750
FXUS62 KCHS 301327
AFDCHS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
927 AM EDT WED JUL 30 2025
SYNOPSIS
ATLANTIC HIGH PRESSURE WILL PREVAIL EAST OF THE AREA FOR MOST
OF THE WEEK, ALONG WITH A TROUGH OF LOW PRESSURE INLAND. A COLD
FRONT MAY STALL NEAR THE AREA THIS WEEKEND.
NEAR TERM /THROUGH TONIGHT/
MID AND HIGH-LEVEL DEBRIS CLOUDINESS GENERATED BY CONVECTION
THAT SPARKED OVER THE CHARLESTON TRI-COUNTY INTO COLLETON COUNTY
EARLIER THIS MORNING HAS SLOWED TEMPERATURES RISES MORE THAN
EXPECTED ACROSS NORTHERN AREAS THIS MORNING. GOES-E VISIBLE DATA
DO SHOW SOME BREAKS ARE STARTING TO OCCUR IN THAT AREA WITH
SUNNY SPELLS BEING OBSERVED AT TIMES. NEAR TERM GUIDANCE STILL
SUGGESTS HIGHS SHOULD TOP OUT IN THE LOWER 90S ACROSS THE TRI-
COUNTY AND THE REMAINDER OF SOUTHERN SOUTH CAROLINA WITH MID-
UPPER 90S ACROSS SOUTHEAST GEORGIA AS DEBRIS CLOUDINESS THINS
AND A CUMULUS FIELD DEVELOPS. THIS SHOULD ALLOW MAX HEAT INDICES
TO REACH THE 103-107 RANGE WELL INLAND WITH 108-112 SOUTH OF
I-16 AND UP ALONG SOUTH COASTAL SOUTH CAROLINA LATER THIS
AFTERNOON PRIOR TO THE ONSET OF CONVECTION. A HEAT ADVISORY
REMAINS IN EFFECT FOR ALL BUT THE FAR INTERIOR FROM 11 AM UNTIL
8 PM, ALTHOUGH THE ADVISORY IS LOOKING INCREASINGLY MORE
MARGINAL FOR CHARLESTON COUNTY AND COASTAL COLLETON COUNTY WHERE
THE DELAYED RISE IN TEMPERATURES AND A POSSIBLE EARLY START TO
CONVECTION MAY KEEP HEAT INDICES NEAR TO OR JUST SLIGHTLY BELOW
HEAT ADVISORY CRITERIA. DEPENDING ON RADAR AND SHORT TERM
TEMPERATURES TRENDS, PORTIONS OF THE HEAT ADVISORY MAY BE
CANCELLED WITH THE EARLY AFTERNOON ROUTINE FORECAST PACKAGE.
CONVECTION STILL LOOKS TO CONCENTRATE ACROSS THE INTERIOR LATER
TODAY, POSSIBLY WORKING CLOSER TO THE COAST LATE THIS AFTERNOON
INTO THIS EVENING PENDING MESOSCALE BOUNDARY INTERACTIONS. THE
PRIMARY CONCERNS ARE HEAVY RAIN/MINOR FLOODING WITH A FEW STRONG
TSTMS THROWN INTO THE MIX. TYPICAL FOR THIS TIME OF YEAR, AN
ISOLATED PULSE SEVERE TSTM WITH DAMAGING WINDS FROM DOWNBURSTS
CAN NOT BE COMPLETELY RULED OUT.
TONIGHT: CONVECTION IS EXPECTED TO DECREASE IN COVERAGE.
HOWEVER, GIVEN AMPLE MOISTURE AND PRESENCE OF INSTABILITY, IT IS
LIKELY THAT AT LEAST ISOLATED CONVECTION WILL PERSIST MUCH OF
THE NIGHT.
SHORT TERM /THURSDAY THROUGH SATURDAY/
THURSDAY AND FRIDAY: SUBTROPICAL RIDGE BEGINS TO WEAKEN BY LATE
WEEK, AS MULTIPLE SHORTWAVES ALOFT CARVE OUT A LONGER WAVE TROUGH
ACROSS THE EASTERN CONUS. THIS WILL SUPPORT A CONTINUED RISK FOR
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS EACH
AFTERNOON/EVENING. IN REGARD TO TEMPERATURES, LOOK FOR HIGHS TO
REMAIN IN THE MID TO UPPER 90S, WITH PERHAPS A FEW LOCATIONS ACROSS
SOUTHEASTERN GEORGIA FLIRTING WITH 100 DEGREES. SIMILAR TO DAYS
PAST, WILL SEE HEAT INDICES PEAK BETWEEN 105-108 DEGREES INLAND TO
108-112 DEGREES ALONG/EAST OF I-95 PRIOR TO THE ONSET OF ANY
CONVECTION. ADDITIONAL HEAT ADVISORIES MAY BE NEEDED, BUT THESE WILL
LARGELY BE DRIVEN BY THE TIMING AND EXTENT OF AFTERNOON CONVECTION -
SO STAY TUNED FOR FUTURE UPDATES!
SATURDAY: BROAD UPPER LEVEL TROUGH AND ITS ATTENDANT SFC COLD FRONT
CONTINUE TO SAG SOUTHEASTWARD ACROSS THE REGION FRIDAY NIGHT,
RESULTING IN A FAIRLY WET AND UNSETTLED PATTERN OVER THE WEEKEND.
WHILE SHOWERS AND STORMS WILL LIKELY BE ONGOING SATURDAY MORNING,
EXPECT THE BETTER CHANCES TO ARRIVE DURING THE AFTERNOON HOURS AS
INSTABILITY AND MOISTURE INCREASE. TEMPERATURES DURING THIS TIME
WILL ALSO BE NOTABLY COOLER, AS HIGHS ONLY RISE INTO THE MID 80S TO
LOWER 90S UNDER CLOUDY SKIES.
LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/
DREARY CONDITIONS CONTINUE SUNDAY AND MONDAY AS THE AFOREMENTIONED
FRONT STALLS ALONG THE COAST. WITH PWATS GREATER THAN 2 INCHES,
COULD CERTAINLY SEE PERIODS OF LOCALLY HEAVY RAINFALL, WHICH MAY
RESULT IN FLASH FLOODING. AS NOTED IN THE PREVIOUS DISCUSSION,
CONFIDENCE STILL REMAINS TOO LOW AT THIS TIME TO DETERMINE IF THE
RISK FOR FLASH FLOODING WILL BE WIDESPREAD ENOUGH TO WARRANT A FLOOD
WATCH. DO THINK IT'S WORTH NOTING, HOWEVER, THAT WPC'S LATEST 7 DAY
QPF FORECAST DOES HIGHLIGHT TOTALS POTENTIALLY REACHING 3 TO 5
INCHES ACROSS OUR AREA, WITH A BULK OF THOSE VALUES EXPECTED TO FALL
OVER A 3 DAY PERIOD (SATURDAY THROUGH MONDAY). CERTAINLY SOMETHING
TO KEEP AN EYE ON IN THE COMING DAYS, ESPECIALLY FOR THOSE FOLKS WHO
HAVE OUTDOOR PLANS! OTHERWISE, LOOK FOR SEASONALLY COOL TEMPERATURES
TO PREVAIL FOR THE REMAINDER OF THE EXTENDED PERIOD.
AVIATION /13Z WEDNESDAY THROUGH SUNDAY/
KCHS AND KJZI: EXPECT CONVECTION TO REDEVELOP THIS AFTERNOON
THEN PUSH INLAND LATER IN THE AFTERNOON/EVENING. FLIGHT
RESTRICTIONS POSSIBLE WITH ANY SHOWERS/THUNDERSTORMS THIS
AFTERNOON. EXPECT A RETURN TO VFR CONDITIONS AFTER 00Z 31 JULY.
KSAV: VFR CONDITIONS LIKELY TO PREVAIL THROUGH THIS MORNING. BY
AFTERNOON, SCATTERED TO NUMEROUS SHOWERS/THUNDERSTORMS ARE
EXPECTED. SO, HAVE KEPT TEMPO FOR CONVECTION THROUGH MID/LATE
AFTERNOON WITH FLIGHT RESTRICTIONS POSSIBLE. EXPECT RETURN TO
VFR AFTER 00Z 31 JULY.
EXTENDED AVIATION FORECAST: THE RISK FOR FLIGHT RESTRICTIONS DUE TO
SHOWERS/TSTMS WILL PERSIST EACH AFTERNOON/EVENING WITH CHANCES
RAMPING UP OVER THE WEEKEND.
MARINE
THROUGH TONIGHT: NO HIGHLIGHTS ARE EXPECTED. ATLANTIC HIGH
PRESSURE WILL REMAIN CENTERED SOUTHEAST OF THE WATERS, WITH AN
INLAND TROUGH OF LOW PRESSURE. GENERALLY SOUTHERLY WINDS OF 5-15
KTS, STRONGEST NEAR THE COAST IN THE AFTERNOON AS THE SEABREEZE
DEVELOPS. SEAS 2 TO 3 FEET, HIGHEST BEYOND 20 NM OFFSHORE OF
THE GA WATERS. SCATTERED MAINLY MORNING AND LATE NIGHT SHOWERS
AND THUNDERSTORMS.
THURSDAY THROUGH SUNDAY: SOUTHERLY WIND REGIME WILL PREVAIL
THROUGH FRIDAY. WINDS WILL BEGIN TO TURN NORTHEAST OVER THE
WEEKEND AS A COLD FRONT STALLS OUT NEAR THE AREA. WINDS WILL
GENERALLY REMAIN 15 KT OR LESS THROUGH THE PERIOD, ALTHOUGH
WINDS MAY GET AS HIGH AS 15- 20 KT OVER THE WEEKEND ACROSS
MAINLY THE SOUTH CAROLINA WATERS AS THE GRADIENT PINCHES A BIT
BEHIND THE COLD FRONT.
CLIMATE
RECORD HIGH MINIMUM TEMPERATURES:
JULY 31:
KCHS: 80/2022
KSAV: 80/2010
AUGUST 1:
KCHS: 81/1999
KSAV: 79/2020
CHS WATCHES/WARNINGS/ADVISORIES
GA...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR GAZ099>101-
114>119-137>141.
SC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR SCZ047>052.
MARINE...NONE.
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