Area Forecast Discussion
Issued by NWS Greer, SC
Issued by NWS Greer, SC
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364 FXUS62 KGSP 271833 AFDGSP Area Forecast Discussion National Weather Service Greenville-Spartanburg SC 233 PM EDT Mon May 27 2024 .SYNOPSIS... Cooler and drier conditions return Tuesday through Saturday. By the end of next weekend, high pressure will become centered near Bermuda which creates a southerly flow with more humidity. && .NEAR TERM /THROUGH TUESDAY/... As of 215 PM EDT Monday: Deep stacked low over the Great Lakes region has placed the CFWA into a warm sector regime as a cold front encroaches the region from the northwest. Airmass recovery is underway as cloud debris from the showers and thunderstorms this morning scour out. Lots of sunshine out there right now, but not necessarily a good thing. With good kinematics in place, destabilization is the one lacking parameter that`s holding the CFWA back from receiving decent severe weather coverage. Current mesoanalysis indicates that the atmosphere should recover and develop 1000-2000+ J/kg of sbCAPE to go along with 30-40 kts of effective bulk shear and 1000+ J/kg of DCAPE by late this afternoon. CAMs are not excited about convection firing up this afternoon/evening, ahead of the cold front. Strong to severe storms will be possible with any that develop, with the main threats being large hail and damaging winds. An isolated tornado can`t be ruled, but SRH are not impressive, while low-level shear is high enough to complete tornadogenesis. Storm mode would support supercells and multi-clusters if a few cells form in the same area, mainly across western NC and northern Upstate SC. Afternoon highs will be near normal due to cloud debris from earlier. The aforementioned cold front will enter the CFWA from the west later this evening and complete a full fropa just before daybreak Tuesday. Winds will turn to a west-northwesterly to northwesterly component, dry air entrainment prevails through the rest of the period. A few showers may develop behind the front along the NC/TN border after the front passes just before midnight tonight, but that`s about all that will be squeezed out of what`s left in the shallow layer of low- level moisture. Broad upper troughiness will set up shop over the eastern CONUS through the end of the near-term as heights drop a few dm. Post-frontal conditions will be in store for Tuesday as a downslope component filters in and dewpoints lower into the 50s, with highs still managing to reach the low to mid 80s for most locations outside of the higher elevations. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... As of 1255 PM Monday...The short range period begins with nearly zonal flow aloft as a cP sfc high builds south out of Canada. This airmass will mix into the fcst area thru the period and help maintain low RH values during the afternoon and the overnight periods. Thus, a dense fog threat will be quite limited. With near normal temps each afternoon, conds will be rather pleasant due to the prevailing dry air. The latest GFS continues to show a weak bndry ahead of the sfc high bringing limited amts of llvl moisture to the wrn NC mtns Wed evening, but confidence is too low for a PoP mention as other guidance mixes in a good amt of dry air within the bndry convg zone. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... As of 115 PM Sunday...Upper heights fall quickly early in the ext range as a strong ulvl trof swings south over the ern CONUS. This trof will provide upward vertical forcing, however, precip generation will be quite limited due to a broad Canadian high shunting GOM and Atl moisture transport into the FA. The column remains deeply dry Fri and Sat, with the best chance for precip possibly not returning until Sun as a srn stream h5 s/w advances toward the area. Even this low precip potential is uncertain as the ECMWF is the only op model showing any QPF response as the other models keep a GOM moisture feed closed. Temps will cool a little in this environment as the cP airmass builds in more fully. Highs will likely be held a couple degrees below normal Fri thru the weekend, while lows remain near normal. && .AVIATION /19Z MONDAY THROUGH SATURDAY/... At KCLT and elsewhere: Southwesterly winds with low-end gusts will remain in place through the evening, ahead of an encroaching cold front. Cloud debris from the showers and thunderstorms earlier today has mostly scoured out. Lingering cu (040-050) will continue to roam the sky, with some potentially expanding into a shower or thunderstorm. Confidence was only high enough at KCLT for a TEMPO thunderstorm and associated restrictions. Kept the rest of the TAFs in the 18Z update dry. A shower or thunderstorm can`t be ruled out elsewhere, but confidence was too low for a mention at this time due to isolated coverage in the forecast. The cold front will sweep across the area overnight as winds turn to a west-northwesterly component and remain that way through the rest of the forecast period. Some high clouds and diurnally driven cu may develop Tuesday afternoon, while conditions remain dry and VFR at all terminals. Some low-end gusts are expected during peak heating Tuesday as well. Outlook: Drier weather is expected Tuesday thru the end of the week with VFR conditions. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...None. NC...None. SC...None. && $$ SYNOPSIS...DEO NEAR TERM...CAC SHORT TERM...SBK LONG TERM...SBK AVIATION...CAC