textproduct: Morristown

KEY MESSAGES

Updated at 230 AM EDT Thu Sep 10 2026 - Spotty showers are possible today and tonight mainly the northern Plateau into southwest Virginia. A few rumbles of thunder will be possible. - Friday, Saturday and Sunday scattered showers and storms areawide, mainly in the afternoon and evening hours. Locally heavy rainfall is the main threat due to elevated PW values of around 2 inches.

- Above normal temperatures expected through the forecast period. If CHA hits 90 again today, they will tie the record for consecutive days with a high temp of 90 or greater. The current record is 38 days back in 1993.

DISCUSSION

Issued at 230 AM EDT Thu Sep 10 2026

In the upper levels, a weak ridge remains over the Southeast as a broad trough moves into the Midwest and Ohio Valley. At the surface, a cold front will be over the Ohio Valley today. Mostly dry weather will continue through this afternoon although a few stray showers will be possible mainly over the upper Cumberland Plateau. This evening and into the overnight hours, showers will increase, mainly in the northern third of the region as a decaying cold front slowly moves down from the north. Thunder chances are low with decreasing instability. CAMs keep showers weak but reflects better coverage across the region whereas the NBM keeps showers well to the north of Knoxville.

Daily rain chances are expected mainly in the afternoon and evening hours from Friday through the weekend. In the upper levels, a shortwave will be over the Lower Mississippi Valley. The weak surface boundary will also be lingering over or near the region through the weekend. Deep layer moisture advection is likely with high pressure over the Atlantic bringing southerly surface winds and a trough to the west bringing higher level moisture from the Gulf. Showers and storms will likely be scattered at times Friday through Saturday. NBM has the highest chances on Saturday afternoon.

The best chance for strong to severe storms will be Saturday with good instability around 2000 J/kg. With weak shear and high freezing levels the primary threat will be gusty winds. With good moisture advection, Pwat values will be elevated around 2 inches on Saturday so heavy downpours will be likely at times that may cause some isolated flooding. Steering flow around 15 knots should help keep showers and storms moving, so overall the flooding threat is low. Friday has a lower threat of impact weather with lower instability and lower Pwat values. By Sunday, the shortwave to the west is gone and a weak ridge builds into the Southeast. Therefore, showers and storms will be more isolated on Sunday and perhaps more scattered in the mountains.

Early next week, a ridge will be over the Southeast. Isolated to scattered showers and storms will be possible with the highest chances in and near the terrain. Afternoon highs will be above normal throughout the forecast period with upper 80s expected near Tri-Cities and lower 90s for Knoxville and Chattanooga areas, generally about 6 to 8 degrees above normal. Chattanooga is expected to exceed 90 degrees again today and tomorrow. If that happens, they will break the record for consecutive days with a high temp of 90 or greater. The current record is 38 days back in 1993. Saturday the forecast is 90 for Chattanooga but that may not happen if clouds and convection occur earlier in the day.

AVIATION

(06Z TAFS) Issued at 119 AM EDT Thu Sep 10 2026

VFR conditions at all TAF sites. There will be some increase in mid and high clouds with areas of broken 6-8kft ceilings at TYS and TRI from 15 to 22Z today.

PRELIMINARY POINT TEMPS/POPS

Chattanooga Airport, TN 96 72 95 72 / 0 0 40 60 Knoxville McGhee Tyson Airport, TN 93 70 93 71 / 0 10 30 30 Oak Ridge, TN 92 69 92 70 / 10 10 40 40 Tri Cities Airport, TN 87 66 87 66 / 10 20 40 10

MRX WATCHES/WARNINGS/ADVISORIES

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