632 
FXUS64 KMRX 251750
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
150 PM EDT Wed Mar 25 2026

...New DISCUSSION, AVIATION...

.KEY MESSAGES...
Updated at 148 PM EDT Wed Mar 25 2026

- Relative humidities will improve Thursday helping to lower fire 
  concerns.

- Light rain returns late Friday, generally for locations along
  and north of I-40. 

&&

.DISCUSSION...
Issued at 148 PM EDT Wed Mar 25 2026

The next several days will be characterized by a significant 
transition from above normal warmth to a more active, cooler pattern 
over the weekend. It will warm up to above seasonal temperatures 
again through midweek.

Currently, a potent 500mb ridge is centered over the southern 
Plains, where it's driving high temperatures 20ΓÇô30 degrees above 
seasonal norms. This ridge will shift eastward through Friday, with 
H5 heights rising across the Tennessee Valley and supporting surface 
temperatures as high as 84 degrees. 

In the low levels, a persistent low level ridge over the Carolinas 
is maintaining dry conditions and low relative humidity (20ΓÇô30%) 
over the Appalachians, though a strengthening westerly LLJ will 
begin to transport modest moisture ahead of a trailing shortwave by 
late Thursday.

By Friday night and into Saturday, the synoptic setup shifts as a 
surface cold frontΓÇödriven by an upper level low tracking across the 
northern tierΓÇödigs into the Tennessee and Ohio Valleys. Sounding 
data and model ensembles suggest a weakening trend for this system 
as it moves south, due to a loss of upper-level dynamics and limited 
Gulf moisture return. However, soundings indicate enough boundary 
layer instability for scattered showers, particularly for areas 
north of I-40. Post-frontal northwest flow will bring a surge of 
cooler, Canadian air and breezy conditions for the weekend, with 
temperatures dropping significantly to restore more seasonal 
conditions by Sunday.

The primary impacts for the period center on fire weather and 
temperature fluctuations. Before the Friday frontal passage, the 
combination of record heat and low afternoon humidity (below 30%) 
will create a window of increased fire danger, particularly in the 
southern Tennessee Valley and North Carolina mountains where drought 
conditions have been persistent. Following the front, a second 
impact will be the enhanced post-frontal winds, with gusts of 20ΓÇô30 
mph possible across the higher terrain of the Smoky Mountains and 
Southwest Virginia on Saturday. Ensemble QPF means are generally 
under 0.10 inches for most of the region. A return to near-normal 
temperatures is expected by the middle of next week as the ridge 
loses its influence.

&&

.AVIATION...
(18Z TAFS)
Issued at 148 PM EDT Wed Mar 25 2026

VFR TAFs though there's a low probability for MVFR conditions 
tomorrow morning, but for now kept it as a SCT deck. Dry weather to 
continue. Late in the period, strengthening flow aloft will allow 
for stronger SW flow, with gusts at TYS to near 20 to 25 knots 
beginning around the end of the TAF period.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             55  82  60  84 /   0   0   0  20 
Knoxville McGhee Tyson Airport, TN  53  80  62  79 /   0   0   0  60 
Oak Ridge, TN                       53  80  60  79 /   0   0   0  70 
Tri Cities Airport, TN              48  76  58  74 /   0  10   0  80 

&&

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

$$

DISCUSSION...99
AVIATION...99


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