012
FXUS62 KGSP 211136
AFDGSP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
736 AM EDT FRI AUG 21 2026
WHAT HAS CHANGED
THE AVIATION FORECAST WAS UPDATED FOR THE 12Z TAF ISSUANCE.
KEY MESSAGES
1. MORE WIDESPREAD COVERAGE OF SHOWERS AND THUNDERSTORMS IS
EXPECTED ACROSS THE AREA THIS AFTERNOON THROUGH THIS EVENING. A
FEW STORMS MAY BE SEVERE, PRODUCING DAMAGING WIND GUSTS. THERE
WILL ALSO BE A THREAT OF LOCALLY HEAVY RAINFALL AND ISOLATED
FLASH FLOODING.
2. DRIER WEATHER RETURNS SUNDAY AND CONTINUES INTO EARLY NEXT
WEEK. A RETURN OF AFTERNOON SHOWER AND THUNDERSTORM CHANCES IS
EXPECTED BY MIDWEEK.
DISCUSSION
KEY MESSAGE 1: MORE WIDESPREAD COVERAGE OF SHOWERS AND THUNDERSTORMS
IS EXPECTED ACROSS THE AREA THIS AFTERNOON THROUGH THIS EVENING. A
FEW STORMS MAY BE SEVERE, PRODUCING DAMAGING WIND GUSTS. THERE
WILL ALSO BE A THREAT OF LOCALLY HEAVY RAINFALL AND ISOLATED
FLASH FLOODING.
A DIGGING UPPER TROUGH COMBINED WITH HIGH PWATS WILL RESULT IN AN
ACTIVE CONVECTIVE DAY ACROSS THE AREA. AN MCS HAS OVERPERFORMED AS
IT CROSSES THE WESTERN HALF OF THE FORECAST AREA, BUT HAS BEEN ON A
GRADUAL WEAKENING TREND AS IT PUSHES INTO THE NC FOOTHILLS AND
PIEDMONT. THIS SYSTEM HAS ADDED SOME UNCERTAINTY ON HOW THE NEXT
ROUND OF CONVECTION WILL EVOLVE. THE DEBRIS CLOUDINESS AND LINGERING
SHOWERS AND STORMS HAVE WORKED OVER A GOOD CHUNK OF THE FORECAST
AREA THIS MORNING. ALREADY, THE LATEST HRRR AND 06Z NAMNEST ARE NOW
SHOWING CONVECTION FIRING ALONG THE EASTERN EDGE OF THE RESIDUAL
COLD POOL IN THE CHARLOTTE AREA EARLY THIS AFTN, BUT A NOTABLE LACK
OF ACTIVITY ACROSS THE REST OF THE AREA. THERE MAY STILL BE ENOUGH
TIME IN THE DAYLIGHT HEATING HOURS TO ALLOW ANOTHER ROUND OF
CONVECTION TO FORM ACROSS THE BLUE RIDGE AND TRACK EAST LATE
AFTN/EARLY EVENING.
THERE IS SOME SIGNAL FOR LOCALLY HEAVY RAINFALL, ESPECIALLY ACROSS
THE SOUTHEAST THIRD OR SO OF THE FORECAST AREA. PARTS OF THE
CHARLOTTE AREA DID RECEIVE SOME DECENT RAINFALL LAST NIGHT, SETTING
UP ELEVATED SOIL MOISTURE. A FLOOD WATCH WAS CONSIDERED, BUT
CONFIDENCE ON WHERE THE HEAVY RAIN SETS UP IS STILL TOO LOW. SOME
GUIDANCE KEEPS IT MOSTLY JUST EAST OF THE CWFA, WITH A SECONDARY
MAXIMUM ALONG THE EASTERN BLUE RIDGE ESCARPMENT. THE 00Z HREF HAS
SOME 3"+ PMM QPF BULLSEYES AROUND CHARLOTTE IN THE 21-00Z TIME
FRAME. THE REFS IS SIMILAR, BUT A LITTLE SOUTH AND EAST. SO THE
CONDITIONS BEAR WATCHING AND FLOOD WATCH MAY BE ISSUED LATER THIS
MORNING FOR PARTS OF THE CWFA, IF CONFIDENCE INCREASES.
THE OTHER CONCERN TODAY WILL BE A SEVERE THREAT. POCKETS OF 2000+
J/KG OF SBCAPE, ALONG WITH 25-30 KT OF 0-6 KM SHEAR COULD SUPPORT A
FEW SEVERE STORMS ORGANIZING ALONG OUTFLOWS AND PRODUCING DAMAGING
WIND GUSTS. VERY MOIST PROFILES SHOULD LIMIT DCAPE SOMEWHAT, AND
LIMIT COLD POOL FORMATION. NEVERTHELESS, THE NEW DAY 1 CONVECTIVE
OUTLOOK HAS CHARLOTTE AND VICINITY IN A SLIGHT RISK, AND MOST OF
THE REST OF THE CWFA IN A MARGINAL RISK FOR DAMAGING WIND GUSTS.
KEY MESSAGE 2: DRIER WEATHER RETURNS SUNDAY AND CONTINUES INTO EARLY
NEXT WEEK. A RETURN OF AFTERNOON SHOWER AND THUNDERSTORM CHANCES
IS EXPECTED BY MIDWEEK.
AN EASTERN CONUS UPPER TROUGH WILL CONTINUE TO DIG ON SATURDAY,
BUT THE AXIS WILL SHIFT SLIGHTLY EAST. THIS SHOULD ALLOW SOME DRIER
AIR TO FILTER IN FROM THE WEST, AS A SLOW-MOVING COLD FRONT WILL
STILL BE IN THE EASTERN PART OF THE CWFA. THERE WILL PROBABLY
BE ENOUGH LINGERING MOISTURE COMBINED WITH COOLER AIR ALOFT TO
ALLOW FOR SCATTERED DIURNAL CONVECTION TO DEVELOP AGAIN ACROSS THE
AREA. POPS WILL BE MAINLY IN THE LOW-END CHANCE RANGE, HIGHEST EAST.
THE UPPER TROUGH AXIS SHIFTS FURTHER EAST ON SUNDAY, AND USHERS IN
DRIER, MORE STABLE AIR COMPLETELY INTO THE REGION. DRY WEATHER WITH
SEASONABLY WARM CONDITIONS IS EXPECTED SUNDAY THROUGH TUESDAY. THEN,
THE TROUGH WILL LIFT NORTHEAST AND BRING BACK WARMER, MORE HUMID
CONDITIONS AND A RETURN TO DIURNAL CONVECTION BY THE MIDDLE OF
NEXT WEEK.
AVIATION /12Z FRIDAY THROUGH TUESDAY/
AT KCLT AND ELSEWHERE: A LINE OF THUNDERSTORMS HAS OVERPERFORMED
THIS MORNING, BUT IS FINALLY WEAKENING AS IT CROSSES THE KGMU/KGSP
SITES. CANNOT RULE OUT TS AT KHKY OR KCLT THIS MORNING, BUT
CHANCES ARE DOWN TO UNDER 30%, SO WILL GO WITH JUST VCSH FOR THAT
ACTIVITY. LATER TODAY, STILL EXPECT NUMEROUS TO WIDESPREAD SHRA AND
TSRA, ESPECIALLY AROUND KCLT. WITH THIS MORNING'S ACTIVITY WORKING
OVER THE UPSTATE AND NC MTNS, CONFIDENCE ACTUALLY DECREASED ON
TSRA AT THOSE SITES (WILL KEEP PROB30 FOR NOW). BUT THE TEMPO TSRA
AT KCLT STILL LOOKS GOOD. CONVECTION MAY LINGER INTO THE EVENING,
WITH HIGHEST CONFIDENCE OVER KCLT, SO WILL HAVE A PROB30 FOR MORE
TSRA THERE. WILL LEAVE OUT OF THE OTHER SITES FOR NOW. MVFR TO
IFR STRATUS MAY START DEVELOPING AFTER THE RAIN ENDS LATE THIS
EVENING ACROSS THE AREA, WITH MORE WIDESPREAD IFR CIGS AFTER 06Z
AND LINGERING INTO SATURDAY MORNING. WINDS WILL BE QUITE VRB THRU
THE PERIOD, ESPECIALLY AROUND THUNDERSTORMS, BUT SHOULD FAVOR A
NE DIRECTION THIS MORNING, THEN S/SE THIS AFTN.
OUTLOOK: ISOLATED TO SCATTERED AFTERNOON SHRA/TSRA MAY DEVELOP
AGAIN SATURDAY. BY SUNDAY, A DRIER PATTERN SHOULD ARRIVE AND LAST
THROUGH THE FIRST HALF OF NEXT WEEK, POSSIBLY KEEPING SHRA/TSRA
TO A MINIMUM THOSE DAYS. MOUNTAIN VALLEY FOG AND LOW STRATUS WILL
BE POSSIBLE EACH MORNING.
GSP WATCHES/WARNINGS/ADVISORIES
GA...NONE.
NC...NONE.
SC...NONE.
ARK
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