textproduct: Morristown

KEY MESSAGES

Updated at 740 AM EDT Mon Jun 29 2026

- Isolated to scattered showers will continue overnight and into the morning hours mainly along and north of I-40. Another round of isolated to scattered showers and storms will be mainly confined to Northeast Tennessee this afternoon.

- Hot temperatures well into the 90s are likely this week, starting today. Heat indices will climb above 100 degrees in the Tennessee Valley especially by mid week. The central and southern valley will be right around to just below Heat Advisory criteria of 105 degrees, today. No Heat Advisory at this time but one may be needed in the following days.

DISCUSSION

Issued at 1249 AM EDT Mon Jun 29 2026

The ridge over the Southeast will strengthen today, engulfing the Ohio Valley and Great Lakes regions also. Isolated to locally scattered showers are expected overnight. Showers have been very isolated this evening. The latest CAM guidance suggests light showers will move through the Central Valley and Upper Cumberland Plateau area overnight. Showers may be tracking over the same locations that received widespread 2 to 4 inches of rain this morning. Potential for flooding overnight is low but shower development, movement and rain rates will be watched closely. PWAT values are still high just under 2 inches.

Guidance shows overnight showers dissipating in the early morning hours with another round of isolated to scattered showers setting up a little farther north between Knoxville and Tri-Cities by mid morning. Again, flooding potential is low but areas that already had a lot of rain will be more sensitive. PWAT values will be declining in the morning hours closer to 1.6 inches. Steering flow will become more northerly by morning but light showers may still train.

Isolated to scattered showers and storms will be confined mainly to Northeast Tennessee this afternoon, ending entirely in the evening.

Otherwise, this week will be hot and mostly dry as a strong ridge stays anchored over the Eastern U.S. The best chance for rain will be in the East Tennessee mountains and foothills. Generally, showers and storms will be isolated to scattered late week into the weekend. Highs today will be in the lower 90s for most of the Tennessee Valley. Heat indices will be 100 to 104 degrees, just below Heat Advisory criteria in Central and Southern Valley locations today. Tomorrow will be even warmer and a Heat Advisory may be needed with heat indices likely exceeding 105 degrees in the Central and Southern Valleys. Hot weather will continue through Saturday with highs in the mid to upper 90s and heat indices close to or exceeding the 105 degree threshold especially Wednesday and Thursday.

AVIATION

(12Z TAFS) Issued at 740 AM EDT Mon Jun 29 2026

CHA expected to continue VFR with light winds today. TYS didn't saturate all the way for fog development this morning, although some locations not far away did get fog. TRI is currently under 1/4SM and should begin to clear in the next hour or so. Very isolated chances of showers/storms from the NNW today that may pass over TRI this afternoon. Left out the chance at TYS due to uncertainty, although it's uncertain at TRI as well. Calm and mostly clear tonight with models hinting at fog again at TRI. An addition of an IFR TEMPO 07-11z there.

PRELIMINARY POINT TEMPS/POPS

Chattanooga Airport, TN 96 76 97 77 / 0 0 10 0 Knoxville McGhee Tyson Airport, TN 91 74 94 75 / 20 0 10 0 Oak Ridge, TN 92 74 95 75 / 20 0 0 0 Tri Cities Airport, TN 90 70 93 71 / 20 0 20 10

MRX WATCHES/WARNINGS/ADVISORIES

NC...NONE. TN...NONE. VA...NONE.