Area Forecast Discussion
Issued by NWS Greer, SC

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000 FXUS62 KGSP 061955 AFDGSP Area Forecast Discussion National Weather Service Greenville-Spartanburg SC 255 PM EST Sat Mar 6 2021 .SYNOPSIS... Canadian high pressure will continue to build across the forecast area this afternoon into tonight as a low pressure system located in the eastern Gulf of Mexico tracks to the southeast. Dry high pressure will gradually track east towards the East Coast tomorrow into much of next week leading to continued dry weather and warmer temps. Friday into Saturday a cold front will approach from the west leading to the potential for increased rain chances. && .NEAR TERM /THROUGH SUNDAY/... As of 230 PM EST Saturday: Low clouds and sprinkles are moving southeast out of the area as the short wave responsible for the forcing moves southeast as well. Expect mostly sunny skies and mild temps for the rest of the afternoon. The upper trough strengthens over the area tonight as a channeled short wave drops into the area. May see an increase in mountain wave cirrus this evening as some upper level moisture moves overhead. Some shallow low level moisture moves into the mountains toward daybreak. This may cause an increase in clouds across the mountains, and possibly some flurries at the highest elevations. However, no significant precip expected given the weak forcing and shallow nature of the moisture. Breezy winds will continue across the mountains as well. Lows will be 5 to 10 degrees below normal. Heights begin to slowly rise Sunday as the channeled short wave moves east. Expect some rebound in temps and across NE GA and the Upstate while temps across NC remain nearly steady. Expect breezy to windy conditions to develop as deep mixing taps some higher winds moving in with the short wave. This mixing will also tap drier air leading to very low RH values. See fire weather discussion for details. && .SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/... As of 200 PM Saturday: The back end of the upper trough will continue to push offshore during the beginning portions of the short term. Higher heights will increase during the early part of next week as an upper ridge builds in from the west. Broad Canadian high will control the overall weather during the period as it sets up shop over the Carolinas and very gradually pushes just off the Carolina coastline by Tuesday. A slight wind shift will be in store as a light return flow from the S/SW works into the region by Tuesday as the sfc high moves offshore. One forecast concern will be the RH values across the region as dewpoints remain in the 10s and 20s for a good chunk of the short term. This will prog fire weather concerns, which will be provided in greater detail in the Fire Weather discussion. Min T`s will remain below-normal Sunday night, but rebound to near-normal Monday night. A similar trend occurs with Max T`s as near-normal values will be likely on Monday, while jumping ~5+ degrees on Tuesday. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... As of 250 pm Saturday: Dry weather will continue with heights building over the Eastern US Tuesday night into Wednesday due to the subtropical ridge strengthening in the Gulf of Mexico. Thursday into Friday high pressure will start to slide off into the western Atlantic; however, the southwestern periphery of the ridge will continue to extend into the Carolinas and NE Georgia. This pattern will lead to above normal high temps early next week becoming well above normal middle to late week. Friday into Saturday a cold front could bring rain chances back into the forecast. Model guidance is not in agreement in regards to the arrival of the cold front and its associated moisture. Currently the ECMWF and Canadian have the front pushing into the area Friday while the GFS has the front well to our west for most of the weekend. Due to low confidence on the timing of this front, we have kept a slight chance for rain across far western NC for Friday. Saturday we introduced a slight chance of rain for much of the forecast area. We will continue to monitor the progression of this pattern in the coming days. && .AVIATION /20Z SATURDAY THROUGH THURSDAY/... At KCLT and elsewhere: VFR through the period at the TAF sites. Low clouds moving south and east of the area as a short wave moves out of the area. Expect clear skies across the area by sundown. Winds will remain N to NW for the NC sites this afternoon, with low end gusts at KAVL, and SW for the SC sites. Winds turn back to N to NE overnight then pick back up from the N to NW, with stronger gusts at KAVL, on Sunday. Can`t rule out some low VFR clouds across the mountains late tonight into early Sunday, but should remain NE of KAVL. Outlook: Dry high pressure will remain in control well into next week with VFR conditions prevailing. Confidence Table... 00-06Z 06-12Z 12-18Z 18-00Z KCLT High 100% High 100% High 100% High 100% KGSP High 100% High 100% High 100% High 100% KAVL High 100% High 100% High 100% High 100% KHKY High 100% High 100% High 100% High 100% KGMU High 100% High 100% High 100% High 100% KAND High 100% High 100% High 100% High 100% The percentage reflects the number of guidance members agreeing with the scheduled TAF issuance flight rule category. Complete hourly experimental aviation forecast consistency tables are available at the following link: && .FIRE WEATHER... A very dry day expected Sunday as deep mixing and a dry air mass lead to minimum RH values in the 15-25% range across the entire forecast area during the afternoon. Elevated mountain winds, generally 15-20 mph with higher gusts are expected as well. After coordination with the USFS in Asheville, will issue a Fire Danger Statement for the NC mountains. NE GA will likely need one as well. However, after coordination with FFC, will hold off on issuance until the morning to avoid confusion, as they are uncertain how much of central and southern GA will be covered. Coordination may be needed with NCFS for the foothills and Piedmont where winds won`t be as strong but RH will be very low. Monday will be warmer with even drier RH values. Winds won`t be as strong, so statements not as likely over NC, but NE GA will likely need another statement. Moisture recovers some Tuesday, but low RH will again be possible with NE GA likely the main location for fire danger with winds relatively light once again. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...None. NC...Fire Danger Statement from Sunday afternoon through Sunday evening for NCZ033-048>053-058-059-062>065. SC...None. && $$ SYNOPSIS...AP NEAR TERM...RWH SHORT TERM...CAC LONG TERM...CAC AVIATION...RWH FIRE WEATHER...RWH is the U.S. government's official web portal to all federal, state and local government web resources and services.