson Airport, TN  81  63  82  63 /  40  10  10  10
Oak Ridge, TN                       80  61  82  62 /  40  10  10  10
Tri Cities Airport, TN              77  60  80  59 /  70  20  20  20
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DISCUSSION...CD
AVIATION...BW

NWS MRX Office Area Forecast Discussion