761 FXUS62 KGSP 100659 AFDGSP Area Forecast Discussion National Weather Service Greenville-Spartanburg SC 259 AM EDT Tue Jun 10 2025 .SYNOPSIS... A cold front moving thru the area today will produce scattered showers and thunderstorms. Most areas will see quiet weather and lower humidity Wednesday behind the front. Seasonably hot and humid weather returns late in the week with numerous showers and storms each afternoon and evening. && .NEAR TERM /THROUGH TONIGHT/... As of 146 AM Tuesday: Early morning water vapor imagery depicts a closed and vertically stacked upper low spinning over the Great Lakes region with a trough axis extending just east of the Mississippi River. Surface observations along with low-level ThetaE fields place a cold front draped from eastern Kentucky to central Tennessee. A complex of deep convection also resides across the coastal plain and will continue to shift farther east of the area through daybreak. The rest of the pre-dawn hours will remain quiet with no radar returns across the area, although a few isolated sprinkles or light shower cannot be ruled out mainly along the Tennessee border. A few instances of patchy fog will also be possible, especially in favorable mountain valleys as well as in the foothills along the I-40 corridor. While a couple pockets of dense fog could be realized, coverage isn`t anticipated to be enough to warrant a dense fog advisory. Heading into the daylight hours, any pockets of fog will quickly mix out following sunrise with low stratus also lifting and scattering. The previously mentioned upstream cold front will swing across the area today with timing around peak heating. Sufficient forcing for ascent coupled with modest instability will support the development of a broken band of convection along the advancing boundary. Coverage should remain scattered for much of the area, but several CAM members hint at the potential for a more solid linear segment to fill in across the North Carolina foothills and push into the I-77 corridor. A couple strong storms with gusty winds will be possible and an isolated severe storm with locally damaging winds cannot be completely discounted if a more solid line with a balanced cold pool is able to get cranking. The best chance for any isolated severe storms will be generally along and east of I-77. Convection will shift east of the area by this evening with a quiet post frontal night expected. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... As of 115 AM Tue, key messages: 1. Cold front stalls to our south Wednesday. Convection looks to be suppressed over most of the CWA that day in the drier air north of the front and weak subsidence aloft. 2. The front reactivates Thursday and convective chances tick upward a bit. These chances linger into early Friday, as elevated showers or storms remain possible in the frontal zone. 3. Max temps trending gradually warmer over the short term period. Shortwave axis will drift across the Carolinas/Georgia during the day Wednesday. Weak high pressure will spread over the CWA behind that and the sfc front; flow in the mid to upper levels will be W to NW but weak enough downslope may not be much of a factor, and low-level flow may remain light SW`ly. Prog soundings are dry aloft and a slight midlevel subsidence inversion remains through the day. The axis of the shortwave may interact with the front to promote some convective development along it, so isolated precip is not out of the question in our far SE nearest the front, and a stray shower over the mountains can`t be entirely ruled out although not necessarily worthy of PoPs. The front begins to reactivate Wed night or early Thu as shortwave moves thru TX and toward the lower MS Valley, promoting southerly flow across the Southeast. Profiles moisten enough in the layer above the PBL to make deep convection plausible over most of the area by the diurnal peak. Winds are weak through most of the column and thus shear will be very weak. Surface to midlevel delta-theta-e is marginal at around 20 K, but DCAPE approaching 1000 J/kg suggests a few storms could pose a risk of a damaging microburst Thu aftn/evening. A few hundred joules of MUCAPE persists Thursday night so some overnight showers/storms are possible; continued moisture return suggests wind threat will decrease while threat of locally heavy rain will increase, with storm motion remaining slow owing to the weak environmental flow. && .LONG TERM /FRIDAY THROUGH MONDAY/... As of 200 AM Tue, key messages: 1. Subtropical humidity returns to the area by Friday, which essentially remains in place through the remainder of the period; temps remain near normal. 2. Moist profiles and weak shear persist, supporting a typical June threat of diurnally driven wet microbursts producing localized heavy rainfall and perhaps a few instances of damaging wind. 3. A weak cold front may impinge on the area Monday or early Tuesday, but confidence is low and airmass change appears unlikely. Between the MS Valley shortwave and the Bermuda High, the warm front continues to shift northward Friday and steady S to SW persists over the CWA. This return flow continues through the weekend, and dewpoints will be in the upper 60s to lower 70s over most of the Piedmont each afternoon. The atmospheric column approaches saturation over a deep layer; PWATs trend gradually higher each day through Sunday, although values look likely to remain relatively tame at only 1.3 to 1.5 SD above climo per ensembles. PoPs are higher than climo, chance Piedmont and likely mountains on Friday, and likely to categorical Sat and Sun. 0-3km and 0-6km shear remain weak and storm motion should remain slow. DCAPE and theta-e lapses look marginal for a severe wind threat, although the weak shear and high PWATs are classic for June. Wet microbursts producing torrential rain and isolated instances of damaging wind still look possible each day thru Sunday. Temps will be near normal, so despite the humidity Heat Index should top out only in the mid 90s. The seasonably hot, humid weather and mainly diurnal PoPs most likely will repeat on Monday, but confidence diminishes a bit with models still not in agreement on the progression of the trough out of the MS Valley. This could carry a frontal boundary across the Appalachians late Mon or early Tue, mainly serving to focus convection and perhaps increase shear. The 12/18z ECMWF runs suggested a backdoor front might instead push down the East Coast although probably not bringing cooler or less humid air to the CWA until after the end of the period, if at all. The forecast continues to reflect humid and stormy weather Monday, not much different from Sunday, but that could change one way or the other on subsequent forecasts. && .AVIATION /07Z TUESDAY THROUGH SATURDAY/... At KCLT and elsewhere: Low stratus and patchy fog will be the immediate focus through the rest of the early morning hours. Several MVFR to IFR ceiling observations have started coming in mainly south of I-85 and near the Charlotte area. MVFR to IFR ceilings should become common through daybreak along and south of the I-85 corridor. Patchy fog will also be possible, especially across mountain valleys and in the foothills along the I-40 corridor (KAVL/KHKY). Any patchy fog should mix out following sunrise along with lifting and scattering of the low stratus deck. Cloud bases will remain low, however, and brief periods of MVFR ceilings may continue into the early afternoon before the stratus fully scatters. Thereafter, scattered showers and thunderstorms will be possible along an advancing cold front, especially along the I-85 corridor. PROB30 groups have been carried at all terminals for brief visibility and ceiling restrictions. VFR is expected to return this evening as any storms depart the area. Outlook: VFR should continue through Wednesday. Mainly diurnal thunderstorms return Thursday and will persist each afternoon/evening into the weekend. There will be potential for late night and early morning fog and low stratus restrictions each day. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...None. NC...None. SC...None. && $$ SYNOPSIS...Wimberley NEAR TERM...TW SHORT TERM...Wimberley LONG TERM...Wimberley AVIATION...TW