616
FXUS64 KMRX 172329
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
729 PM EDT Thu Sep 17 2026

...New AVIATION...

.KEY MESSAGES...
Updated at 722 PM EDT Thu Sep 17 2026

- Hot. Will become less hot next week. Drink plenty of water and
  find shade when possible when outdoors, especially in large
  outdoors sports venues.

- Increasing rain chances for the higher terrain this weekend into
  next week with the valley less likely to see rain, similar to a
  typical summer pattern.

&&

.DISCUSSION...
Issued at 322 PM EDT Thu Sep 17 2026

As of this writing there are large cumulonimbus clouds in southwest
Virginia and southern Kentucky producing showers and a few
thunderstorms. A few gusty winds are possible with these storms,
paired with lightning. A change of pace from the absolutely
suppressive ridge we`ve had the last few days that stymied any
activity.

Speaking of the ridge, the heat dome of doom, I mean the large and
in charge pile of hot air, it is gradually shifting its central axis
west towards Arkansas. As a consequence we`re getting enough
moisture now filtering in to begin sparking a few showers and
thunderstorms where the oppressiveness and dry air has lessened
enough. Today that`s southern Kentucky and southern Virginia,
maybe a spot or two in Tennessee. As we head into the weekend and
early next week, and the ridge continues its two step to the left,
this area will expand to the whole of the area and everyone will
have a shot for a thunderstorm or two. Not everyone will get rain
though, we`re still in a summer pattern so its still hit or miss
style. Next week we`ll look to the Midwestern weather pattern to
see if a forecast trough can spark better storm coverage down here
between Monday and Wednesday, primarily during the afternoon
hours still. For now not expecting severe storms, but any decent
thunderstorm could pack brief gusty winds inside the core.

Tracking Chattanooga`s consecutive 90F record, next Wednesday`s
forecast high is 89, and the day after is 87. So perhaps an end is
in sight for the worst of the heat.

&&

.AVIATION...
(00Z TAFS)
Issued at 722 PM EDT Thu Sep 17 2026

The few showers and storms that developed this afternoon have
mostly dissipated. Tomorrow will be similar with the best chance
for showers and storms near TRI in the late afternoon and early
evening hours. In the early morning hours, brief morning fog will
be possible at TRI right around sunrise.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             74  98  74  98 /  10  10   0  40
Knoxville McGhee Tyson Airport, TN  72  95  71  94 /  10  20  20  30
Oak Ridge, TN                       71  95  71  93 /  10  20  10  30
Tri Cities Airport, TN              68  89  67  88 /  20  50  20  40

&&

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

$$

DISCUSSION...Wellington
AVIATION...McD