Area Forecast Discussion
Issued by NWS Knoxville/Tri Cities, TN
Issued by NWS Knoxville/Tri Cities, TN
642 FXUS64 KMRX 232320 AFDMRX Area Forecast Discussion National Weather Service Morristown TN 720 PM EDT Sat Aug 23 2025 ...New AVIATION... .DISCUSSION... Issued at 135 PM EDT Sat Aug 23 2025 Key Messages: 1. Scattered showers and embedded thunderstorm through this evening with showers continuing. Localized flash flooding is possible through this evening. 2. Strong frontal boundary moves through Sunday. Scattered showers and possibly embedded thunder again. 3. Much cooler, pleasant and dry conditions for much of next week. Discussion: SPC meso-analysis shows MLCAPES of around 1000 with DCAPES near 600. Little to no shear. A theta-e ridge axis is evident over the Plateau along a surface trough axis. PWs are near 1.8 inches along this axis. If training of showers occur, localized flash flooding is possible. Conditions are not favorable for severe storms but isolated gusts up to 40 mph possible. REFS and HREF show the greatest coverage of showers and storms across the Plateau, central Tennessee valley and southwest Virginia through this evening. A slow moving 925mb/Surface front-genetic forcing remains across the region through Sunday. Strong cool front will move across the region late tomorrow moving the theta-e ridge axis east of the area. Until then scattered to occasional widespread showers and embedded thunder will remain. For Monday through next Saturday, ensemble cluster analysis and deterministic models show a deep upper trough over the eastern third of the nation. Below normal temperatures. much drier airmass, and mostly dry conditions are expected. NBM probabilities show low chance of showers across southeast Tennessee for late Tuesday and Tuesday night. Latest deterministic GFS depicts showers as well but confidence is too low to include in the forecast. && .AVIATION... (00Z TAFS) Issued at 718 PM EDT Sat Aug 23 2025 PROB30 for MVFR conditions exist at all sites through midnight due to ongoing showers and storms. A mix of IFR and LIFR expected overnight due to fog and low ceilings. Additional showers and storms expected toward sunrise and through the end of the period, which may bring additional periods of MVFR conditions. && .PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 69 87 63 82 / 60 20 0 0 Knoxville McGhee Tyson Airport, TN 69 85 62 80 / 60 30 0 0 Oak Ridge, TN 68 85 59 79 / 70 30 0 0 Tri Cities Airport, TN 66 82 59 77 / 50 40 10 0 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$ DISCUSSION...DH AVIATION...