366 
FXUS64 KMRX 221905
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
305 PM EDT Fri May 22 2026

...New DISCUSSION...

.KEY MESSAGES...
Updated at 230 PM EDT Fri May 22 2026

- Scattered to numerous showers and storms this afternoon and
  evening, a few of which may become strong to severe. Primary 
  concerns are locally heavy downpours, strong to damaging winds, 
  and the potential for a few brief and weak tornadoes. 

- Gusty winds expected in portions of the East Tennessee mountains
  and adjacent foothills tonight.

- Daily chances of showers and storms exist each day though the 
  forecast period. 

&&

.DISCUSSION...
Issued at 230 PM EDT Fri May 22 2026

The upper level pattern consists of a longwave trough over western 
portions of the CONUS and ridging over the southeast. An impulse is 
currently traversing mean flow atop the northern Gulf states and 
into the Tennessee Valley. A sfc warm front is also draped through 
the eastern TN Valley and wrapping back westward toward Memphis, 
where an area of surface low pressure is developing. This pattern 
has continued to promote numerous showers and storms across the 
region. Convective activity will increase in coverage for our county 
warning area as the upper shortwave translates across this 
afternoon and evening. 

Latest RAP and HRRR soundings depict around 500 to 1000 J/kg MLCAPE 
as a southwesterly LLJ near 40kts promotes effective shear near 25-
30kts. Overall, this setup is conducive for the potential of a few 
strong to severe storms. Winds will be the primary threat, however, 
sfc-1km shear between 15 to 20kts and 0-3km CAPE around 150-180J/kg 
mean that a few weak and brief tornados are also in the realm of 
possibility... especially if any semi-discrete cells can develop. 
Isolated instances of flash flooding could also be possible as a few 
locations have had enough rainfall in the short-term that 1hr FFG 
has fallen to 1.3-1.5 inches, but overall not strong enough of a 
threat to warrant any sort of watch. These threats will exist 
through about 10pm this evening. 

While we may not stay completely dry, the focus during the overnight 
period will transition to strong gusty winds in the mountains and 
adjacent foothills as the low-level jet swings across the southern 
Appalachians. Have decided to hoist a Wind Advisory from Blount 
through Unicoi as HREF probabilities of wind gusts GTE to 40mph have 
increased to around 50-70%. 

Some additional scattered activity is expected as weak impulses 
continue to traverse mean flow Saturday, however, shear and 
instability profiles will be even less favorable for strong to 
severe storms. Ultimately, this pattern will continue for much of 
the period as daily chances of showers and thunderstorms are 
forecast through Friday. Timing and strength of convection is very 
uncertain as it will depended on how exactly the small disturbances 
evolve with time. 

&&

.AVIATION...
(18Z TAFS)
Issued at 109 PM EDT Fri May 22 2026

Showers and storms will move into the region later this afternoon
through the evening hours with the most significant impacts likely
to be at CHA and TYS where low MVFR is expected. TRI's reductions
will be later into the evening and potentially not as significant
as the other two sites. Overnight, rain coverage will decrease
with MVFR likely to linger at CHA. Another impact will be LLWS due
to winds around 2,000 feet AGL reaching or exceeding 30 kts. This
is most noted at CHA and TYS, so LLWS was introduced. This will
decrease after sunrise with another increase in rain chances. 

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             65  81  64  83 /  80  80  60  80 
Knoxville McGhee Tyson Airport, TN  65  80  63  83 /  90  80  70  80 
Oak Ridge, TN                       63  79  61  83 /  90  80  70  80 
Tri Cities Airport, TN              61  80  60  83 /  80 100  60  80 

&&

.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...Wind Advisory from 8 PM this evening to 8 AM EDT Saturday for 
     Blount Smoky Mountains-Cocke Smoky Mountains-Sevier Smoky 
     Mountains-Southeast Greene-Unicoi.

VA...NONE.
&&

$$

DISCUSSION...KRS
AVIATION...BW


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