169
FXUS64 KMRX 251749
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
1249 PM EST Tue Nov 25 2025

...New DISCUSSION, AVIATION...

.KEY MESSAGES...
Updated at 1244 PM EST Tue Nov 25 2025

- Wind Advisory remains in effect for the mountains and
foothills, and will be extended until 10 PM EST.

- Low probabilities for a few strong to severe storms this afternoon
and evening, mainly in the southern TN Valley.

- Drier and colder for Thanksgiving through Saturday.

- Chance of rain returns on Sunday.

&&

.DISCUSSION...
Issued at 1244 PM EST Tue Nov 25 2025

Showers this morning have been associated with a shortwave midlevel
trough and mid/upper level QG forcing in the right entrance region
of a jet. Convection has been elevated and very weak, with no
lightning observed for several hours. Some gusty winds have been
observed with the deeper convection, with gusts of 25-35 mph. Aloft,
a strong LLJ persists, as wind gusts at Cove Mountain have reached
50-55 mph, but have been trending down in recent obs. Other mountain
obs are showing gusts in the 25-35 mph range. So the Wind Advisory
will be alowed to end at 4 PM EST.

Convection is expected to develop across MS/AL over the next few
hours, and track toward the NE, associated with a surface pre-
frontal convergence zone. The question for our area is whether the
convection can maintain its intensity through an air mass that has
been thoroughly worked over this morning. Models do show some
surface-based CAPE developing around 3-5 PM in our southern TN
Valley counties, with weak elevated CAPE to the north. The severe
threat continues to look low, primarily straight-line wind gusts,
and mainly in the southern TN Valley and southern Plateau counties,
with a low tornado potential for the GA border counties where the
instability may be surface based and overlaps with some low level
shear. It is notable that the NAM shows 35-40 kt 0-1 km shear values
at the same time as 0-3 km CAPE around 100 J/kg. But I am skeptical
that much surface-based instability can be realized given the
morning rainfall and cloud cover - the NAM is often too aggressive
in bringing warm air north and eroding clouds. Overall, not much has
changed from the thinking of the previous forecast regarding the
severe threat.

A few light showers may linger through Wednesday morning as
northwest flow develops and tries to squeeze out any lingering
moisture, but mostly dry conditions are expected Wed afternoon
through Saturday. The main impacts will be anomalously low H5
heights bringing seasonally cool conditions around 10 degrees below
normal for Thanksgiving Day and Friday. Temperatures will slowly
rebound through the weekend, with lower confidence in rain chances
making a return by the latter half of the weekend into early next
week.

&&

.AVIATION...
(18Z TAFS)
Issued at 1244 PM EST Tue Nov 25 2025

Residual showers may impact terminals the next couple of hours
before redevelopment this afternoon and evening. CHA and TYS the
best chance of seeing TSRA. All terminals will bounce between VFR
and MVFR CIG and VSBY for the TAF period dependent on
precipitation. MVFR CIG forecast to hold after precipitation moves
out tonight. Southerly winds today will turn westerly tomorrow
ahead of the secondary cold front expected to bring much colder
air.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             53  58  34  50 /  50   0   0   0
Knoxville McGhee Tyson Airport, TN  53  57  31  46 /  80  10   0   0
Oak Ridge, TN                       51  56  31  45 /  70  10   0   0
Tri Cities Airport, TN              53  57  29  42 /  80  20   0   0

&&

.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...Wind Advisory until 4 PM EST this afternoon for Blount Smoky
     Mountains-Cocke Smoky Mountains-Johnson-Sevier Smoky
     Mountains-Southeast Carter-Southeast Greene-Southeast
     Monroe-Unicoi.

VA...NONE.
&&

$$

DISCUSSION...DGS
AVIATION...KS