Area Forecast Discussion
Issued by NWS Greer, SC
Issued by NWS Greer, SC
315 FXUS62 KGSP 121800 AFDGSP Area Forecast Discussion National Weather Service Greenville-Spartanburg SC 200 PM EDT Sun Oct 12 2025 .SYNOPSIS... A coastal low will slowly drift north along the East Coast through the first half of the week. This low will then drift offshore by midweek, as dry high pressure builds in from the west and brings above normal temperatures to our region. && .NEAR TERM /THROUGH MONDAY/... As of 130 pm EDT Sunday: Coastal cyclone is progged to translate north along the NC coast through tonight, with the accompanying loosening of the sfc pressure gradient and diminishing deeper moisture atop the western Carolinas. Scattered showers/patches of light rain along and east of I-77 will gradually ash out into early evening with residual piedmont/foothill low cloudiness within the ongoing NE flow hanging on into the night. With cloudiness struggling to developing west of the southern Blue Ridge, locally dense NC mtn valley fog is expected to develop by early Sunday morning. Expect continued weakening/backing of the mean flow atop the Southern Appalachians on Monday. Within the deep layered dry air, sunshine is on tap with afternoon maximums a few deg F above climo. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/... As of 1230 PM Sunday: Quiet weather is expected for the short term, as the coastal low slowly drifts east offshore and warm and dry high pressure builds into the region from the west. Skies should be clear to mostly clear thru the period, with some potential for mountain valley fog both nights. Temps will be about 5-10 degrees above normal. Lows mainly in the mid to upper 40s in the mountains and lower to mid 50s in the Piedmont. Highs in the mid 60s to mid 70s in the mountains and upper 70s to lower 80s in the Piedmont. && .LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/... As of 1245 PM Sunday: The upper pattern be very amplified at the start of the medium range, with deep trough over the Intermountain West, a ridge over the Mississippi Valley and a digging upper low over New England. The models are in good agreement that a dry backdoor cold front will slip thru the forecast area Wednesday. This will usher in slightly cooler temps for Thursday and Friday. Little to no cloud cover looks to continue, with temps close to normal. A slight rebound in temps is expected Saturday as the upper ridge axis begins to shift east to the East Coast. Low level flow will turn out of the SW and a front will approach from the west. The front may bring moisture back to the forecast area by Sunday, but the 12z deterministic guidance remains in disagreement on the timing and amount of moisture tap out of the Gulf. The latest National Blend of Models has 30-40% PoPs in the mountains and slight chc (15-25%) for most of the Piedmont on Sunday. Highs back into the upper 70s to near 80 in the Piedmont, and lows mainly in the 50s. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... At KCLT: Patches of light rain will continue floating by the terminal until near sunset as gusty NNE winds continue. Moist layer around 85H is progged to linger into tonight, so MVFR cigs will likely hang on until some point overnight thanks to a slowly thinning llvl moisture profile. Sunshine will eventually return on Monday along with a loosening sfc pressure gradient with the storm center pulling away from the NC coast. At the other TAF sites: Save for KHKY, which will remain under the gun for MVFR cig development, VFR conditions will continue into this evening as locally gusty NNE winds diminish. With nearly clear skies and light winds, the latest guidance continues to advertise locally dense mountain valley fog developing early Monday morning. Based on this, have trended the KAVL terminal to a more IFR fcst. Outlook: VFR conditions are expected to return region-wide on Monday and persist thru at least the middle of next week, although there will be some potential for mountain valley low stratus and/or fog each morning. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...None. NC...None. SC...None. && $$ SYNOPSIS...DEO NEAR TERM...CSH SHORT TERM...ARK LONG TERM...ARK AVIATION...CSH