textproduct: Morristown

KEY MESSAGES

Updated at 200 PM EDT Wed Sep 2 2026 - Very hot conditions are expected through the rest of the week with highs reaching well into the 90s and heat index values approaching or exceeding 100 for most places outside the higher elevations.

- Temperatures will gradually moderate some through the weekend with a return of isolated to scattered showers and storms.

- A few storms Friday afternoon/evening mainly north and then including the remainder of the area Saturday may become strong to severe, with damaging wind gusts the primary threat.

DISCUSSION

Issued at 200 PM EDT Wed Sep 2 2026

No significant changes with the weather forecast, with the heat being the main story. A large ridge parked over the region will keep things quite hot through Friday. Temperatures this afternoon and tomorrow will be at least flirting with, and possibly reaching or exceeding, record highs both afternoons. Friday will still be quite hot, but may be just a bit further off the slightly higher daily records. Heat index values will approach or exceed 100 over nearly all of our area outside of the higher elevations, with many locations especially south and central will have heat index values top out at or above 105. A heat advisory is in effect for the southern valley today and this will be extended until Friday evening. Will also add a heat advisory for portions of the central valley and northern Plateau for Thu afternoon until Friday evening.

Daily Record High Maximum Temperatures

Date Chattanooga Knoxville Tri-Cities Oak Ridge 09-02 100(2011) 98(2011) 96(1943) 99(1953) 09-03 100(1954) 98(2011) 96(2011) 99(2011) 09-04 102(1954) 101(1954) 99(1954) 100(1954)

By this weekend the upper ridge axis will shift to our west as a trough deepens over the northeastern CONUS with a return to more northwesterly flow aloft, taking the edge off of the oppressive heat as we head through the weekend into early next week. While we will back off of the records it will still be hot, and we will also see an uptick in isolated to scattered showers and thunderstorms even outside of the higher terrain especially Saturday through Monday.

Models generally show a weak surface boundary sagging south toward us Friday and then across our area Saturday. CAPE will increase with some steepening of the mid level lapse rates Friday afternoon north and then across the remainder of our area Saturday ahead of the weak boundary, with significant DCAPE likely to be present as well. Shear should remain weak, but a few storms may become strong to severe with damaging wind gusts the primary threat Friday afternoon/evening mainly north and then including the remainder of our area Saturday.

The ridge is forecast to build back over the region for Tuesday and Wednesday of next week, but there is some uncertainty in the models on the strength and placement of the ridge. The ensembles paint slightly different pictures, with the EPS/EPS-AIFS camp showing a stronger ridge over us which would likely bring a return to very hot conditions, and the GEFS camp showing a more muted ridge. Either way it will remain hot, but we will have to wait to see if the more oppressive heat will be returning next week.

AVIATION

(18Z TAFS) Issued at 1247 PM EDT Wed Sep 2 2026

Mostly a persistence forecast, so will include fog again at TRI late tonight. Otherwise, a VFR forecast for the period all sites. Winds will generally be light.

PRELIMINARY POINT TEMPS/POPS

Chattanooga Airport, TN 75 100 75 99 / 0 10 10 0 Knoxville McGhee Tyson Airport, TN 73 98 73 97 / 0 10 10 10 Oak Ridge, TN 73 98 73 98 / 0 10 10 10 Tri Cities Airport, TN 68 96 68 95 / 0 10 10 10

MRX WATCHES/WARNINGS/ADVISORIES

NC...NONE. TN...Heat Advisory from 1 PM Thursday to 8 PM EDT Friday for Anderson- Campbell-Knox-Morgan-North Sevier-Northwest Blount-Scott TN- Union.

Heat Advisory until 8 PM EDT /7 PM CDT/ Friday for Bledsoe- Bradley-Hamilton-Loudon-Marion-McMinn-Meigs-Northwest Monroe-Rhea-Roane-Sequatchie-West Polk.

VA...NONE.