textproduct: Morristown

KEY MESSAGES

Updated at 722 PM EDT Mon Oct 26 2026

- Dry weather will continue over the forecast period with cool mornings and mild afternoon highs.

- Low relative humidity values in the 30s to low 40s are also expected through at least Tuesday, but likely beyond. Winds will be light however, so fire weather concerns remain low.

- Rainfall returns this weekend, but likely holds off until Sunday before it does.

DISCUSSION

Issued at 1250 PM EDT Mon Oct 26 2026

The main concerns for the forecast period are dry afternoon RH values today and tomorrow, and the eventual return of rain chances to the area this weekend.

A strong and resilient upper ridge will remain anchored over the central Gulf coast for the next 24 to 36 hours or so, before weakening and being shunted further south into the Gulf and perhaps Florida to some extent by shortwaves ejecting eastward from the Pacific NW and a large scale trough moving through eastern Canada.

Regarding the afternoon relative humidity values, NBM guidance continues to be too high with afternoon dewpoints. Blended in a healthy dose of CONSShort guidance into this afternoon, and tomorrow's, dewpoint forecasts. The result is forecast MinRH values in the 35-45 percent range across the CWA which seems reasonable. Fire weather concerns remain low however, despite the low RH values, as high pressure and light winds will remain in place. I wouldn't expect drastically different conditions on Wednesday either, but with the ridge breaking down and slightly higher PWATs in place the afternoon RH should be a touch higher.

Attention then turns to this weekend. On Friday a fairly potent shortwave will begin to lift NE out of Texas and move into Kentucky and the lower Ohio valley during the weekend. While the amplitude of the upper ridge will have been knocked down by that time, we'll still have surface and H85 ridging in place as this system approaches. Given a cutoff low remaining over the Pac NW and a slow moving subtropical jet off the coast of the Baja, I would expect that timing will continue to be the main source of uncertainty here and that the eventual solution will be slower than at least some deterministic guidance shows. For example, the GFS shows rain chances returning to the area by Sat afternoon while the ECMWF keeps us dry into Sunday before rain returns. AI guidance seems to side with the drier side of the deterministic runs, and I would tend to lean that direction as well. Sunday seems much more likely to be when widespread rain finally moves back in.

AVIATION

(00Z TAFS) Issued at 722 PM EDT Mon Oct 26 2026

The main question overnight into the early morning will be development of fog. While fog is likely near the river valleys again, it is unclear how much will develop at the sites. A TEMPO has been added in at CHA and TRI, but confidence is limited. Otherwise, light and variable winds and limited cloud cover is expected.

PRELIMINARY POINT TEMPS/POPS

Chattanooga Airport, TN 48 76 50 75 / 0 0 0 0 Knoxville McGhee Tyson Airport, TN 46 76 49 76 / 0 0 0 0 Oak Ridge, TN 46 75 49 75 / 0 0 0 0 Tri Cities Airport, TN 42 75 45 73 / 0 0 0 0

MRX WATCHES/WARNINGS/ADVISORIES

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