Area Forecast Discussion
Issued by NWS Knoxville/Tri Cities, TN
Issued by NWS Knoxville/Tri Cities, TN
576 FXUS64 KMRX 201743 AFDMRX Area Forecast Discussion National Weather Service Morristown TN 1243 PM EST Thu Nov 20 2025 ...New DISCUSSION, AVIATION... .KEY MESSAGES... Updated at 1229 PM EST Thu Nov 20 2025 - Above normal temperatures expected through the first half of next week. - There will be showers and a few thunderstorms around at times today through Saturday, then drier weather Sunday and Monday before additional rain chances arrive Tuesday. && .DISCUSSION... Issued at 1229 PM EST Thu Nov 20 2025 A weak surface front is located across our southern sections today, marked by a dewpoint gradient between CHA and TYS along with a few light showers, and will gradually lift northward through the evening and overnight hours. Isentropic lift has been mainly in Middle TN today, but that lift will shift east tonight, bringing an area of showers to our area. Models show some weak elevated instability, so a few rumbles of thunder may occur overnight, mainly near the Cumberland Plateau. There will likely be a lull in the precipitation early Friday as the front lifts just north of our area, but a weak upper level short wave trough approaching from the west will bring another round of showers and a slight chance of thunderstorms late Friday and Friday night. Again, instability looks to be weak but enough to warrant a slight chance of thunderstorms being mentioned in the forecast. The surface cold front and main upper trough axis will move through our area on Saturday. Forecast wind profiles look stronger with some shear present, and slightly higher (but elevated) CAPE. Early morning timing of showers will limit severe potential, but some strong storms with gusty winds and heavy rain may be possible. There will not be any strong push of colder air into the region behind the front, so temperatures will remain warmer than normal through the weekend into early next week. Dry conditions area likely Sunday and Monday as a ridge builds over the region, then another system will bring a chance of rain in the Tuesday/Wednesday time frame. A surge of colder air may arrive in the area in time for Thanksgiving. && .AVIATION... (18Z TAFS) Issued at 1229 PM EST Thu Nov 20 2025 CHA has been slow to lift from LIFR conditions, and timing any improvement will be a low confidence attempt. There are some obs in N AL/GA that are lifting to MVFR, so the CHA TAF will go that route after 20Z. Rain showers will spread into the area overnight at all sites, lowering vis/cigs again to at least MVFR. Moist conditions after the rain exits will continue to keep IFR/MVFR cigs through the end of this TAF period. && .PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 61 74 62 74 / 40 50 80 30 Knoxville McGhee Tyson Airport, TN 61 72 61 69 / 70 50 90 50 Oak Ridge, TN 60 71 60 68 / 70 60 90 50 Tri Cities Airport, TN 55 67 57 64 / 80 80 80 60 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$ DISCUSSION...DGS AVIATION...DGS