FXUS62 KGSP 051819 AFDGSP Area Forecast Discussion National Weather Service Greenville-Spartanburg SC 219 PM EDT Wed Aug 5 2026 .WHAT HAS CHANGED... No significant changes with this forecast package. Updated the aviation discussion for the 18z TAFs. && .KEY MESSAGES... 1. Above-average rain chances and below-normal temperatures continue the rest of the week and into the weekend. Isolated flash flooding will be possible across the area each day through Saturday. 2. A return to seasonably hot conditions and typical coverage of afternoon and evening showers and storms is expected starting Sunday and continuing through early next week. && .DISCUSSION... Key message 1: Above-average rain chances and below-normal temperatures continue the rest of the week and into the weekend. Isolated flash flooding will be possible across the area each day through Saturday. A weak upper low that has been spinning invof northern GA is finally starting to open up into a weak trough that will linger just to our west. The trough will be reinforced/merged with a digging longwave trough over the Northern Plains to the Great Lakes on Saturday. This will combine with a persistent Bermuda High to keep a deep-layered SWLY flow and elevated PWATs atop the forecast area thru the end of the week. Moist profiles and weak shear will keep severe thunderstorms chances low. However, efficient rain rates and slow storm motions will lead to an isolated flash flood threat from this aftn thru Saturday, mainly during the typical peak-heating/diurnal cycle. Highs will be a category or two below normal under plenty of cloud cover and lows near to slightly above normal. Key message 2: A return to seasonably hot conditions and typical coverage of afternoon and evening showers and storms is expected starting Sunday and continuing through early next week. Large subtropical upper ridge starts to build west from the Atlantic over the Southeast states Sunday into Monday, then becomes flattened by upper troughing over the Great Lakes to the Mid-Atlantic by the middle of next week. This will bring low-level flow more out of the west to west-northwest and usher in slightly drier air into the region. Overall, temps will return to normal Sunday and a couple degrees above normal Monday thru midweek. Diurnal convection should return to near typical early-mid August levels, with scattered to numerous in the mountains and isolated to widely scattered elsewhere. A few pulse severe storms and localized heavy rain will likely be a threat each day. The muggy conditions will result in heat indices pushing into the upper 90s to lower 100s each aftn across most of the Piedmont. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... At KCLT and elsewhere: Widespread showers with some embedded general thunderstorms have developed across the mountains and western Upstate, with more isolated coverage so far to the east. Given the environment, expect coverage to peak late aftn into early evening. Will go with VCSH and TEMPO TSRA at all sites, except PROB30 at KCLT, where confidence is lower. Convection should wane by late evening. Very moist air mass in place will set up another night of stratus and fog development across the area. Guidance generally agreement on widespread low-MVFR to IFR cigs around or slightly before daybreak, with areas of fog in the mountain valleys, patchy fog across the Piedmont. Stratus will gradually lift and scatter to VFR again late morning to early aftn on Thursday. Similar, if not greater, coverage of showers and thunderstorms expected Thursday aftn. Will add a PROB30 for KCLT, given the high confidence. Winds will be light, mainly out of the south, except VRB around thunderstorms. Outlook: Scattered to numerous diurnal showers and thunderstorms expected each day thru early next week, with associated flight restrictions. Patchy fog and low stratus will be possible each morning, especially in the mountain valleys and anywhere that received significant rainfall the previous day/evening. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...None. NC...None. SC...None. && $$ ARK