688
FXUS62 KCHS 292337
AFDCHS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
737 PM EDT THU MAY 29 2025
SYNOPSIS
A STORM COMPLEX OVER THE DEEP SOUTH WILL TRACK OVER THE AREA
THIS EVENING, THEN A COLD FRONT WILL SWEEP THROUGH LATE FRIDAY.
HIGH PRESSURE WILL BUILD IN OVER THE WEEKEND INTO EARLY NEXT
WEEK.
NEAR TERM /UNTIL 6 AM FRIDAY MORNING/
EARLY THIS EVENING: CONVECTION INITIATED EARLY ACROSS THE
FORECAST AREA THIS AFTERNOON AND IMPACTED MOST OF THE AREA
EXCEPT FOR SOUTHEAST GA. MUCH OF THE AREA IS NOW LIKELY WORKED
OVER AND GIVEN THE AMOUNT OF MID AND HIGH LEVEL CLOUDS IN PLACE,
INSTABILITY IS EITHER WEAK OR NON-EXISTENT. IN FACT, RADAR
IMAGERY SHOWS THAT THE FOCUS FOR NEW CONVECTION HAS SHIFTED
OFFSHORE WHERE THERE ARE SOME RATHER ROBUST STORMS. THE FORECAST
THROUGH THE OVERNIGHT IS TRICKY AS HI-RES MODEL SOLUTIONS ARE
REALLY ALL OVER THE PLACE WITH THE COVERAGE AND INTENSITY OF
SHOWERS AND THUNDERSTORMS. GUIDANCE DOES SUGGEST THAT THERE IS
SOME MID-LEVEL SHORTWAVE ENERGY POISED TO STILL PASS THROUGH
INTO THE EARLY MORNING HOURS, AND THAT COULD BE ENOUGH TO KICK
OFF ANOTHER ROUND OF CONVECTION LATER THIS EVENING. FOR NOW, THE
FORECAST FAVORS THE COAST AND THE ADJACENT COASTAL WATERS FOR
THE BEST CHANCES OVERNIGHT, WITH JUST 20-30 PERCENT CHANCES
ACROSS LAND AREAS. AS WITH ANYTIME THERE IS AFTERNOON/EVENING
CONVECTION, ATTENTION TURNS TO FOG AND STRATUS CLOSER TO SUNRISE
FRIDAY. MUCH LIKELY LAST NIGHT, WE WILL FAVOR MORE STRATUS THAN
FOG.
SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/
FRIDAY: A LONGWAVE UPPER TROUGH WITH AN EMBEDDED SHORTWAVE WILL
APPROACH THE SOUTHERN MID-ATLANTIC AND CAROLINAS, WHICH WILL
EVENTUALLY PUSH A COLD FRONT THROUGH THE AREA FRIDAY NIGHT.
MOISTURE SEEMS TO BE ON A DOWNWARD TREND THE LAST FEW DAYS,
HOWEVER STILL EXPECTING PWATS TO INCREASE FROM 1.3 INCHES IN THE
MORNING TO AROUND 1.75 INCHES BY LATE AFTERNOON AHEAD OF THE
FRONT. SIMILARLY, MLCAPE VALUES HAVE DECREASED BUT ARE EXPECTED
TO PEAK AROUND 800-900 J/KG. WIND FIELDS ARE FAIRLY STRONG
THOUGH WITH 0-6 KM BULK SHEAR OF 35-45 KT. THERE COULD BE SOME
RESIDUAL SHOWERS FROM THE PREVIOUS NIGHT LINGERING MAINLY
OFFSHORE OR ALONG THE COAST IN THE MORNING HOURS, HOWEVER MOST
LOCATIONS OVER LAND LOOK RAIN-FREE WITH SOUNDINGS SHOWING DECENT
SUBSIDENCE. MODELS DEPICT A LINE OF SCATTERED SHOWERS AND
THUNDERSTORMS WITH SOME ORGANIZATION APPROACHING FROM THE
NORTHWEST, SWEEPING THROUGH THE AREA FRIDAY AFTERNOON/EVENING. A
FEW STORMS COULD BECOME SEVERE WITH DAMAGING WINDS AND LARGE
HAIL. THERE ARE ALSO SIGNALS THAT THE LINE OF STORMS COULD
WEAKEN AS THEY MARCH EASTWARD TOWARD THE COAST AS THE
ORIENTATION OF THE FRONT BECOMES SLIGHTLY MORE ALIGNED PARALLEL
TO THE FLOW. REGARDLESS, RAINFALL SHOULD COME TO AN END BY LATE
EVENING. TEMPERATURES WILL PEAK IN THE MID TO UPPER 80S BEFORE
THE ONSET OF CONVECTION, BECOMING RELATIVELY COOL OVERNIGHT;
DROPPING INTO THE UPPER 50S FAR INLAND AND LOWER TO MIDDLE 60S
ELSEWHERE.
SATURDAY AND SUNDAY: A DISTINCTLY DRIER AIR MASS WILL MOVE INTO
THE AREA IN THE WAKE OF THE FRONT SATURDAY. MOSTLY SUNNY SKIES
ARE EXPECTED BOTH DAYS IN ADDITION TO DEW POINTS DIPPING INTO
THE 50S DURING PRIME AFTERNOON MIXING HOURS. HIGHS POST FROPA
WILL PEAK IN THE LOW TO MID 80S SATURDAY AND A DEGREE OR TWO
WARMER FOR SUNDAY. SATURDAY NIGHT LOW TEMPS WILL REACH THE LOWER
TO MIDDLE 60S AWAY FROM THE IMMEDIATE COAST.
LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/
A REINFORCING COLD FRONT COULD MOVE THROUGH LATE SUNDAY INTO
MONDAY, POTENTIALLY ACCOMPANIED BY A POTENT UPPER SHORTWAVE
SLIDING BY TO OUR SOUTH. THERE IS A SMALL CHANCE (LESS THAN 20%)
THIS COULD BRING SOME SHOWERS TO THE AREA, HOWEVER MOISTURE
WILL BE LIMITED WITH WEAK SURFACE HIGH PRESSURE STILL IN PLACE.
THEREAFTER, RIDGING ALOFT WILL TAKE SHAPE RESULTING IN MOSTLY
DRY WEATHER AND A GRADUAL WARMING TREND THROUGHOUT NEXT WEEK.
AVIATION /00Z FRIDAY THROUGH TUESDAY/
THE 00Z TAF PERIOD BEGINS WITH VFR CONDITIONS IN PLACE AND NO
IMMEDIATE CONCERNS FOR SHOWERS OR THUNDERSTORMS AT KCHS, KJZI,
AND KSAV. THE FIRST FORECAST CONCERN IS ONCE AGAIN THE POTENTIAL
FOR LOWER CEILINGS AND VISIBILITIES LATE TONIGHT. WE WILL AGAIN
FAVOR STRATUS OVER FOG AND ADVERTISE A PERIOD OF IFR CEILINGS AT
ALL 3 SITES IN THE 10-14Z TIME PERIOD. ANOTHER ROUND OF
THUNDERSTORMS IS EXPECTED LATE FRIDAY AFTERNOON AND WE HAVE
ADDED VCTS IN AT ALL 3 SITES STARTING AROUND 21-22Z.
EXTENDED AVIATION OUTLOOK: VISIBILITY REDUCTIONS POSSIBLE
THROUGH FRIDAY EVENING, MAINLY IN SHOWERS AND THUNDERSTORMS.
OUTSIDE OF CONVECTION, GUSTS UP TO 20 KT ARE POSSIBLE FRIDAY AND
AGAIN SATURDAY AFTERNOON.
MARINE
TONIGHT: THE WEATHER PATTERN WILL SUPPORT SOUTHERLY WINDS
BETWEEN 10 TO 15 KTS WITH SOME GUST. SEAS ARE FORECAST TO RANGE
BETWEEN 2 TO 3 FT TONIGHT. SPECIAL MARINE WARNINGS MAY BE NEEDED
ACROSS THE CHS HARBOR AND ATLANTIC WATERS THROUGH THIS EVENING,
WIND GUSTS AROUND 35 KTS POSSIBLE WITH THESE STORMS.
FRIDAY THROUGH TUESDAY: SW WINDS WILL BEGIN TO INCREASE FRIDAY
AHEAD OF A COLD FRONT. GUSTS COULD REACH 25 KT LATE AFTERNOON
AND CONTINUE INTO THE OVERNIGHT PERIOD. SMALL CRAFT ADVISORIES
COULD BE NEEDED FOR THE CHARLESTON COUNTY NEARSHORE WATERS,
INCLUDING THE CHARLESTON HARBOR, AND THE OUTER GEORGIA WATERS
FROM 20-60 NM. ELEVATED WSW WIND GUSTS ARE POSSIBLE AGAIN
SATURDAY, BUT SHOULD STAY BELOW 25 KT. IMPROVEMENT SHOULD BE
UNDERWAY SATURDAY NIGHT WITH NO ADDITIONAL MARINE CONCERNS
THROUGH THE PERIOD.
CHS WATCHES/WARNINGS/ADVISORIES
GA...NONE.
SC...NONE.
MARINE...NONE.
NEAR TERM...BSH
SHORT TERM...BRS
LONG TERM...BRS
AVIATION...BRS/BSH
MARINE...BRS/NED
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page