329
FXUS62 KGSP 261826
AFDGSP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
226 PM EDT FRI JUN 26 2026
WHAT HAS CHANGED
SHOWER AND THUNDERSTORM CHANCES HAVE INCREASED SLIGHTLY FOR THE
MOUNTAINS OVER THE WEEKEND.
KEY MESSAGES
1. AFTERNOON/EVENING SHOWER AND THUNDERSTORM CHANCES RETURN
THROUGH THE WEEKEND, WITH ISOLATED SEVERE STORMS POSSIBLE.
2. ELEVATED HEAT RISK BY MID-WEEK, WITH TRIPLE DIGIT HEAT INDICES
POSSIBLE ACROSS MOST LOCATIONS EAST OF THE MOUNTAINS.
DISCUSSION
KEY MESSAGE 1: AFTERNOON/EVENING SHOWER AND THUNDERSTORM CHANCES
RETURN THROUGH THE WEEKEND, WITH ISOLATED SEVERE STORMS POSSIBLE.
KICKING OFF THE WEEKEND WITH A MOSTLY ZONAL FLOW ALOFT AND A
SHORTWAVE PASSING THROUGH. MOISTURE ADVECTION FROM THE
SOUTH/SOUTHWEST, HELPS TO INCREASE SHOWER AND THUNDERSTORM ACTIVITY
CHANCES THROUGH THIS EVENING. GUIDANCE DOESN'T FAVOR MUCH IN THE WAY
OF ACTIVITY AS AN ENVIRONMENT WITH WEAK FLOW THROUGH THE MID-LEVELS
AND A WELL MIXED BOUNDARY LAYER, ISN'T CONDUCIVE FOR SEVERE
THUNDERSTORMS. HOWEVER, MODELED SOUNDINGS SHOW A STOUT INVERTED-V
WITH 800-1000 J/KG OF DCAPE, INDICATING THAT ANY STORM THAT DOES
EMERGE, COULD PRODUCE STRONG WINDS. A FEW POP-UP SHOWERS OR
THUNDERSTORMS OVER THE MOUNTAINS AND ISOLATED LOCATIONS EAST OF THE
MOUNTAINS ARE POSSIBLE THROUGH THE EVENING.
FOR THE WEEKEND, A SIMILAR PATTERN EMERGES, BUT WITH ONE CAVEAT. A
DEVELOPING RIDGE ACROSS THE CENTRAL CONUS BEGINS TO BUILD, LEAVING
THE SOUTHEAST AND PORTIONS OF THE MID-ATLANTIC IN THE PATH OF
POTENTIAL DOWNSTREAM CONVECTION. DEPENDING ON HOW QUICKLY THIS RIDGE
DEVELOPS AND WHERE THE AXIS SETS UP, WILL HAVE A DIRECT IMPACT ON
WHAT, IF ANY, SEVERE THUNDERSTORMS COULD OCCUR. CURRENT GUIDANCE HAS
A SERIES OF SHORTWAVES MOVING THROUGH THE CAROLINAS THROUGH SUNDAY,
ENHANCING THE CHANCES FOR SHOWERS AND THUNDERSTORMS. THE MOUNTAINS
HAVE THE HIGHEST CHANCES (50-70%), WITH ONLY A SLIGHT CHANCE
ELSEWHERE. EITHER WAY, IT'S SUMMERTIME. EXPECT A FEW STORMS TO POP
UP, ESPECIALLY NEAR THE MOUNTAINS.
KEY MESSAGE 2: ELEVATED HEAT RISK BY MID-WEEK, WITH TRIPLE DIGIT HEAT
INDICES POSSIBLE ACROSS MOST LOCATIONS EAST OF THE MOUNTAINS.
AS THE RIDGE OUT WEST CONTINUES TO AMPLIFY AND MOVE EASTWARD, THE
PROBABILITY OF TRIPLE DIGIT HEAT INDICES INCREASES. THIS STOUT AREA
OF HIGH PRESSURE BUILDS IN HOT SUMMER HEAT THROUGH THE WEEKEND AND
CONTINUES TO RISE INTO NEXT WEEK. AT THIS TIME, GUIDANCE HAS A 70-
80% PROBABILITY OF TEMPERATURES EAST OF THE MOUNTAINS REACHING 95
DEGREES OR HIGHER FROM WEDNESDAY ONWARD. GIVEN THE INCREASE IN
MOISTURE RESULTING IN ELEVATED DEWPOINTS, THIS RAISES CONCERNS FOR
MULTIPLE DAYS OF HEAT INDICES OF 100+. THE ONE CAVEAT, ESPECIALLY
FOR THE WEEKEND, IS ANY LOCATION THAT HAS A SHOWER OR THUNDERSTORM
COULD COOL ISOLATED AREAS. BUT, REGARDLESS, THE SIGNALS ARE THERE IN
THE GUIDANCE FOR A MULTI-DAY HEAT EVENT, LEADING UP TO THE 4TH OF
JULY WEEKEND. FOR THIS, IT'S IMPORTANT TO PLAN FOR STAYING COOL.
THOSE WHO ARE OUTDOORS SHOULD HYDRATE FREQUENTLY AND TAKE BREAKS IF
WORKING OUTSIDE.
AVIATION /18Z FRIDAY THROUGH WEDNESDAY/
AT KCLT AND ELSEWHERE: VFR CONDITIONS PREVAIL THROUGH THE TAF
PERIOD. A FEW SCATTERED SHOWERS AND TSRA FROM NOW THROUGH 00Z. KAVL
IS MORE LIKELY TO HAVE A TSRA BUT CONFIDENCE STILL REMAINS LOW, SO A
PROB30 REMAINS. GIVEN THE RA THROUGH KCLT EARLIER, A PROB30 SHOULD
SUFFICE FOR NOW AS CONFIDENCE IS ALSO LOW. THERE COULD BE A BRIEF
PERIOD THROUGH 23Z OF LOW-END GUSTS OF 15-20KTS AT KCLT AS WELL.
OTHERWISE, VCTS ELSEWHERE AND 5-10KT WINDS OUT OF THE SW. OVERNIGHT,
A FEW TERMINALS MAY BECOME VRB BEFORE PICKING BACK UP FROM THE SW
SATURDAY MORNING.
OUTLOOK: AFTERNOON/EVENING SHOWER AND THUNDERSTORM CHANCES AND
ASSOCIATED RESTRICTIONS CONTINUE THROUGH THE WEEKEND. EARLY MORNING
FOG/LOW STRATUS IS POSSIBLE EACH DAY, ESPECIALLY IN THE MOUNTAIN
VALLEYS.
GSP WATCHES/WARNINGS/ADVISORIES
GA...NONE.
NC...NONE.
SC...NONE.
CP
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