Area Forecast Discussion
Issued by NWS Greer, SC
Issued by NWS Greer, SC
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487 FXUS62 KGSP 191735 AFDGSP Area Forecast Discussion National Weather Service Greenville-Spartanburg SC 135 PM EDT Thu Sep 19 2024 .SYNOPSIS... The limited coverage of any showers and storms on Friday afternoon will be confined to the mountains. Meanwhile, high pressure begins to build into the region from the north and west giving our region a dry weekend. Temperatures will be above normal through the weekend then closer to normal through the middle of next week. && .NEAR TERM /THROUGH TONIGHT/... 1000 AM Update...The forecast is in good shape at this hour. Current Vis Sat loop is showing a breakup in the StCu deck across the Piedmont and expect this trend to continue thru the early afternoon. Still anticipate temps to recover quickly in this area with highs reaching the l80s, while areas to the southwest reach the u80s. Afternoon showers and a few general thunderstorms producing locally high rainfall rates will be confined mainly to the NC mtns and will likely begin development arnd 18z. The going HWO looks properly placed and no changes were needed to the product. Tonight...Convection may linger into the evening, as activity drifts south out of VA and extreme NW NC. But this activity should be on a weakening trend and not expected to be organized. With less mid and high clouds expected than last couple nights, may see a better radiation fog night with possibly some low stratus developing as well. Lows will be a category or so above normal. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... As of 145 AM EDT Thursday: The CFWA will be situated between the departing shortwave trough lifting into the northeastern CONUS and an upper anticyclone over northern Mexico and the Southern Plains at the beginning portion of the forecast period. As a result, expect for increasing subsidence over the area as higher heights filter into the CFWA through much of the period as upper ridging slowly propagates eastward and essentially shuts down rain chances for most locations. Surface high will sliver down the Appalachians from the Atlantic Canada/Hudson Bay area and keep dry conditions in place, outside of a slight chance PoP over the Blue Ridge Escarpment on Friday. Drier airmass will be in place, but model guidance have a hard time sending a backdoor front this far south in response to the area of high pressure nosing into the region. In this case, dewpoints will remain in the 60s, with increasing temperatures and thus, a drier but still humid airmass will remain in place. Not much change in the sensible weather for Saturday, but the upper ridge axis will continue to make a run at the southeastern CONUS from the west, so afternoon highs for Friday will be a few ticks above normal, while Saturday`s afternoon highs uptick to a category or two above normal. Overnight lows will run a few ticks above normal for both Friday and Saturday night thanks to elevated dewpoints despite better radiational cooling conditions. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... As of 320 AM EDT Thursday: Upper ridge axis will continue to track across the southeastern CONUS and pass through the CFWA by early next week. As a result, temperatures will remain elevated as warm air aloft promotes our warmest day to be Sunday with afternoon highs almost two categories above normal, while afternoon highs Monday and Tuesday are forecasted to be at or slightly above normal. A shortwave trough will be in the midst of swinging across the Midwest with an attendant cold front encroaching the CFWA from the west as the upper ridge axis slips east of the area. Overall timing and placement of said cold front is still uncertain amongst model guidance, but the synoptic setup is relatively in-check. A gradual uptick in PoPs will be presented in this scenario as the frontal boundary inches closer to the region, with an emphasis on increasing PoPs across the mountains during the medium range. Temperatures are forecasted to return back to normal or even a few ticks below normal by D6/D7 with more cloud cover and mentionable PoPs returning back into the forecast. && .AVIATION /18Z THURSDAY THROUGH TUESDAY/... At KCLT and elsewhere: VFR conds will continue across all sites this evening, except at KCLT where BKN MVFR may persist off and on over the next couple hours. Scattered showers and a couple thunderstorms will develop across the mtns, but confidence is too low for a precip/vsby mention at KAVL and KHKY. Good rad cooling overnight will help develop fog, possibly VLIFR, at KAVL and KHKY, while MVFR restrictions due to VSBY and CIGs is possible at KCLT arnd and thru daybreak. VFR conds return all sites aft 14z and continue thru the period. Winds remain aligned generally ne/ly and low-end. Outlook: No appreciable return of moisture or precip chances expected until early to middle of next week. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...None. NC...None. SC...None. && $$ SYNOPSIS...CAC NEAR TERM...ARK/SBK SHORT TERM...CAC LONG TERM...CAC AVIATION...SBK