FXUS64 KMRX 191146
AFDMRX

Area Forecast Discussion
National Weather Service Morristown TN
746 AM EDT Tue May 19 2026

...New AVIATION...

.KEY MESSAGES...
Updated at 745 AM EDT Tue May 19 2026

- Very warm temperatures Today and Wednesday with highs roughly 10 
  to 15 degrees above normal.

- Increasing chances for showers and storms return Wednesday, with
  continued chances each day into the weekend, especially across
  the higher elevations.

&&

.DISCUSSION...
Issued at 231 AM EDT Tue May 19 2026

Mostly dry today, NBM has no POPS, but can't rule out a few isolated 
afternoon/evening showers and storms. Otherwise, very warm with 
highs in the upper 80s to near 90. Near record highs at TYS and TRI. 

On Wednesday, models still show a short-wave trough pushing the 
ridge east and opening the door for a frontal passage. Showers and 
storms will increase in coverage in response to the lower heights 
and higher moisture. Highest POPs will be across the east TN 
mountains and Cumberland plateau. REFS and LREF instability probs 
show high odds that CAPE values will be less than 1000 J/kg. Combine 
this with mid-level lapse rates of 6 degrees or less and little to 
no shear, severe storms are not expected. 

On Thursday the frontal boundary lifts north and back into the area 
and provides focus for more showers and storms. The highest POPs 
will reside along the frontal boundary. It's hard to say exactly 
where it will be within our area. Instability and shear once again 
remain limited, so no severe threat for Thursday either.   

For Friday, ridging returns and the frontal boundary lifts north 
into KY. However, plenty of moisture and instability remains so 
scattered showers and thunderstorms are once again expected.  

No real changes during the weekend into early next week period. We 
will continue to have an unsettled pattern in place with an 
environment conducive to daily showers and storms. Overall, the 
severe threat remains low during this time due to lack of shear. 

QPF through the period will be very hit or miss. Some areas may see 
several inches of rain over the next 7 days while some see far less. 
This is due to the scattered nature of the convection.

&&

.AVIATION...
(12Z TAFS)
Issued at 745 AM EDT Tue May 19 2026

VFR and dry weather expected today with generally light winds,
maybe a gust to 15 knots at TYS this afternoon. Isolated
convection post 18z to 01z or so is possible, but very low
coverage and confidence.

&&

.PRELIMINARY POINT TEMPS/POPS...
Chattanooga Airport, TN             90  68  89  66 /  10   0  70  30 
Knoxville McGhee Tyson Airport, TN  91  68  89  66 /   0   0  50  30 
Oak Ridge, TN                       89  65  87  64 /   0   0  70  40 
Tri Cities Airport, TN              89  63  87  63 /   0   0  50  50 

&&

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

$$

DISCUSSION...99
AVIATION...Wellington