FXUS64 KMRX 221809 AAA AFDMRX Area Forecast Discussion...UPDATED National Weather Service Morristown TN 209 PM EDT Sat Aug 22 2026 ...New AVIATION... .KEY MESSAGES... Updated at 127 PM EDT Sat Aug 22 2026 - This afternoon and evening, isolated to scattered showers and storms are expected in Northeast Tennessee, Southwest Virginia and the East Tennessee Mountains. - Sunday and Monday will be dry with rain chances returning midweek. && .UPDATE... Issued at 728 AM EDT Sat Aug 22 2026 Published a small update a brief bit ago to add fog into the early morning sunrise period and to expand the area of low rain and storm chances for later this afternoon and early evening after seeing the new day 1 forecast from the Storm Prediction Center. Coverage south of Interstate 40 is likely to be very isolated, if anything occurs at all, but cannot rule out the chance for a strong to severe wind gust given the dry air aloft. && .DISCUSSION... Issued at 203 AM EDT Sat Aug 22 2026 In the upper levels, a trough is over the Ohio Valley, extending down to Florida. At the surface, a stationary boundary is over North Georgia. Showers and storms have mostly dissipated for the rest of the night. In the early morning hours, clearing skies will lead to fog development near bodies of water and low-lying areas. Patchy dense fog will be possible in the early morning hours. A cold front will approach the region this afternoon and evening, bringing isolated to scattered showers and storms in Northeast Tennessee, Southwest Virginia and the East Tennessee Mountains. Elsewhere, will be mostly dry but some isolated activity will be possible. Some of the CAMs have come in wetter for today this cycle than last cycle, I think the timing of the cold front is lining up better with max heating. A few strong storms, possibly even severe can't be ruled out. The front will move through this evening bringing cooler temps and lower dew points tonight and tomorrow. Sunday dew points will be in the 60s and highs will be in the 80s (Chattanooga area may hit 90). Sunday and Monday will be dry with high pressure at the surface. The upper level pattern will be about the same with a deep trough on the East Coast and a ridge centered over the Rockies. The NBM has low rain chances Tuesday increasing to 30-40% chances by Wednesday. The trough will be centered over the Ohio Valley again by midweek with at least one shortwave rotating through the pattern Wednesday night or Thursday. && .AVIATION... (18Z TAFS) Issued at 127 PM EDT Sat Aug 22 2026 At least some ISOLD SHRA/TSRA are expected in East Tennessee this afternoon, with a little better coverage expected with an additional round of convection tonight just along/ahead of an incoming front. KTRI stands the best chance of seeing SHRA/TSRA but even that's not certain. Have PROB30 groups in at KTRI and KTYS to handle things. KCHA seems less likely to see any convection. The last item of note is there could be some fog development later tonight but uncertainty in how quickly clouds clear out preclude mentioning that in the TAFs for the moment. KTRI would be the most likely to see it if it occurs. && .PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 93 68 90 64 / 0 20 0 0 Knoxville McGhee Tyson Airport, TN 90 65 86 62 / 20 30 0 0 Oak Ridge, TN 90 63 86 60 / 20 30 0 0 Tri Cities Airport, TN 84 62 81 56 / 40 40 0 0 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$ DISCUSSION...McD AVIATION...CD