Area Forecast Discussion
Issued by NWS Greer, SC
Issued by NWS Greer, SC
238 FXUS62 KGSP 091719 AFDGSP Area Forecast Discussion National Weather Service Greenville-Spartanburg SC 119 PM EDT Wed Jul 9 2025 .SYNOPSIS... Hot and humid conditions will cool closer to normal late this week with numerous afternoon and evening showers and thunder- storms expected each day. Temperatures increase again over the weekend and early next week as an upper ridge amplifies. Mainly afternoon and evening showers and thunderstorms will continue each day. && .NEAR TERM /THROUGH THURSDAY/... As of 1145 AM Wednesday: Mid day water vapor satellite imagery depicts a northern stream trough over the Great Lakes Region with a broad Bermuda high nudging into the Coastal Plain. A deep plume of moisture has been drawn north across the area with PWATs ranging from 1.6" over the mountains to just over 2" east of I-77. A cumulus field has begun to develop across the area with the most agitated cumulus over the mountains where several deeper updrafts have initiated convection across the higher elevation ridges. Weak height falls and at least some degree of synoptic forcing from the Great Lakes wave interacting with a warm and humid airmass will foster numerous to widespread diurnal thunderstorms this afternoon into the evening hours. The greatest coverage is expected to be across North Carolina with some activity extending down into the Upstate and northeast Georgia as well. With time, convection will likely become loosely organized along composite cold pools with several multicell clusters and linear segments. The environment will be marginally supportive for severe weather with 3000-4000 J/kg of surface-based CAPE, modest DCAPE around 800 J/kg and average vertical totals in the mid to upper 20s. This returns low-end microburst composite values in the 3-5 range, which typically corresponds with an average summer microburst threat and the potential for a handful of severe thunderstorms. In addition, plentiful moisture and the potential for a couple slow moving/training storms may result in a couple isolated instances of flash flooding, especially in any urban areas such as the Charlotte metro. A quick 1-3" of rain will be possible under any torrential downpours. A few storms may linger through the evening, but activity should dissipate/push out of the area by late evening with a rather quiet overnight period expected. Patchy fog cannot be ruled out for any location that experiences heavy rain, especially the mountain valleys. Another busy convective day is on tap for tomorrow as broad troughing extends down the spine of the Appalachians as the parent northern stream wave slowly shifts out of the Great Lakes and into New England. A continued warm and humid environment will once again support the development of numerous to widespread diurnal thunderstorms. The environment will be similar to today with loosely organized convective clusters along cold pools in a marginal environment for wet microbursts. Isolated flash flooding will be possible as well, especially if heavy rainfall occurs over areas that see heavy rain today. && .SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/... As of 12:15 PM EDT Wednesday: Mid level ridging will build over the area late in the week into Saturday. This will lead to a decrease in pops from today and Thursday. However due to moisture caught under the ridge there will continue to be higher than climo pops. The highest pops will be over the mountains each afternoon and evening. Highs on Friday will be near climo increasing to a few degrees above climo on Saturday. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... As of 12:25 PM EDT Wednesday: Mid level ridging will remain in place for Sunday into early next week leading to typical mid July conditions. High temperatures are expected to be a few degrees above normal each day with heat indices around 100-103 in the Piedmont region. An active mainly diurnally driven convective pattern will continue with the highest pops each day in the mountains. && .AVIATION /17Z WEDNESDAY THROUGH SUNDAY/... At KCLT and elsewhere: A busy TAF period will continue across the area with multiple periods of restrictions for a myriad of hazards expected. First up will be afternoon and evening thunderstorms that are starting to spread in coverage across the mountains. Numerous to widespread storms are expected through the remainder of the afternoon and into this evening. Associated visibility and ceiling restrictions will accompany these storms. Heading into tonight, widespread low stratus along with patchy fog appears like a good bet given plentiful moisture and wet ground from today`s storms. MVFR to IFR visiblity and ceiling restrictions can be expected with a few instances of LIFR not out of the question. Morning fog and stratus will mix out/scatter after sunrise with a brief return to VFR through the rest of the morning. Another busy day of storms is on tap again for tomorrow afternoon. Outlook: Typical summertime weather is expected into the weekend, 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...DEO NEAR TERM...TW SHORT TERM...SCW LONG TERM...SCW AVIATION...TW