894
FXUS64 KMRX 281059
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
659 AM EDT Tue Jul 28 2026

...New AVIATION...

.KEY MESSAGES...
Updated at 655 AM EDT Tue Jul 28 2026

- Isolated to scattered strong to possibly severe showers and
thunderstorms will move in later this morning, primarily impacting
northeast Tennessee into southwest Virginia through the afternoon
and early evening. Damaging winds the primary threat with isolated
flash flooding. Low-end threat for severe hail or tornadic activity.

- Hot and humid conditions continue today. Heat indices in the upper
90s to low 100s can be expected, especially in the central and
southern valley.

- Mostly dry conditions with temperatures steadily holding just
below normal tomorrow into next weekend. Precipitation chances
return as early as Saturday.

&&

.DISCUSSION...
Issued at 117 AM EDT Tue Jul 28 2026

As anticipated and forecasted by the models, a weakening and dying
MCS is currently entering the forecast area from KY. Lightning
activity has greatly fallen off before it reached our CWA border. We
do not anticipate severe storms, but a minor gust of wind cannot be
ruled out. Middlesboro, KY just after 12:30 gusted to almost 30 mph.
Decent CAPE, DCAPE, and EBShear are present for this time of night;
2500 J/Kg, and almost 40 KT Effective.

Later this morning into the afternoon and possibly early evening
hours, still holds fairly low confidence on evolution of activity
today in regards to, strength, timing, location, and hazards besides
damaging wind gusts. Timing for the frontal passage itself will be
between 2 and 8 pm ET. The latest HRRR depicts another round of
showers and storms will barrel down from the Ohio Valley region
around sunrise and after. A few samplings of forecast soundings over
southwest VA show strong to severe storm capability, with increasing
vertical shear. There may be parts of the forecast area, in
particular, southwest VA, that may see repeated rounds of
precipitation from this morning into the afternoon, which raises the
concern for flooding from training storms. QPF totals vary from the
HRRR to the RRFS, though the RRFS tries to bring chances a bit
further south, meanwhile, the HRRR keeps activity restricted to the
northeastern sector of the CWA. In all, the instability will surely
be there (will it be impacted by morning activity?), moisture is
surely present, and forcing coming from the front will bring
scattered showers and thunderstorms for much of the day with some
strong to severe capability. The main hazard still remains damaging
wind gusts, with isolated flash flooding from heavy rainfall and
possible training. Smaller than 1 inch hail could be possible, as
well as well as a tornado, given the increase in shear and SRH later
today.

Before getting into the rest of the forecast period, which won`t be
much to touch on at all, it will be hot and humid again later today.
Southwest VA into northeast TN may escape the hottest conditions, as
well as the Southern Appalachians, but that goes without saying.
Upper 90s to mid 100s for heat indices today from the central valley
south to the GA border (southern valley).

Tomorrow into the first weekend of August will see temperatures
dropping to just below normal and for the most part, holding steady
as lower heights from the western side of the trough sink south.
Humidity will also trend lower into Thursday before a trend upward
begins Friday. Surprisingly enough, once we clear things out of here
late tonight, dry weather will most likely persist into early
Saturday before precipitation chances creep back in. Surface high
pressure at that time, begins to be replaced by another shortwave
lobe and a system possibly moving in from the NW.

&&

.AVIATION...
(12Z TAFS)
Issued at 655 AM EDT Tue Jul 28 2026

Isolated showers will move through near the KTRI airport this
morning with minimal categorical impacts. More robust convection
will likely move through late this morning into the afternoon.
Convection will be scattered enough that there is low confidence
on specific timing of impacts at the airport, but strongest storms
could have gusty winds and heavy downpours briefly.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             96  73  90  67 /  20  20   0   0
Knoxville McGhee Tyson Airport, TN  93  71  87  64 /  60  30  10   0
Oak Ridge, TN                       93  69  87  64 /  50  10   0   0
Tri Cities Airport, TN              86  66  82  59 /  90  30   0   0

&&

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

$$

DISCUSSION...KRS
AVIATION...99