A back door cold front in combination with a warm and unstable air mass, resulted in scattered strong to severe thunderstorms across southern South Carolina.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS CHS wrote it up.
A back door cold front in combination with a warm and unstable air mass, resulted in scattered strong to severe thunderstorms across southern South Carolina.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Charleston, SC wrote its last area forecast discussion before the first event at Apr 9, 9:14 PM EST, 51 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHARLESTON SC 1014 PM EDT SAT APR 9 2011 ...SEVERE THUNDERSTORMS POSSIBLE ACROSS THE CHARLESTON TRI-COUNTY AREA THROUGH EARLY MORNING SUNDAY... .SYNOPSIS... A WEAKENING BACKDOOR COLD FRONT WILL STALL OVER THE REGION TONIGHT AND WILL DISSIPATE SUNDAY. A STRONGER COLD FRONT IS FORECAST TO MOVE THROUGH MON NIGHT. WEAK HIGH PRES WILL THEN RETURN THROUGH MID WEEK. ANOTHER FRONT MAY AFFECT THE REGION NEXT WEEKEND. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... SEVERE TSTM WATCH 117 REMAINS IN EFFECT FOR BERKELEY-CHARLESTON AND DORCHESTER COUNTIES UNTIL 2 AM. THE 10 PM UPDATE FEATURES AN INCREASE IN POPS TO 50-70 PERCENT FOR THE TRI-COUNTY AREA WITH POPS LESS THAN 20 PERCENT FOR THE REMAINDER OF THE LOCAL FORECAST AREA. RADAR SHOWS SUPERCELLS LINED UP FROM THE PEE DEE UP INTO WESTERN NORTH CAROLINA AND STREAMING SOUTHEAST. THE GENERAL MOVEMENT OF THE MESOSCALE CONVECTIVE SYSTEM IS TO THE SOUTH...SO ACTIVITY CURRENTLY MOVING SOUTH OF CHARLOTTE AND EAST OF GREENVILLE- SPARTANBURG COULD BRUSH PARTS OF CHARLESTON-BERKELEY AND DORCHESTER COUNTIES OVER THE NEXT FEW HOURS. PRIMARY HAZARD WILL BE LARGE HAIL...BUT DAMAGING WINDS OR EVEN AN ISOLATED TORNADO CAN NOT BE COMPLETELY RULED OUT...HOWEVER THE STABLE POST-FRONTAL MARINE LAYER WILL LIKELY LIMIT THAT POTENTIAL. QUITE A BIT OF ELEVATED INSTABILITY IS IN PLACE ATOP THE COOL POST FRONTAL AIRMASS...SO TSTMS SHOULD PERSIST DESPITE THE LACK OF SIGNIFICANT SURFACE BASED INSTABILITY. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/... SUNDAY AND SUNDAY NIGHT...DRY AND WARM CONDITIONS WILL PREVAIL AS AN UPPER LEVEL RIDGE AXIS EXTENDS NORTHEAST FROM THE GULF OF MEXICO OVER THE EASTERN SEABOARD. THICKNESSES SUPPORT HIGHS IN THE LOW-MID 80S N TO MID-UPR 80S S. SHOULD ENOUGH CLOUD COVER REMAIN TOMORROW FROM CONVECTION SATURDAY NIGHT...TEMPS COULD BE A FEW DEGREES COOLER. THE RIDGE AXIS WILL SLOWLY PUSH OFFSHORE SUN NIGHT...ALLOWING FOR MOSTLY CLEAR SKIES BUT CONTINUED MILD NIGHTTIME TEMPS. WILL LOOK FOR LOWS IN THE MID 60S. MONDAY THROUGH TUESDAY...DEEP RIDGING WILL SHIFT OFFSHORE MONDAY... MAKING FOR DEEP SOUTHWESTERLY FLOW DURING THE DAY ON MONDAY AHEAD OF A COLD FRONT DUE TO ARRIVE ON TUESDAY. THOUGH THERE WILL BE SOME AFTN CUMULUS DEVELOPMENT MONDAY...ANY CONVECTIVE DEVELOPMENT WILL BE IMPEDED BY MODEST UPPER SUBSIDENCE SO WILL KEEP THE FORECAST DRY. ANOTHER WARM DAY IS EXPECTED WITH THICKNESSES SUPPORTING HIGHS IN THE UPPER 80S TO AROUND 90. THE COLD FRONT WILL ENTER FAR WESTERN PORTIONS OF THE CHS CWFA DURING THE PRE-DAWN HOURS TUESDAY MORNING THEN CONTINUE PUSHING TOWARD THE COAST AND OFFSHORE BY MID-AFTERNOON TUESDAY. THE FRONT IS BEING ENHANCED ALOFT BY A DIGGING TROUGH AXIS EXTENDING SW FROM THE EASTERN GREAT LAKES THROUGH THE LOWER MISSISSIPPI RIVER VALLEY. MOISTURE SWATH WITH THE FRONT IS RATHER LIMITED...CONFINED TO THE FRONT ITSELF...SO THERE LOOKS TO BE A NARROW WINDOW FOR FRONTAL SHWRS/TSTMS LATE MON NIGHT INTO TUE MORNING. SFC HIGH PRESSURE WILL THEN SETTLE OVER THE SOUTHEAST IN WAKE OF THE FRONT FOR DURING THE DAY TUESDAY. HIGH TEMPS WILL BE AROUND 80. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... ATLANTIC HIGH PRESSURE WILL KEEP HOLD OVER THE SOUTHEAST THROUGH MIDWEEK. LITTLE TO NO CHANCE OF PRECIP IS ANTICIPATED THROUGH THURSDAY. OVERALL HIGH TEMPS WILL BE IN THE UPPER 70S TO AROUND 80 OVER SOUTHERN PORTIONS OF SOUTHEAST GEORGIA. OVERNIGHT LOWS WILL BE IN THE UPPER 50S. TEMPS MAY SLIGHTLY WARM AS WE HEAD INTO THE WEEKEND AS ANOTHER SYSTEM DEVELOPS OVER THE PLAINS AND TRACKS EAST. FRIDAY AND SATURDAY...WIDESPREAD ISENTROPIC ASCENT WILL PRODUCE CLOUD COVER THAT WILL LIMIT HIGH TEMPS TO THE UPPER 70S DESPITE SOUTHERLY FLOW AHEAD OF A LOW PRESSURE SYSTEM TRACKING THROUGH THE MIDWEST. CHANCES OF PRECIP WILL INCREASE FRIDAY EVENING THROUGH SATURDAY MORNING AS A TRAILING COLD FRONT PASSES THROUGH THE SOUTHEAST. HAVE INCREASED POPS TO CHANCE DURING THE EXPECTED TIME OF COLD FROPA. DRY CONDITIONS SHOULD RETURN LATE THIS WEEKEND AS HIGH PRESSURE SETTLES OVER THE SOUTHEAST. OVERALL HIGHS WILL REMAIN IN THE UPPER 70S/LOWER 80S. && .AVIATION /02Z SUNDAY THROUGH THURSDAY/... EXPECT DETERIORATING CONDITIONS THROUGH THE NIGHT AT BOTH KCHS AND KSAV AS A BACKDOOR FRONT STALLS OVER THE AREA AND DEVELOPING UPSTREAM CONVECTION PROPAGATES EASTWARD TOWARD THE COAST. AT KCHS IFR CEILINGS HAVE ALREADY SETTLED IN WHICH WILL LIKELY PREVAIL THROUGH EARLY SUNDAY MORNING...HOWEVER WILL MAINTAIN VFR CEILINGS AT KSAV DUE TO THE PLACEMENT OF THE FRONT. STILL...VISIBILITIES WILL LIKELY DROP TO IFR OR LOWER LEVELS AT BOTH SITES AS PATCHY FOG DEVELOPS OVERNIGHT DUE TO PLENTY OF LINGERING LOW LEVEL MOISTURE. MEANWHILE...UPSTREAM THUNDERSTORMS COULD STILL ADVANCE SE AND IN THE VICINITY OF KCHS AFTER 03Z. DUE TO LACK OF COVERAGE AND LOW CONFIDENCE THAT THE TERMINAL WILL BE DIRECTLY IMPACTED...WILL KEEP ANY MENTION OF TSRA OUT OF TAFS. WILL AMEND AS NECESSARY TO ADDRESS NEAR TERM CONVECTION TRENDS. EXTENDED AVIATION OUTLOOK...MVFR CONDITIONS POSSIBLE MON NIGHT THROUGH TUE MORNING AS A COLD FRONT SHIFTS THROUGH THE REGION. OTHERWISE...VFR. && .MARINE... THUNDERSTORMS COULD PRODUCE LOCALLY STRONG WINDS AND HAZARDOUS CONDITIONS TONIGHT. OTHERWISE...A COLD FRONT WILL WEAKEN AND STALL OVER THE SC WATERS THIS EVENING. INITIAL SURGE OF E/NE WINDS AS HIGH AS 15-20 KT ACROSS SC WATERS N OF EDISTO BEACH WILL GIVE WAY TO A WEAKENING PRESSURE PATTERN/DIMINISHING WINDS OVERNIGHT. ALONG AND S/SW OF THE BOUNDARY...A WEAK PRESSURE PATTERN WILL FAVOR VARIABLE WINDS 10 KT OR LESS TONIGHT. SEAS WILL REMAIN 1-3 FT ACROSS THE COASTAL WATERS TONIGHT. SUNDAY THROUGH WEDNESDAY...CONDITIONS WILL REMAIN WELL BELOW SCA CRITERIA SUN AND MON. ATLC HIGH PRES WILL BEGIN TO SHIFT E AS A LOW PRES SYSTEM TRACKS THROUGH THE EASTERN CONUS. SOUTHERLY FLOW SUN WILL BEGIN TO INCREASE MON AS A COLD FRONT APPROACHES FROM THE W. MODELS HAVE BACKED OFF THE STRENGTH OF THE PINCHED GRADIENT WITH THE FRONT MON NIGHT SO HAVE KEPT CONDITIONS BELOW SCA LEVELS. WINDS ARE ANTICIPATED TO INCREASE TO 15-20 KT WHILE SEAS BUILD TO 6 FT FOR WATERS JUST BEYOND 20 NM FROM THE COAST. CONDITIONS WILL THEN IMPROVE QUICKLY TUESDAY MORNING THROUGH LATE WEEK AS THE FRONT DRIFTS WELL OFFSHORE AND HIGH PRESSURE SETTLES OVER THE WATERS. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...NONE. MARINE...NONE. &&
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE CHARLESTON SC 828 PM EDT SAT APR 9 2011 AMZ330-350-SCZ044-045-050-052-110030- CHARLESTON HARBOR- WATERS FROM SOUTH SANTEE RIVER TO EDISTO BEACH SC OUT 20 NM- DORCHESTER-INLAND BERKELEY-CHARLESTON-TIDAL BERKELEY- 828 PM EDT SAT APR 9 2011 ...SEVERE THUNDERSTORM WATCH 117 IN EFFECT UNTIL 2 AM EDT SUNDAY... THIS HAZARDOUS WEATHER OUTLOOK IS FOR ATLANTIC COASTAL WATERS AND SOUTHEAST SOUTH CAROLINA. .DAY ONE...TONIGHT. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. SEVERE THUNDERSTORM WATCH. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY. NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED LATER THIS EVENING. AMZ352-354-374-GAZ087-088-099>101-114>119-137>141-SCZ040-042-043- 047>049-051-110030- WATERS FROM EDISTO BEACH SC TO SAVANNAH GA OUT 20 NM- WATERS FROM SAVANNAH GA TO ALTAMAHA SOUND GA OUT 20 NM...INCLUDING GRAYS REEF NATIONAL MARINE SANCTUARY- WATERS FROM SAVANNAH GA TO ALTAMAHA SOUND GA EXTENDING FROM 20 TO 60 NM-JENKINS-SCREVEN-CANDLER-BULLOCH-EFFINGHAM-TATTNALL-EVANS- INLAND BRYAN-COASTAL BRYAN-INLAND CHATHAM-COASTAL CHATHAM-LONG- INLAND LIBERTY-COASTAL LIBERTY-INLAND MCINTOSH-COASTAL MCINTOSH- ALLENDALE-HAMPTON-INLAND COLLETON-INLAND JASPER-BEAUFORT- COASTAL COLLETON-COASTAL JASPER- 828 PM EDT SAT APR 9 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR ATLANTIC COASTAL WATERS...SOUTHEAST GEORGIA AND SOUTHEAST SOUTH CAROLINA. .DAY ONE...TONIGHT. NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY. NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.
The Columbia radar (KCAE), 104 km away, was scanning. The volume nearest the first event began at 03:04 UTC.
9 hail, 2 thunderstorm wind. Local standard time, as filed.
A thunderstorm wind gust of 64 miles per hour was measured.
Law enforcement reported quarter to golf ball size hail in Pineville, South Carolina.
A spotter reported golf ball to tennis ball size hail near Russellville, South Carolina.
A spotter reported nickel size hail.
Fire department personnel reported golf ball size hail between Saint Stephen and Bonneau.
The public reported quarter to half dollar size hail near Bonneau.
Fire department personnel reported trees down between Bonneau and Saint Stephen.
A spotter reported golf ball size hail east of Bonneau, Georgia.
A spotter reported golf ball size hail east of Bonneau, Georgia.
The public reported golf ball size hail for 10 to 15 minutes in the Macedonia area.
A spotter reported quarter to half dollar size hail completely covering the ground.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in South Carolina in 2011Every state in 2011This day in weather historyWarnings in South Carolina, April 2011
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 303677, 303674, 303673, 303672, 303670, 303671, 303676, 303667, 303668, 303669, 303666.