675
FXUS62 KCHS 211819
AFDCHS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
219 PM EDT THU MAY 21 2026
WHAT HAS CHANGED
ALL SECTIONS HAVE BEEN UPDATED.
KEY MESSAGES
- 1) INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS THIS WEEKEND,
THOUGH NO HAZARDOUS WEATHER IS ANTICIPATED AT THIS TIME.
DISCUSSION
KEY MESSAGE 1: INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS THIS
WEEKEND, THOUGH NO HAZARDOUS WEATHER IS ANTICIPATED AT THIS TIME.
ALOFT, A TROUGH CENTERED OFF THE SOUTHEAST COAST WILL GRADUALLY SLIP
FURTHER AWAY FROM THE REGION ACROSS THE ATLANTIC TODAY, WELL IN
ADVANCE OF H5 VORT ENERGY RIPPLING ACROSS THE DEEP SOUTH AND
SOUTHEAST UNITED STATES THIS WEEKEND. AT THE SFC, A COLD FRONT
POSITIONED NEAR THE TENNESSEE RIVER VALLEY TODAY WILL SLOWLY SAG
EAST-SOUTHEAST TO THE CAROLINAS BY FRIDAY, LIKELY STALLING NORTH OF
THE LOCAL AREA BEFORE DEPARTING WELL TO THE NORTH/NORTHEAST LATE
WEEKEND. LIGHT ONSHORE/SOUTHERLY FLOW AND AMPLE SUNSHINE SOUTH OF
THIS FEATURE SHOULD PROVIDE MOISTURE AND HEATING NECESSARY FOR
SUMMER-LIKE CONVECTION ACROSS THE SOUTHEAST, WITH FAIRLY UNORGANIZED
SHOWER AND THUNDERSTORM ACTIVITY LOCALLY GIVEN THE LACK OF DEEP-
LAYERED SHEAR. INSTABILITY SHOULD BE SUFFICIENT FOR FEW TO SCATTERED
SHOWERS/THUNDERSTORMS TO DEVELOP EACH AFTERNOON, PERHAPS INITIALLY
ALONG A SEA BREEZE CIRCULATION, BEFORE BECOMING MORE NUMEROUS ACROSS
INLAND AREAS AS H5 VORT ENERGY RIPPLES ACROSS THE VICINITY DURING
PEAK DIURNAL HEATING HOURS. SEVERE WEATHER CHANCES SHOULD REMAIN LOW
THROUGH THE WEEKEND, ALTHOUGH A FEW STRONGER THUNDERSTORMS WITH
GUSTY WINDS CAN NOT BE RULED OUT EACH AFTERNOON/EVENING.
RAINFALL AMOUNTS SHOULD REMAIN ON THE LIGHTER SIDE WITH MOST
ACTIVITY THIS WEEKEND, ALTHOUGH SOME LOCATIONS COULD SEE 0.5 TO 1
INCH TOTAL RAINFALL ACCUMULATION ALONG/WEST OF I-95. THE RISK FOR
MINOR FLOODING IS LOW WITH THE ANTICIPATED SETUP. HOWEVER, ANY
RAINFALL EXPERIENCED DURING THE DAY COMBINED WITH SFC DEWPTS IN THE
UPPER 60S/LOWER 70S AND LIGHT/CALM WINDS AT NIGHT COULD SUPPORT
PATCHY FOG/SHALLOW GROUND FOG AWAY FROM THE COAST EACH MORNING THIS
WEEKEND.
AN UNSETTLED PATTERN LOOKS TO CONTINUE NEXT WEEK, THOUGH CONFIDENCE
IN LOCATION AND RAINFALL AMOUNTS REMAINS LOW GIVEN CONVECTION IS
DIURNALLY DRIVEN IN NATURE (SUMMER-LIKE). HOWEVER, THE BULK OF
PRECIP ACTIVITY TENDS TO OCCUR INLAND TO A SEA BREEZE SHIFTING
INLAND EACH DAY. OTHERWISE, LOOK FOR AFTERNOON HIGHS IN UPPER 80S TO
LOWER 90S, WITH MILD OVERNIGHT LOWS IN THE UPPER 60S TO 70S.
AVIATION /18Z THURSDAY THROUGH TUESDAY/
VFR CONDITIONS SHOULD PREVAIL AT CHS/JZI/SAV TERMINALS THROUGH 18Z
FRIDAY. SOUTH/SOUTHEAST WINDS SHOULD GUST UP TO 15-18 KT WITH A SEA
BREEZE THIS AFTERNOON. PATCHY FOG IS POSSIBLE LATE TONIGHT AND/OR
JUST PRIOR TO DAYBREAK FRIDAY, BUT CONFIDENCE IS TOO LOW TO INCLUDE
AT THE TERMINALS FOR THE LATEST TAF ISSUANCE. A FEW SHOWERS AND/OR
ISOLATED THUNDERSTORM COULD IMPACT THE TERMINALS WITH A SEA BREEZE
LATE MORNING/EARLY AFTERNOON FRIDAY. HOWEVER, CONFIDENCE IS TOO LOW
TO INCLUDE IN THE LATEST TAF ISSUANCE.
EXTENDED AVIATION OUTLOOK: TEMPO FLIGHT RESTRICTIONS POSSIBLE WITH
SHOWERS AND THUNDERSTORMS AT CHS/JZI/SAV TERMINALS EACH AFTERNOON
THIS WEEKEND INTO EARLY NEXT WEEK.
MARINE
THIS AFTERNOON AND TONIGHT: A SOUTHERLY FLOW REGIME REMAINS IN
PLACE WITH AN UPPER TROUGH DRIFTING FURTHER OFFSHORE AND WEAK
SFC HIGH PRESSURE IN PLACE. WINDS AND SEAS WILL REMAIN WELL
BELOW SMALL CRAFT ADVISORY LEVELS, ALTHOUGH SOME ENHANCEMENT TO
WIND SPEEDS IS EXPECTED ALONG THE LAND/SEA INTERFACE WHERE A SEA
BREEZE SHIFTS INLAND. THIS INCLUDES THE CHARLESTON HARBOR WHERE
WINDS TOP OUT NEAR 15-20 KT THIS AFTERNOON. SOUTHERLY WINDS
AROUND 10 KT OR LESS ARE THEN ANTICIPATED OVERNIGHT. SEAS WILL
GENERALLY AVERAGE BETWEEN 2-4 FT.
FRIDAY THROUGH MONDAY: CONDITIONS ARE FORECAST TO REMAIN BELOW
SMALL CRAFT ADVISORY CRITERIA THROUGH THE WEEKEND. HIGH PRESSURE TO
THE EAST WILL DRIVE ONSHORE ESE FLOW EACH DAY, WITH WIND SPEEDS
MOSTLY TOPPING OUT IN THE 10-15 KNOT RANGE. EACH AFTERNOON AND
EVENING THERE COULD BE SOME LOCAL ENHANCEMENT ALONG THE LAND/SEA
INTERFACE WITH THE DIURNAL SEA BREEZE. SEAS WILL AVERAGE 2-4 FEET
THROUGH THE PERIOD.
RIP CURRENTS: A MODEST EASTERLY SWELL AROUND 3FT/9S AND SEA BREEZE
INFLUENCES EACH AFTERNOON WILL KEEP THE RIP CURRENT RISK IN THE
MODERATE CATEGORY THIS AFTERNOON THROUGH SATURDAY.
CHS WATCHES/WARNINGS/ADVISORIES
GA...NONE.
SC...NONE.
MARINE...NONE.
CPM/DPB
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page