304
FXUS62 KCAE 282354
AFDCAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
754 PM EDT FRI AUG 28 2026
WHAT HAS CHANGED
THUNDERSTORMS CONTINUE TO PUSH INTO THE NORTHERN MIDLANDS AND
PEE DEE THIS EVENING.
KEY MESSAGES
- 1. DIURNAL THUNDERSTORMS EXPECTED THROUGH THE WEEKEND WITH THE
MAIN THREAT OF LOCALLY HEAVY RAINFALL.
- 2. DANGEROUS HEAT INDEX VALUES POSSIBLE NEXT WEEK.
DISCUSSION
KEY MESSAGE 1: DIURNAL THUNDERSTORMS EXPECTED THROUGH THE
WEEKEND WITH THE MAIN THREAT OF LOCALLY HEAVY RAINFALL.
THUNDERSTORMS WILL PUSH INTO THE FORECAST AREA FROM THE NORTH
THIS EVENING AS OUTFLOW FROM NC SLOWLY SINKS SOUTH. ANOTHER
OUTFLOW FROM CONVECTION TO OUR SOUTH IS PUSHING NORTH. THESE
FEATURES WILL BE THE MAIN FOCUS FOR CONVECTION IN THE NEAR TERM.
A BOUNDARY COLLISION OVER THE CENTRAL MIDLANDS COULD SPARK
ADDITIONAL THUNDERSTORMS TONIGHT. THE EXTENSIVE CLOUD COVER
THIS MORNING LARGELY INHIBITED INSTABILITY ACROSS THE AREA,
LOWERING CHANCES FOR SEVERE WEATHER. BUT SLOW MOVING STORMS AND
MOISTURE-RICH PROFILES WILL FAVOR HEAVY, EFFICIENT RAINFALL.
THE BIGGEST THREAT WILL BE HEAVY RAIN AS STORMS LINGER INTO THE
EVENING AND OVERNIGHT.
MORE OF THE SAME IS EXPECTED ON SATURDAY AND SUNDAY. CLOUD
COVERAGE WILL LIKELY HANG AROUND IN THE MORNING HOURS, AND ITS
EXTENT AND DURATION IS EXPECTED TO MODULATE STORM CHANCES &
TIMING EACH AFTERNOON. WITH PWS >2" BOTH DAYS, EXPECT SHOWERS
AND STORMS TO CONSISTENTLY BE A THREAT. THE BETTER FORCING DOES
LOOK TO BE IN PLACE ON SATURDAY AS THE TROUGH WILL STILL BE IN
PLACE TO OUR WEST (DESPITE IT GRADUALLY WEAKENING AND LIFTING
NORTHWARD). ISOLATED INSTANCE OF FLASH FLOODING WILL REMAIN A
THREAT BOTH DAYS, WITH HIGHS IN THE MID TO UPPER 80S.
KEY MESSAGE 2: DANGEROUS HEAT INDEX VALUES POSSIBLE NEXT WEEK.
AS WE GET INTO NEXT WEEK (AND REALLY INTO THE BEGINNING OF
SEPTEMBER), THERE REMAINS A STRONG SIGNAL FOR ABOVE NORMAL
TEMPERATURES. AN ANOMALOUS 500 HPA RIDGE IS FORECAST TO BUILD
ACROSS THE CENTRAL PLAINS ON SUNDAY AND BEGIN TO FLEX ITS
STRENGTH EASTWARD ACROSS THE SOUTHEASTERN CONUS BY THE MIDDLE OF
NEXT WEEK. ENSEMBLES ARE ALREADY PAINTING A STRONG SIGNAL FOR AN
ANOMALOUS AND EXTENDED HEAT WAVE. ECE EFI VALUES FOR TEMPERATURE OF
0.7-0.8 & NON-ZERO SHIFT OF TAILS VALUES IN THE 4-8 AND 5-9 DAY
PERIODS SUGGEST THE POTENTIAL FOR ANOMALOUS TEMPS ACROSS THE
AREA FOR AN EXTENDED PERIOD FROM TUESDAY OF NEXT WEEK THROUGH
THE END OF THIS FORECAST PERIOD. SOME GUIDANCE DISAGREES ON
WHERE THE RIDGE SETTLES BY THE END OF NEXT WEEK BUT CONFIDENCE
IS INCREASING IN ANOMALOUS TEMPS IN THE MID/UPPER 90S IN THE
TUES- FRI PERIOD OF NEXT WEEK. SURFACE DEWPOINTS LOOK HIGH AS
WELL, INCREASING THE PROBABILITY THAT WE SEE HEAT INDEX VALUES
OF AT LEAST 100F-105F MULTIPLE DAYS IN A ROW NEXT WEEK, WITH
LIMITED SHOWER/STORM CHANCES TO HELP AID IN THE HEAT.
AVIATION /00Z SATURDAY THROUGH WEDNESDAY/
GUIDANCE HAS REMAINED CONSISTENT SHOWING LOW STRATUS AND FOG
DEVELOPMENT AGAIN SATURDAY MORNING. THIS IS IN LINE WITH THE
PAST FEW MORNINGS. HOWEVER WITH THUNDERSTORMS LOOKING LESS
LIKELY THIS EVENING AT THE TAF SITES, THIS COULD BE A DIFFERENCE
BETWEEN TONIGHT AND PREVIOUS NIGHTS. EVEN IF FOG DOES NOT
DEVELOP, WE WOULD EXPECT IFR OR LIFR CEILINGS AT ALL TERMINALS
FROM ABOUT 09-14Z. HAVE ALSO INTRODUCED SHOWERS AT KOGB AFTER
14Z AS GUIDANCE SUGGESTS CONVECTION REDEVELOPING ALONG THE
COASTAL PLAIN SATURDAY MORNING AS WEAK LOW PRESSURE DEVELOPS
OFFSHORE. CEILINGS MAY NOT RISE TO VFR LEVELS AT MOST TERMINALS
UNTIL LATE SATURDAY. ONCE AGAIN, SCATTERED THUNDERSTORMS ARE
EXPECTED IN THE AFTERNOON SO WE HAVE INTRODUCED A TEMPO GROUP TO
ACCOUNT FOR THE SCATTERED NATURE OF THE STORMS AND OVERALL
UNCERTAINTY IN IMPACTS TO THE TERMINALS.
EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE FROM SHOWERS
AND THUNDERSTORMS INTO THIS WEEKEND. DRIER CONDITIONS EXPECTED
EARLY NEXT WEEK.
CAE WATCHES/WARNINGS/ADVISORIES
SC...NONE.
GA...NONE.
DISCUSSION...PL
AVIATION...CJR
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