


Area Forecast Discussion
Issued by NWS Greer, SC
Issued by NWS Greer, SC
087 FXUS62 KGSP 100603 AFDGSP Area Forecast Discussion National Weather Service Greenville-Spartanburg SC 203 AM EDT Thu Jul 10 2025 .SYNOPSIS... The active summertime weather will continue thru the end of the week and into the weekend with scattered to numerous showers and thunder- storms each day. Temperatures will increase again over the weekend and early next week as an upper ridge amplifies. && .NEAR TERM /THROUGH TONIGHT/... As of 150 AM Thursday: Convection still ongoing across portions of the area early this morning. Expect this activity to dissipate/move east before daybreak. Brief heavy rainfall will continue to be possible in any storms that move through. Low clouds and patchy fog develop across much of the area by daybreak then scatter out before noon. Expect another round of diurnal convection today with a little later start than usual. CAMs show a line of convection developing over the mountains and moving south and east across the area through late afternoon and moving out/dissipating by mid evening in response to a short wave moving in from the west. Coverage overall looks to be less than Wednesday, but enough for likely PoP. The atmosphere becomes moderately unstable but but bulk shear remains 20 kts or less. Forecast soundings show a moist profile but with some DCAPE while CAPE profiles look tall and thin. Expect only the chance for isolated wet microbursts in the stronger storms due to lack of organization or strong cold pool development. There also looks like less of a chance of training or merging cells, but isolated areas of heavy rainfall will again be possible. Isolated flooding could result, especially if heavy rainfall occurs over areas that saw heavy rain Wednesday. Fog and low clouds will return for at least a portion of the area overnight. Highs will be near normal with only a smattering of heat index values near 100 over the Lakelands. Lows tonight will be near to slightly above normal. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... As of 1:15 AM EDT Thursday: The short-term fcst picks up at 12z on Friday with broad upper ridging still in place to our east and west. Numerous, weak upper impulses are expected to translate over our area and just to our north thru the period. This energy will likely provide at least some amount of upper support for convection each day. At the sfc, we will remain under the western periphery of the Bermuda High thru most of the period. This will keep moist, SWLY low-lvl flow over our area thru early Sunday. On Sunday, most of the latest model guidance has the Bermuda High retreating eastward with our winds taking on more of a WLY to NWLY component from the weak high pressure to our NW. We can expect active weather each day with sct to numerous showers and thunderstorms each afternoon and evening, with the best coverage generally expected over the mtns. The persistent moist/active pattern suggests a continued risk for areas of excessive rainfall and localized flooding each day. Model profiles continue to support some strong to severe storms each day as well. High temperatures are expected to be a few degrees above-normal each day. Heat indices should remain below Advisory criteria thru the period. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... As of 12:45 AM EDT Thursday: The extended period picks up at 12z on Sunday and is expected to remain fairly active. It`s looking like the Bermuda High will retreat somewhat early in the period, with low-lvl flow across our area losing its persistent SWLY component. Weak sfc high pressure to our NW will likely keep more of a light, NLY wind over our CWA into Tuesday. Nonetheless, sfc winds will likely end up being light and vrb during much of this period. By Wednesday, most of the long-range guidance has the Bermuda High expanding westward again with low-level flow favoring a SLY to SWLY direction over the western Carolinas thru day 7. Aloft, numerous weak shortwaves will move across the OH and TN valleys and over the central and southern Appalachians over the weekend and early next week. This energy aloft will help support above-climo PoPs over the mtns and near-climo PoPs outside the mtns on Sunday and Monday. From Tuesday onward, diurnal PoPs increase to likely across most of our fcst area. At this time, there doesn`t appear to be a significant severe wx threat any particular day, with isolated strong to severe thunderstorms possible each day. With the moist airmass expected to persist over our region thru the period, the bigger threat will likely be excessive rainfall from showers and thunderstorms that could produce localized flooding. Otherwise, high temperatures are expected to remain about a category above normal on Sunday and Monday, with values being closer to normal for the rest of the period. Dewpts are expected to re- main low enough to keep heat indices below Heat Advisory criteria (ie, 105 degrees) although some values between 100 and 105 are possible over our southern Upstate and Piedmont zones on Sunday and Monday. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... At KCLT and elsewhere: Convection still ongoing for portions of the area so have TEMPO for TSRA where chance is highest. Once convection ends, most guidance is still on board with MVFR stratocu and IFR stratus developing before daybreak. MVFR to IFR fog, LIFR at KAVL, also expected with lower conditions possible. Clouds should scatter out before noon. Expect another round of diurnal convection today with initiation a little later than normal. Coverage shouldn`t be as high as Wednesday, so just have PROB30 for now. Convection lingers into early evening then moves east with VFR. Light and variable wind outside of lingering convection early this morning picks up from the SW, NNW at KAVL, during the day. Winds go light later in the evening. Outlook: Typical summertime weather is expected into early next week, with scattered to numerous thunderstorms mainly in the afternoon/evening and fog and/or low stratus possible each morning. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...None. NC...None. SC...None. && $$ SYNOPSIS...JPT NEAR TERM...RWH SHORT TERM...JPT LONG TERM...JPT AVIATION...RWH