Scattered thunderstorms affected the Upstate ahead of a strong cold front. One of the thunderstorms developed a small bow echo on radar.
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 GSP wrote it up.
Scattered thunderstorms affected the Upstate ahead of a strong cold front. One of the thunderstorms developed a small bow echo on radar. Wind damage was reported in association with the feature.
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 Greenville-Spartanburg, SC wrote its last area forecast discussion before the first event at Sep 18, 1:25 PM EST, 21 minutes earlier.
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
225 PM EDT TUE SEP 18 2012
.SYNOPSIS...
A COLD FRONT WILL SLOWLY CROSS OUR REGION FROM THE WEST REACHING THE
COAST BY WEDNESDAY MORNING. DRIER HIGH PRESSURE THEN BUILDS IN FROM
THE OHIO RIVER VALLEY AND WILL REMAIN OVER THE AREA THROUGH MID
WEEK. EXPECT THE NEXT COLD FRONT TO CROSS OUR AREA DURING THE
WEEKEND.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
CONVECTION ALONG THE NRN END OF PRE-FRONTAL MOISTURE BOUNDARY IS
WEAKENING AS IT MOVES INTO THE PIEDMONT WHICH WAS WORKED OVER BY THE
EARLIER STRONG STORMS. THE SRN END OF THE LINE IS MAINTAINING ITS
STRENGTH AS IT MOVES INTO AN AREA NOT AS WORKED OVER. THIS SEGMENT
IS ALSO WHERE A TRIPLE POINT LOW ALONG THE LINE WILL HELP WITH KEEP
LOW LEVEL CONVERGENCE HIGH. EVEN WITH WEAKENING ACROSS THE NORTH...
WIDESPREAD SHOWERS WILL MOVE ACROSS THE AREA THRU THE AFTERNOON AS
COVERAGE REMAINS HIGH. A SVR STORM OR TWO IS STILL POSSIBLE ACROSS
THE UPSTATE AND NE GA WHERE INSTABILITY IS HIGHER AND SHEAR REMAINS
STRONG. SVR POTENTIAL WILL DECREASE BEHIND THE LINE OF STORMS...BUT
SHRA WILL LINGER AS THE POLAR FRONT MOVES INTO THE AREA. WILL KEEP
THE FFA IN PLACE THRU EXPIRATION AS PRECIP SLOWLY TAPERS OFF AND
SOME FLOODING CONTINUES. THIS FRONT WILL MOVE EAST DURING THE
EVENING ENDING THE PRECIP THREAT. GUSTY WINDS WILL CONTINUE AHEAD OF
THE FIRST BOUNDARY WITH WIND SHIFTING SLIGHTLY BEHIND AND SPEEDS
SLOWLY DIMINISHING. WINDS WILL SHIFT TO THE NORTH BEHIND THE POLAR
FRONT BUT REMAIN ABOVE CALM. THERE COULD BE SOME BRIEF FOG THIS
EVENING AS WINDS DIMINISH AND LOW LEVEL MOISTURE LINGER.
HOWEVER...EXPECT ANY FOG OUTSIDE OF THE MTNS TO BE SHORT LIVED AS
DRIER AIR MOVES IN AND WINDS KEEP THE ATMOS SLIGHTLY MIXED. CANNOT
RULE OUT SOME DENSE MTN VALLEY FOG OVERNIGHT...BUT WINDS AND
LINGERING CLOUDS SHUD KEEP IT IN THE PATCHY RANGE. LOWS WILL
ACTUALLY BE NEAR TO SLIGHTLY ABOVE NORMAL AS CLOUDS AND WINDS KEEP
ATMOS MIXED AND WARM.
HIGH PRESSURE BEGINS TO BUILD INTO THE AREA WED...BUT THE CENTER OF
THE HIGH REMAINS TO OUR NORTH KEEPING A DECENT PRESSURE GRADIENT
ACROSS THE AREA THRU MUCH OF THE DAY. WITH BREEZY WINDS JUST ABOVE
THE SURFACE WED MORN...EXPECT GUSTY CONDITIONS TO DEVELOP AS MIXING
BEGINS BY MID MORNING. THE GUSTS WILL LINGER THRU THE EARLY
AFTERNOON BEFORE DIMINISHING LATE IN THE DAY. CLOUDS MAY SCATTER OUT
BRIEFLY WED MORN...BUT SHUD RETURN ACROSS MUCH OF THE AREA BY
AFTERNOON AS HEATING ACTS ON LINGERING LOW LEVEL MOISTURE. EXPECT
THE DRY FCST TO CONTINUE. HIGHS WILL BE 5 TO 10 DEGREES BELOW NORMAL.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
AS OF 145 PM TUESDAY...THE SHORT TERM LOOKS TO BE QUIET...AS DRY
HIGH PRES LINGERS ALONG THE EAST COAST AHEAD OF ANOTHER COLD FRONT
THAT WILL DROP SOUTH OUT OF CANADA INTO THE UPPER MIDWEST. FCST
SNDGS LOOK STABLE FOR THURSDAY. ON FRIDAY...THE NAM HAS A FINGER OF
LLVL ATLANTIC MOISTURE ROUND THE BACKSIDE OF THE HIGH PRES SYSTEM
INTO THE SOUTHERN APPALACHIANS RESULTING IN CAPES OVER 1000 J/KG IN
THE MTNS. WILL KEEP THE FCST DRY FOR NOW. TEMPS ARE EXPECTED TO
SLOWLY TREND BACK TO NEAR NORMAL BY FRIDAY...AS HEIGHTS RISE ALOFT
AND THE AIR MASS IN PLACE MODERATES.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF NOON TUESDAY...THE MAIN WEATHER FEATURE IN THE EXTENDED IS
ANOTHER STRONG COLD FROPA THIS WEEKEND. THE MODELS HAVE TRENDED A
LITTLE SLOWER WITH THE TIMING OF THE FRONT...BUT STILL EXPECTING IT
TO CROSS THE AREA LATE SATURDAY AND BE THRU THE AREA BY SUNDAY
MORNING. THE GULF WILL BE CLOSED FOR BUSINESS WITH THIS FRONT...SO
ONLY A CHC POP FOR THE MTNS WITH THE FRONT AND SLGT CHC ELSEWHERE
SATURDAY INTO SATURDAY NIGHT.
CANADIAN HIGH PRES WILL BUILD IN ACRS THE REGION BEHIND THE FRONT
SUNDAY INTO MONDAY AND SETTLE ALONG THE EAST COAST ON TUESDAY. THE
CWFA WILL EXPERIENCE FALL-LIKE CONDITIONS WITH TEMPS ABOUT 5-10
DEGREES BELOW NORMAL ON MONDAY...THEN BOUNCE BACK A CATEGORY OR SO
ON TUESDAY.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
AT KCLT AND ELSEWHERE...LINE OF CONVECTION DEVELOPING ON PRE-FRONTAL
MOISTURE BOUNDARY WILL SPREAD SLOWLY EAST ACROSS THE AREA THRU THE
REST OF THE AFTERNOON. HAVE TEMPO TS AND MVFR CONDITIONS FOR THE
CONVECTION...XCPT TEMPO IFR KAVL WHERE CONDITIONS ARE WORSE. AFTER
THIS LINE MOVES THRU...SHRA WILL LINGER AHEAD OF THE MAIN FRONTAL
BOUNDARY UNTIL EARLY EVENING WHEN THAT FRONT MOVES THRU. THERE WILL
BE A SMALL WIND SHIFT FROM SSW TO WSW WITH THE FIRST FRONT...THEN TO
N TO NW BEHIND THE SECOND. THERE WILL BE SOME LOW END GUSTS THIS
AFTERNOON...THEN STEADY ABOVE CALM SPEEDS OVERNIGHT. MVFR CIGS WILL
LINGER UNTIL THE SECOND FRONT PASSES THRU. COULD BE SOME BRIEF MVFR
FOG UNTIL DRIER AIR WORKS IN BEHIND THE SECOND FRONT. HOWEVER...DO
NOT EXPECT ANY SIGNIFICANT VSBY RESTRICTIONS EXCEPT IN THE MTN
VALLEYS AS AIR SHUD REMAIN MIXED EVEN IF THE DRIER AIR IS SLOWER TO
MOVE IN. CIGS SHUD BECOME LOW VFR OR EVEN SCATTER OUT BEHIND THE
SECOND FRONT. EXPECT LOW VFR CLOUDS TO RETURN OR CONTINUE WED
MORNING HEATING ACTS ON THE LINGERING LOW LEVEL MOISTURE OVER THE
AREA. GUSTY NELY WINDS WILL DEVELOP WITH MIXING BY MID MORNING AND
CONTINUE THRU AT LEAST EARLY AFTERNOON.
OUTLOOK...HIGH PRESSURE WILL BUILD OVER THE REGION FOR THE END OF
THE WEEK PRODUCING VFR CONDITIONS.
AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE
PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE
CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)...
WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR GAZ010-017.
NC...FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR NCZ033-048>053-058-
059-062>065-501-503-505-507-509.
SC...FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR SCZ001>003.
&&
SYNOPSIS...PAT
NEAR TERM...RWH
SHORT TERM...ARK
LONG TERM...ARK
AVIATION...RWHHAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC 308 AM EDT TUE SEP 18 2012 GAZ010-017-NCZ033-048>053-058-059-062>065-501-503-505-507-509- SCZ001>003-190715- RABUN-HABERSHAM-AVERY-MADISON-YANCEY-MITCHELL-SWAIN-HAYWOOD-BUNCOMBE- GRAHAM-NORTHERN JACKSON-MACON-SOUTHERN JACKSON-TRANSYLVANIA- HENDERSON-CALDWELL MOUNTAINS-BURKE MOUNTAINS-MCDOWELL MOUNTAINS- RUTHERFORD MOUNTAINS-POLK MOUNTAINS-OCONEE MOUNTAINS- PICKENS MOUNTAINS-GREENVILLE MOUNTAINS- 308 AM EDT TUE SEP 18 2012 ...FLOOD WATCH IN EFFECT UNTIL NOON EDT TODAY... THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEAST GEORGIA...WESTERN NORTH CAROLINA AND UPSTATE SOUTH CAROLINA. .DAY ONE...TODAY AND TONIGHT. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. FLOOD WATCH. THE THREAT FOR LOCALLY HEAVY SHOWERS AND EMBEDDED THUNDERSTORMS WILL CONTINUE TODAY. THERE IS ALSO THE POSSIBILITY THAT THUNDERSTORMS WILL BE STRONG ENOUGH TO PRODUCING LOCALIZED DAMAGING WIND GUSTS. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY. NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SKYWARN SPOTTERS ARE REQUESTED TO FORWARD ANY REPORTS OF DAMAGING WINDS OR FLASH FLOODING TO OUR OFFICE. GAZ018-026-028-029-NCZ035>037-056-057-068>072-082-502-504-506-508- 510-SCZ004>014-019-190715- STEPHENS-FRANKLIN-HART-ELBERT-ALEXANDER-IREDELL-DAVIE-CATAWBA-ROWAN- CLEVELAND-LINCOLN-GASTON-MECKLENBURG-CABARRUS-UNION NC- GREATER CALDWELL-GREATER BURKE-EASTERN MCDOWELL-GREATER RUTHERFORD- EASTERN POLK-GREATER OCONEE-GREATER PICKENS-GREATER GREENVILLE- SPARTANBURG-CHEROKEE-YORK-ANDERSON-ABBEVILLE-LAURENS-UNION SC- CHESTER-GREENWOOD- 308 AM EDT TUE SEP 18 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEAST GEORGIA...PIEDMONT NORTH CAROLINA...WESTERN NORTH CAROLINA AND UPSTATE SOUTH CAROLINA. .DAY ONE...TODAY AND TONIGHT. THE THREAT OF LOCALLY HEAVY RAIN WILL CONTINUE TODAY AND THUNDERSTORMS ARE ALSO EXPECTED TO REDEVELOP. LOCALLY STRONG TO SEVERE STORMS MAY BE SEEN AS WELL...PRODUCING HAIL OR DAMAGING WIND GUSTS...AND PERHAPS EVEN A BRIEF TORNADO. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY. NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SKYWARN SPOTTERS ARE REQUESTED TO FORWARD ANY REPORTS OF HAIL...DAMAGING WINDS...TORNADOES OR FLASH FLOODING TO OUR OFFICE.
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1201 PM EDT TUE SEP 18 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1140 AM FLASH FLOOD JONAS RIDGE 35.97N 81.89W
09/18/2012 BURKE NC BROADCAST MEDIA
FLOODING OF HIGHWAY NC 183. ROADWAY COVERED FROM FLOODED
CREEK.
&&
HGSPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1240 PM EDT TUE SEP 18 2012
NCZ071-082-SCZ009-181730-
MECKLENBURG-UNION-YORK-
1240 PM EDT TUE SEP 18 2012
...STRONG THUNDERSTORMS WILL AFFECT EASTERN YORK...MECKLENBURG AND
UNION COUNTIES THROUGH 130 PM EDT...
AT 1240 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM 5 MILES NORTHWEST OF
LAKE WYLIE TO FORT MILL TO CATAWBA...MOVING NORTHEAST AT 45 MPH.
THESE STORMS WILL IMPACT LOCATIONS NEAR...
PAW CREEK...
I-77 AT I-85...
MINT HILL...
UNC CHARLOTTE...
UNIONVILLE...
MARSHVILLE...
PEA SIZE HAIL...WIND GUSTS UP TO 40 MPH...AND TORRENTIAL RAIN ARE
EXPECTED WITH THESE STORMS.
LAT...LON 3483 8031 3481 8043 3481 8079 3494 8079
3505 8089 3484 8086 3482 8089 3482 8097
3515 8118 3515 8101 3530 8101 3540 8076
3535 8069 3527 8066 3517 8046 3495 8030
HGSPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1241 PM EDT TUE SEP 18 2012
NCZ036-037-056-057-181745-
CATAWBA-DAVIE-IREDELL-ROWAN-
1241 PM EDT TUE SEP 18 2012
...STRONG THUNDERSTORMS WILL AFFECT DAVIE...EASTERN CATAWBA...IREDELL
AND NORTHERN ROWAN COUNTIES THROUGH 145 PM EDT...
AT 1239 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM COURTNEY TO
CATAWBA...MOVING EAST AT 35 MPH.
THESE STORMS WILL IMPACT LOCATIONS NEAR...
STATESVILLE...
FARMINGTON...
TROUTMAN...
BERMUDA RUN...
ADVANCE...
COOLEEMEE...
WIND GUSTS OF 40 TO 50 MPH...AND TORRENTIAL RAIN ARE EXPECTED WITH
THESE STORMS.
HEAVY RAINS MAY FLOOD AREAS WITH POOR DRAINAGE...SUCH AS DITCHES AND
UNDERPASSES. AVOID THESE AREAS AND DO NOT CROSS FLOODED ROADS. WATER
LEVELS OF SMALL STREAMS AND RIVERS MAY ALSO RISE RAPIDLY. SEEK HIGHER
GROUND IF THREATENED BY FLOOD WATERS.
LAT...LON 3561 8130 3606 8069 3605 8049 3607 8046
3601 8041 3599 8041 3596 8037 3589 8036
3588 8041 3585 8038 3582 8046 3579 8047
3574 8045 3571 8032 3568 8033 3563 8029
JOHSPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC 1245 PM EDT TUE SEP 18 2012 NCZ036-056-057-068>072-508-181745- CABARRUS-CATAWBA-CLEVELAND-GASTON-GREATER RUTHERFORD-IREDELL-LINCOLN-MECKLENBURG-ROWAN- 1245 PM EDT TUE SEP 18 2012 ...STRONG THUNDERSTORMS WILL AFFECT CLEVELAND...GASTON...LINCOLN... NORTHWESTERN CABARRUS...NORTHWESTERN MECKLENBURG...SOUTHEASTERN IREDELL...SOUTHEASTERN RUTHERFORD...SOUTHERN CATAWBA AND SOUTHERN ROWAN COUNTIES THROUGH 145 PM EDT... AT 1244 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM 6 MILES NORTHEAST OF VALE TO CLIFFSIDE...MOVING EAST AT 35 MPH. THESE STORMS WILL IMPACT LOCATIONS NEAR... MAIDEN... SHELBY... LINCOLNTON... TERRELL... IRON STATION... LAKE NORMAN... WIND GUSTS OF 40 TO 50 MPH...AND TORRENTIAL RAIN ARE EXPECTED WITH THESE STORMS. HEAVY RAINS MAY FLOOD AREAS WITH POOR DRAINAGE...SUCH AS DITCHES AND UNDERPASSES. AVOID THESE AREAS AND DO NOT CROSS FLOODED ROADS. WATER LEVELS OF SMALL STREAMS AND RIVERS MAY ALSO RISE RAPIDLY. SEEK HIGHER GROUND IF THREATENED BY FLOOD WATERS. LAT...LON 3564 8036 3516 8103 3519 8194 3561 8135 JOH
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
147 PM EDT TUE SEP 18 2012
GAZ018-026-028-SCZ001-004-010-181815-
ANDERSON-FRANKLIN-GREATER OCONEE-HART-OCONEE MOUNTAINS-STEPHENS-
147 PM EDT TUE SEP 18 2012
...STRONG THUNDERSTORMS WILL AFFECT FRANKLIN...HART...SOUTHERN
OCONEE...STEPHENS AND WESTERN ANDERSON COUNTIES THROUGH 215 PM EDT...
AT 147 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM OAKWAY TO 5 MILES
SOUTH OF EASTANOLEE TO COMMERCE...MOVING NORTHEAST AT 40 MPH.
THESE STORMS WILL IMPACT LOCATIONS NEAR...
MARTIN...
SENECA...
LAKE HARTWELL...
LAKE KEOWEE...
ROYSTON...
LAVONIA...
PEA SIZE HAIL...WIND GUSTS UP TO 40 MPH...AND TORRENTIAL RAIN ARE
EXPECTED WITH THESE STORMS. LOW LYING AND POOR DRAINAGE AREAS MAY
EXPERIENCE FLOODING.
LAT...LON 3426 8334 3432 8340 3442 8339 3446 8340
3448 8346 3466 8336 3486 8291 3479 8288
3474 8290 3473 8286 3467 8285 3464 8281
3444 8272 3430 8294 3425 8311 3426 8313
3423 8317 3426 8331 3422 8335
HGSPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
215 PM EDT TUE SEP 18 2012
GAZ028-SCZ004-005-010-181845-
ANDERSON-GREATER OCONEE-GREATER PICKENS-HART-
215 PM EDT TUE SEP 18 2012
...STRONG THUNDERSTORMS WILL AFFECT HART...SOUTHEASTERN OCONEE...
SOUTHWESTERN PICKENS AND WESTERN ANDERSON COUNTIES THROUGH 245 PM
EDT...
AT 215 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM OAKWAY TO 3 MILES
EAST OF WHITWORTH TO ROYSTON...MOVING EAST AT 40 MPH.
THESE STORMS WILL IMPACT LOCATIONS NEAR...
SENECA...
CLEMSON...
CENTRAL...
ANDERSON...
PEA SIZE HAIL...WIND GUSTS UP TO 40 MPH...AND TORRENTIAL RAIN ARE
EXPECTED WITH THESE STORMS. THE HEAVY RAINFALL MAY FLOOD LOW LYING
AND POOR DRAINAGE AREAS. IN ADDITION...THE GUSTY WINDS COULD TOPPLE
A FEW TREES IN AREAS WITH VERY WET SOIL.
LAT...LON 3427 8312 3428 8310 3441 8310 3450 8305
3451 8308 3453 8308 3456 8313 3462 8314
3471 8303 3487 8266 3464 8256 3437 8264
3423 8309
HGThe Greer radar (KGSP), 64 km away, was scanning. The volume nearest the first event began at 18:44 UTC.
1 thunderstorm wind. Local standard time, as filed.
Trees were blown down from New Hope Rd, 5.5 miles west of Anderson, to Gerrard Rd 4.5 miles west northwest of town.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in South Carolina in 2012Every state in 2012This day in weather historyWarnings in South Carolina, September 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: 414240.