Short wave moving in from NW, surface wave inland and plentiful mesoscale boundaries yet again. Storms developed into clusters and pushed off to the east and southeast.
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.
Short wave moving in from NW, surface wave inland and plentiful mesoscale boundaries yet again. Storms developed into clusters and pushed off to the east and southeast. DCAPES not as high as recent days, but still supportive of strong wet microbursts.
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 Jul 30, 12:42 PM EST, 1 hour 24 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHARLESTON SC 142 PM EDT MON JUL 30 2012 .SYNOPSIS... ATLANTIC HIGH PRESSURE WILL PREVAIL THROUGH THE WEEK WHILE A TROUGH OF LOW PRESSURE LINGERS INLAND. EXPECT A SERIES OF WEAK UPPER LEVEL DISTURBANCES TO SWING ACROSS THE AREA THROUGH MID WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... A VERY COMPLEX YET INTERESTING PATTERN IS IN PLACE THIS MORNING. WE HAVE STARTED THE DAY WITH MUCH MORE CLOUD COVER THAN THE LAST FEW MORNINGS WHICH IS LIMITING OUR LATE MORNING INSOLATION AND TEMPERATURE RISE. A POTENT SURFACE TROUGH AND ASSOCIATED MESOSCALE LOW PRESSURE AREA ARE IN PLACE ACROSS THE FORECAST AREA WITH THE LOW QUITE EVIDENT IN THE SWIRL ON VISIBLE SATELLITE OVER EAST CENTRAL GA. A SHORTWAVE TROUGH IS CURRENTLY MOVING OFF THE COAST AND HAS BEEN RESPONSIBLE FOR TRIGGERING SEVERAL INTENSE CLUSTERS OF THUNDERSTORMS OVER OUR COASTAL WATERS. 12Z UPPER AIR ANALYSIS SHOWS A COUPLED UPPER JET OVERHEAD WITH THE UPPER DIVERGENCE CENTERED OVER OUR COASTAL WATERS. THESE FEATURES ARE STILL TRIGGERING ADDITIONAL SHOWERS AND TSTMS OVER THE WATERS BUT MUCH OF THIS ACTIVITY SHOULD REMAIN OFFSHORE AND DIMINISH IN COVERAGE THROUGH EARLY THIS AFTERNOON. THE EXTENSIVE MID AND HIGH CLOUDINESS THAT EXISTS ACROSS THE EASTERN PORTIONS OF THE AREA SHOULD MOVE OFF TO THE EAST ALONG WITH THE CONVECTION. HOWEVER...A JUICY LOW-LEVEL ENVIRONMENT WITH PW/S ON THE 12Z CHS SOUNDING OF 2.15" AND EXTENSIVE MOISTURE CONVERGENCE ASSOCIATED WITH THE INLAND SURFACE LOW ARE RESPONSIBLE FOR BROKEN STRATUS AND STRATOCUMULUS IN MANY AREAS. PREDICTING THE EVOLUTION OF THIS LOW CLOUDINESS IS TRICKY. ALTHOUGH THE ATMOSPHERE IS MOISTURE-LADEN AT PRESENT...MODEL SOUNDINGS DO SHOW SUBSTANTIAL DRYING IN THE 900-600 MB LAYER THIS AFTERNOON. ADDITIONALLY...WEAK NVA BEHIND THE DEPARTING SHORTWAVE COULD CAUSE ENOUGH SUBSIDENCE TO HELP CLEAR OUT SOME OF THIS CLOUDINESS AND ALLOW FOR A BIT MORE DIABATIC HEATING THAN WE ARE SEEING NOW. TEMPERATURES EXPECTED TO CLIMB INTO THE LOWER 90S FAR INLAND BY MID-AFTERNOON WITH VALUES IN THE UPPER 80S TO NEAR 90 FARTHER EAST. ALTHOUGH THE UPPER JET DIVERGENCE IS PROGGED TO SHIFT EAST OF THE AREA TODAY...WE ARE WATCHING A POTENT SHORTWAVE CURRENTLY DROPPING SOUTHEAST OUT OF THE SOUTHERN APPALACHIANS. PVA ASSOCIATED WITH THIS FEATURE IS PROGGED TO SHIFT INTO OUR AREA LATE THIS AFTERNOON INTO THE EARLY EVENING. ASSUMING WE ERODE SOME OF THE LOW CLOUDS AND SOME DRIER AIR ADVECTS INTO THE MID-LEVELS...THE ENVIRONMENT COULD BE FAVORABLE FOR SOME MULTICELLULAR STORM CLUSTERS AND ANOTHER ROUND OF SEVERE WEATHER. THE LIMITING FACTOR TODAY IS DEFINITELY THE CLOUD COVER THAT WAS NOT AROUND YESTERDAY MORNING. THUS LOW-LEVEL THETA-E WILL NOT NEARLY BE WHAT WE SAW YESTERDAY SO THIS COULD TEND TO LIMIT THE WIDESPREAD NATURE OF THE SEVERE WEATHER THREAT. THE SEVERE THREAT WILL LIKELY RAPIDLY EVOLVE BASED ON MESOSCALE BOUNDARY INTERACTIONS SO WE WILL CONTINUE TO MENTION IN THE HAZARDOUS WEATHER OUTLOOK. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/... THROUGH SUNSET...CONVECTIVE RAINS WILL CONTINUE OVER THE REGION LIKELY BUILDING OVER INLAND GEORGIA ZONES LATE AS BOUNDARIES EDGE FURTHER WSW. IT IS A LITTLE UNCLEAR HOW MUCH INSTABILITY WILL BE LEFT LATER THIS EVENING AND OVERNIGHT BUT THE SURFACE WAVE SHOULD SLIDE TO THE N OF CHARLESTON AND LOW LEVEL MOISTURE CONVERGENCE IS EXPECTED TO EBB. WE MAINTAINED TRENDS OF DECREASING POPS OVERNIGHT LEAVING SOME NEAR COASTAL POPS AFTER MIDNIGHT. LOWS IN THE LOWER 70S AND MAYBE A LITTLE PATCHY LIGHT FOG LOCALLY... ESPECIALLY INLAND. TUESDAY THROUGH WEDNESDAY...THE BROAD UPPER TROUGH WILL CONTINUE TO MAINTAIN CONTROL ACROSS THE EASTERN UNITED STATES WHILE A STRONG UPPER RIDGE REMAINS ACROSS THE MIDDLE OF THE COUNTRY. MODELS SHOWS AN IMPRESSIVE UPPER DISTURBANCE TRACKING TOWARD THE CWA ON TUESDAY. EXPECT THIS SYSTEM TO BRING AT LEAST THE POTENTIAL FOR SCATTERED CONVECTION WHICH WILL LIKELY DEVELOP ACROSS INLAND AREAS FIRST BEFORE PROPAGATING EASTWARD TOWARD COASTAL COUNTIES. MODEL SOUNDINGS SHOW A BIT OF DRY AIR ALOFT EARLY TUESDAY...BUT PWATS WILL QUICKLY CLIMB TO OVER 2 INCHES BY LATE AFTERNOON. A FEW THUNDERSTORMS COULD BECOME STRONG OR SEVERE WITH DAMAGING WINDS AND FREQUENT LIGHTNING THE PRIMARY THREATS. MODELS ARE IN FAIRLY GOOD AGREEMENT THAT SOME SHORTWAVE ENERGY ALONG WITH PLENTY OF LINGERING DEEP MOISTURE WILL RESIDE OVER THE AREA THROUGH LATE TUESDAY NIGHT AND INTO EARLY WEDNESDAY MORNING. THIS COULD RESULT IN THE CONTINUATION OF SOME LATE NIGHT CONVECTION. IF TIMING OF THE MODELS IS CORRECT...THEN BY WEDNESDAY AFTERNOON THE BULK OF THE MOISTURE ASSOCIATED WITH THIS SYSTEM SHOULD BE MAINLY OFFSHORE. TEMPERATURES FOR BOTH DAYS WILL REFLECT SEASONAL NORMALS WITH HIGHS TOPPING OUT IN THE LOW TO MID 90S AND LOWS DIPPING INTO THE LOW TO MID 70S. THURSDAY LOOKS TO BE MORE OF A TRANSITION DAY AS THE UPPER TROUGH BEGINS TO WEAKEN AND THE UPPER RIDGE OVER THE MIDDLE OF THE UNITED STATES BEGINS TO BUILD EASTWARD. STILL...SOME ISOLATED TO SCATTERED CONVECTION IS EXPECTED TO DEVELOP DURING THE TRADITIONAL AFTERNOON/EARLY EVENING HOURS AS THE SEA BREEZE TRACKS INLAND. THUS...HAVE MAINTAINED CHANCE POPS...BUT EXPECT MUCH LESS COVERAGE THAN PREVIOUS DAYS. && .LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/... THE UPPER TROUGH ACROSS THE EASTERN STATES WILL CONTINUE TO WEAKEN AS THE UPPER RIDGE BUILDS EASTWARD TOWARD THE REGION. THE FORECAST AREA WILL BECOME POSITIONED BETWEEN THE SURFACE HIGH PRESSURE TO THE WEST AND THE ATLANTIC HIGH PRESSURE BY THE WEEKEND. DURING THIS TRANSITION...THE PATTERN WILL BE MUCH LESS EFFECTIVE AT GENERATING PRECIPITATION. THEREFORE...HAVE POPS GENERALLY CAPPED AT 20 PERCENT FOR EACH AFTERNOON WHILE DRY CONDITIONS WILL LIKELY PERSIST DURING THE OVERNIGHT PERIODS. TEMPERATURES WILL REFLECT NORMAL SUMMERTIME HIGHS AND LOWS WITH HIGHS IN THE LOW TO MID 90S AND LOWS GENERALLY IN THE MID 70S. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... PRIMARILY VFR AT BOTH TERMINALS WITH THE EXCEPTION OF EARLY MVFR CIGS AND THUNDERSTORMS. THUNDERSTORM INITIATION TIMING IS SIMILAR TO YESTERDAY...BUT MODELS ARE SHOWING THE THUNDERSTORM ACTIVITY DIMINISHING RATHER QUICKLY...AROUND 00Z. LOW LEVEL MOISTURE HAS STUCK AROUND LONGER THAN EXPECTED...BUT SATELLITE HAS SHOWN A DRYING TREND TO THE WEST AND THAT SHOULD CONTINUE IN THE AFTERNOON AS TEMPERATURES RISE. EXTENDED AVIATION OUTLOOK...PRIMARILY VFR EXCEPT FOR SHORT-LIVED RESTRICTIONS POSSIBLE IN MAINLY AFTERNOON/EVENING SHOWERS AND THUNDERSTORMS. && .MARINE... SIMILAR TO PAST DAYS IN SOME COASTAL AREAS...CONVECTION MAY POSE A THREAT FOR DANGEROUS LIGHTNING AND LOCALIZED CONVECTIVE WIND GUSTS. IT APPEARS THAT SHOWERS AND TSTMS WILL BE EVENTUALLY BECOME MORE NUMEROUS TODAY. OTHER THAN TSTM HAZARDS...LITTLE TO NO CHANGE TO THE COASTAL WATERS FORECAST PHILOSOPHY THROUGH TONIGHT. SW FLOW 15 KT OR LESS AND SEAS 2-4 FT. ATLANTIC HIGH PRESSURE WILL PREVAIL AS A TROUGH OF LOW PRESSURE LINGERS JUST INLAND THROUGH THE MIDDLE OF NEXT WEEK. A SOUTH TO SOUTHWEST FLOW WILL PERSIST WITH WINDS REACHING 15 TO 20 KNOTS DURING NOCTURNAL SURGING. SEAS WILL ALSO INCREASE IN CONJUNCTION WITH INCREASING WINDS...BUT EXPECT CONDITIONS TO GENERALLY REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA THROUGH THE FORECAST PERIOD. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...NONE. MARINE...NONE. && SYNOPSIS... NEAR TERM...JRL SHORT TERM...JHP LONG TERM...JHP AVIATION...BDC MARINE...JHP
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE CHARLESTON SC 1105 AM EDT MON JUL 30 2012 AMZ330-350-352-354-374-GAZ087-088-099>101-114>119-137>141-SCZ040- 042>045-047>052-311515- CHARLESTON HARBOR- WATERS FROM SOUTH SANTEE RIVER TO EDISTO BEACH SC OUT 20 NM- 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-DORCHESTER-INLAND BERKELEY- INLAND JASPER-BEAUFORT-COASTAL COLLETON-CHARLESTON-COASTAL JASPER- TIDAL BERKELEY- 1105 AM EDT MON JUL 30 2012 ...ISOLATED SEVERE THUNDERSTORMS AND LOCALIZED FLOODING POSSIBLE THIS AFTERNOON AND EVENING... THIS HAZARDOUS WEATHER OUTLOOK IS FOR ATLANTIC COASTAL WATERS...SOUTHEAST GEORGIA AND SOUTHEAST SOUTH CAROLINA. .DAY ONE...TODAY AND TONIGHT. SEVERE THUNDERSTORMS...SCATTERED TO NUMEROUS THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS SOUTHEAST GEORGIA AND SOUTHERN SOUTH CAROLINA TODAY AND CONTINUE INTO THE EARLY EVENING HOURS. A FEW OF THE STORMS COULD BECOME SEVERE WITH THE MAIN THREAT BEING DAMAGING WIND GUSTS AND DEADLY CLOUD TO GROUND LIGHTNING. ALSO...TORRENTIAL RAINFALL COULD BE A CONCERN WITH ANY SHOWERS AND STORMS THAT DEVELOP AND SOME LOCALIZED FLOODING IS POSSIBLE. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY. THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .SPOTTER INFORMATION STATEMENT... PLEASE RELAY ANY REPORTS OF HAZARDOUS WEATHER INCLUDING...BUT NOT LIMITED TO LARGE HAIL...DAMAGING WINDS...AND FLOODING TO THE NATIONAL WEATHER SERVICE IN CHARLESTON AT 1-888-383-2024.
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHARLESTON SC
248 PM EDT MON JUL 30 2012
GAZ116-117-119-138-139-301915-
COASTAL BRYAN-COASTAL CHATHAM-COASTAL LIBERTY-INLAND BRYAN-INLAND
LIBERTY-
248 PM EDT MON JUL 30 2012
...STRONG THUNDERSTORMS WILL IMPACT PORTIONS OF LIBERTY...BRYAN AND
CHATHAM COUNTIES THROUGH 315 PM EDT...
AT 248 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM...NEAR SUNBURY...MOVING EAST AT 15 MPH.
SOME LOCATIONS THAT WILL BE AFFECTED INCLUDE...
BELFAST...HALFMOON LANDING...KELLER...RETREAT...ST. CATHERINES ISLAND
AND SUNBURY...
PREPARE NOW FOR THE FOLLOWING HAZARDS...
STRONG WINDS OF 45 TO 55 MPH...
PRECAUTIONARY/PREPAREDNESS ACTIONS...
HAVE AN ACTION PLAN READY IN THE EVENT THIS STORM STRENGTHENS OR A
WARNING IS ISSUED. CONTINUE TO MONITOR NOAA WEATHER RADIO ALL HAZARDS
FOR THE LATEST WEATHER INFORMATION.
BE ALERT FOR RAPIDLY CHANGING WEATHER CONDITIONS AS STORMS APPROACH.
BE READY TO TAKE IMMEDIATE ACTION IN CASE A SEVERE THUNDERSTORM
WARNING IS ISSUED FOR YOUR LOCATION.
&&
LAT...LON 3169 8144 3187 8130 3184 8102 3183 8103
3181 8103 3176 8107 3172 8113 3163 8112
3162 8113
TIME...MOT...LOC 1849Z 277DEG 11KT 3174 8125The Charleston,SC radar (KCLX), 105 km away, was scanning. The volume nearest the first event began at 19:06 UTC.
3 thunderstorm wind, 1 hail. Local standard time, as filed.
Trained spotter e-mailed report of several large limbs snapped off.
Tree down on Griffin Lake Road at George Hurst Road.
One tree was reported down on Old River Road near Stonegate Drive.
Public reported nickel size hail.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Georgia in 2012Every state in 2012This day in weather historyWarnings in Georgia, July 2012
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: 402352, 402350, 402354, 402349.