012 FXUS62 KGSP 100144 AFDGSP Area Forecast Discussion National Weather Service Greenville-Spartanburg SC 944 PM EDT Mon Jun 9 2025 .SYNOPSIS... Scattered showers and thunderstorms crosses our area from Georgia tonight then moves out of our area early Tuesday. Weak and mostly dry high pressure controls our weather Tuesday and Wednesday. A Bermuda high creates a moist southerly flow late this week and into next week with scattered to numerous showers and storms affecting our region. && .NEAR TERM /THROUGH TUESDAY/... As of 934 PM Monday: Convection has congealed along the I-77 corridor, but is significantly less impressive than it was even an hour ago, as the atmosphere is now mostly worked-over, and further destabilization isn`t expected. A tight band of showers over the I-26 corridor should lose steam crossing the Upstate, giving way to quieter conditions overnight. Meanwhile, a weak cold front associated with low pressure lifting northeastward from the Great Lakes to Ontario will get pushed over the mtns and will probably stall thru morning. Low temps will be seasonally mild. Tuesday is a bit uncertain as along as a boundary remains laid out SW-to-NE across the mtns, which the GFS shows. If the boundary remains in place, the Marginal Risk on the Day 2 Outlook looks like a good call. The 15Z RAP develops an environment with muCAPE around 2500 J/kg to the S and E of I-85 in the afternoon with maybe 25 kt of effective bulk shear, which is enough to get a few strong to severe storm clusters in that area. The CAMs depict a similar idea. Keep that idea simmering on a back burner. Over the mtns and foothills, high pressure would be building in behind the front, so storm chances would be much less. The boundary and increased clouds will keep temps down a few degrees below today. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... As of 1245 PM EDT Monday: Upper trough in place over the Appalachians with exiting front at the start of the short term will leave dry conditions in place for Wednesday, but with downsloping and subsidence in the NW flow aloft, temperatures will bump up a couple of degrees from Tuesday but still rather seasonal as the front remains well to the south. Meanwhile, a cutoff midlevel low will be meandering around the Southern Plains, and as it lifts toward the MO Valley on Thursday, the front will be pulled back north with it. Southerly return flow around the western periphery of the Bermuda high will contribute to the increasingly moist airmass, with temperatures rising slightly higher still on Thursday and a return of afternoon convection. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... As of 115 PM EDT Monday: Upper ridge over the surface Bermuda high will slowly retrograde west toward the Southeast coast as we approach the weekend, but operational guidance handles the Plains mid-level cutoff differently. Ensemble guidance all points to above- normal temperatures and increased upper support for enhanced diurnal coverage more than typical summertime convection, especially in the mountains closer to the shortwaves that will be lifting over the ridge. However, no real deep-layer shear to speak of and poor lapse rates due to the mid-level ridging may preclude much in the way of severe convection despite additional coverage. Will have to evaluate daily threats for isolated wet microbursts as well as building hydro potential late in the period. && .AVIATION /02Z TUESDAY THROUGH SATURDAY/... At KCLT and elsewhere: A cluster of strong to severe convection is underway across the SC Upstate zones this evening, with less-pronounced activity across the NC mountains nonetheless producing flight restrictions at KAVL. The cluster is expected to pivot northeastward over the next 1-2 hours, with short TEMPOs in place for the Upstate terminals, and only KCLT expecting TS/SHRA to continue past 02z. Once the activity shifts east...expect gradually descending ceilings overnight, with MVFR to IFR cigs forecast along and south of I-85 through daybreak. Farther north, generally drier surface conditions are indicative of a better trend overnight...with at worst, MVFR cigs expected for KAVL and KHKY leading up to dawn. Guidance isn`t super-consistent with this feature, but especially given the intense rainfall currently being received in parts of the Upstate, confidence is high enough to include solid IFR at CLT, GSP, GMU, and AND. VFR conditions will return on Tuesday as ceilings scatter out. An afternoon cu field should develop again, but with abnormally low bases in the 030-040 range as moist SW flow continues and sfc dewpoint depressions remain small. A raggedy line of convection is depicted in most guidance exiting the NC mountains and sliding SE across the terminal forecast area through Tuesday afternoon...but coverage appears low enough that a PROB30 for TSRA has only been included at CLT for the time being. Outlook: Mostly VFR Wednesday. Mainly diurnal thunderstorms return Thursday and will persist each afternoon/evening into the weekend. There will be potential for late night and early morning fog and low stratus restrictions each day. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...None. NC...None. SC...None. && $$ SYNOPSIS...DEO NEAR TERM...MPR/PM SHORT TERM...TDP LONG TERM...TDP AVIATION...MPR