Area Forecast Discussion
Issued by NWS Greer, SC

Current Version |  Previous Version |  Text Only |  Print | Product List |  Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
408 FXUS62 KGSP 292320 AFDGSP Area Forecast Discussion National Weather Service Greenville-Spartanburg SC 720 PM EDT Wed May 29 2024 .SYNOPSIS... A cooler and drier air mass will gradually build into the region through the end of the week, with high pressure moving across the region at the start of the weekend. Once the high moves off to our east on Sunday, we should see a slow warm up with a return of the mainly afternoon and evening showers and thunderstorms. && .NEAR TERM /THROUGH THURSDAY/... As of 600 PM EDT Wednesday: No major changes were needed this update as the forecast remains on track. Still seeing dry conditions across the CWA with few to scattered diurnal cumulus. Upper cirrus is creeping in from the west and southwest and should gradually thicken through the next several hours. Otherwise, omega block is in full force across the eastern CONUS. Water vapor imagery shows a trough over the upper OH Valley and Northeast, with nearly cutoff embedded shortwave spinning near Pittsburgh. Via this pattern, some degree of DPVA will occur over our area this evening although the shortwave will pass by to our north. Similar to yesterday, a relatively shallow convective layer will be present beneath this feature but still capped by subsidence inversion. Some congested or towering cumulus thus may be seen across the CWA thru evening, perhaps resulting in brief, isolated sprinkles, but chance of measurable rainfall still looks to be near zero. Deep mixing will result in low-end wind gusts through this evening, especially across the mtns. A dry, reinforcing cold front will push across the area overnight behind the departing shortwave, promoting a further decline in dewpoints. Despite temps also trending a few degrees below normal, the drying should make for a fog-free night once again, except for the Little TN Valley, where patchy fog may develop. Temps likewise end up a little below normal for Thursday. Another embedded shortwave will rotate through the trough late Thursday but without enough moisture to justify mentionable PoPs. Mixing won`t be as deep, leading to lighter winds on Thursday. Cumulus will develop once again Thursday afternoon and early evening. && .SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/... As of 1205 PM EDT Wednesday: No changes to the going forecast to round out the month of May as we remain under dry Northerly flow aloft on Friday. In the wake of vort energy rippling toward the base of eastern seaboard trough axis, full sunshine is expected with Piedmont maximums around 80 along with surface dwpts well below climo. Progressive upper ridge axis builds into and translates across the region on Saturday and the llvl flow will come around to south. This will aid in boosting maximums a couple of deg F above Friday`s readings. The atmosphere will also become weakly unstable Saturday afternoon, and coincident with weak Ohio Valley s/wv energy skirting by, there could be a few showers developing in the NC mountains. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
-- Changed Discussion --
As of 130 PM EDT Wednesday: Diurnally enhanced summer-like thunderstorm chances return to the forecast for the latter half of the upcoming weekend as a quasi-zonal wavy pattern develops atop the SE CONUS. In fact, there is little discernible change expected for the daily sensible weather through the early part of next week as triggering mechanisms for daily thunderstorm chances will be driven by a mix of synoptic scale s/wv and mesoscale features, along with the typical terrain aided forcing here in the southern Appalachians. Temperatures will be warming through the period, maximums rising to the early June climo on Monday, but into the upper 80s by Wednesday. Along with a daily increase in sfc dwpts will promote summertime heat and humidity by the middle of next week as well.
-- End Changed Discussion --
&& .AVIATION /00Z THURSDAY THROUGH MONDAY/...
-- Changed Discussion --
At KCLT and elsewhere: VFR through the 00Z TAF forecast period thanks to dry sfc high pressure building into the region behind a dry cold front tracking across the western Carolinas this evening into tonight. A few VFR cumulus are lingering across the terminals this evening but these should dissipate shortly after sunset. SCT to BKN VFR cirrus has been streaming ENE into the region out of the WSW. This cirrus should mainly impact the SC Upstate terminals and KCLT over the next few hours. Winds are mainly NW/WNW this evening but should turn more N after midnight east of the mtns. Wind gusts should gradually taper off through the early evening hours. Winds at KAVL should remain WNW through the 00Z TAF period. No fog is expected to develop overnight at any of the terminals thanks to drier air filtering in behind the cold front. Winds Wednesday morning and early afternoon will toggle more NE east of the mtns and may toggle back NW towards the end of the TAF period. However, confidence on this is very low so maintained NE winds through the rest of the TAF forecast period east of the mtns. Winds will be lighter compared to the last two days, with no wind gusts expected on Wednesday. Afternoon cumulus should return but will remain VFR. Outlook: VFR conditions will persist ,along with with dry weather, through the end of the workweek. Shower and thunderstorm chances may return this weekend.
-- End Changed Discussion --
&& .GSP WATCHES/WARNINGS/ADVISORIES... GA...None. NC...None. SC...None. && $$ SYNOPSIS...DEO NEAR TERM...AR/Wimberley SHORT TERM...CSH LONG TERM...CSH AVIATION...AR