Easterly upslope flow behind a cold front helped to initiate thunderstorms over the North Carolina foothills during the afternoon hours. With mid-level winds of about 35 knots and plenty of moisture pooled behind the front, the storms produced quite a bit of severe weather as they moved across the foothills and piedmont.
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.
Easterly upslope flow behind a cold front helped to initiate thunderstorms over the North Carolina foothills during the afternoon hours. With mid-level winds of about 35 knots and plenty of moisture pooled behind the front, the storms produced quite a bit of severe weather as they moved across the foothills and piedmont.
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 Aug 11, 12:46 PM EST, 4 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC 146 PM EDT THU AUG 11 2011 .SYNOPSIS... HIGH PRESSURE WILL MOVE FROM THE OHIO VALLEY TODAY TO THE EAST COAST ON FRIDAY. INCREASINGLY MOIST SOUTHERLY FLOW WILL BE SEEN ON SATURDAY AHEAD OF AN APPROACHING COLD FRONT WHOSE PASSAGE IS SLATED FOR SUNDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1045 AM THURSDAY...PREVIOUS CLOUD DECK HAS CLEARED OUT AS SHORT WAVE MOVES EAST OF THE AREA. HOWEVER...CLOUDS EXPECTED TO FILL BACK IN AS CONVECTIVE CU DEVELOPS AND DEBRIS FROM THE MCS OVER AL MOVES EASTWARD. WARM START AND EARLY SUN SHOULD HELP US REACH FCST HIGHS...WHICH ARE SLIGHTLY COOLER ACROSS THE NORTH IN LINE WITH OBS THICKNESSES AND H85 COLD FRONT MOVING INTO THE AREA. POP TRENDS LOOK GOOD AS WELL AS LATEST GUIDANCE SUGGESTS CONVECTION INITIATING OVER THE MTNS AND MOVING INTO THE FOOTHILLS/PIEDMONT THIS AFTERNOON. BASICALLY LITTLE CHANGE IN FCST EXCEPT TO UPDATE CURRENT CONDITIONS. PREVIOUS DISCUSSION. A BROAD LONG WAVE TROUGH WILL REMAIN OVER THE ERN STATES THROUGH TONIGHT. IT/S DEBATABLE WHERE THE SFC FEATURES ARE OVER THE REGION RIGHT NOW. HPC IS ANALYZING A SFC FRONT OVER ERN NC...THE SC MIDLANDS AND CENTRAL GA. THIS IS WHERE I/VE GOT IT AS WELL SINCE THERE IS A WEAK WIND SHIFT A ABOUT A 10 DEGREE DEWPOINT GRADIENT ACROSS THE FRONT. HOWEVER...GSP GOT UP TO 99 DEGREES YESTERDAY...NOT EXACTLY A TYPICAL POST FROPA TEMPERATURE. I/M GOING TO STICK WITH CALLING IT A /COLD/ FRONT. THERE IS A SECOND /COLD/ FRONT WHICH HAS MORE OF A TEMPERATURE CONTRAST ALONG IT WHICH HAS HUNG UP OVER ERN TN. DEWPOINTS HAVE POOLED A BIT ALONG THIS FEATURE...THOUGH MODEL SOUNDINGS AND MOS NUMBERS SUPPORT DEWPOINTS STAYING NEAR 60...OVER THE FA TODAY. THE GFS 1000-850 MB THICKNESSES REMAIN HIGH OVER THE SW PART OF THE FA...WITH 1443M 100-850 MB THICKNESS CENTERED DOWN OVER ELBERT CO BY 00 UTC THIS EVENING. IN SHORT...IT SHOULD BE DRY AND HOT AGAIN...ESPECIALLY ONCE A SOLID AC DECK CLEARS THE AREA. THIS SHOULD HAPPEN A LITTLE AFTER 12 UTC AS AN ADVECTIVE SHORT WAVE MOVES E OF THE FA. THE NAM IS FARTHER SOUTH WITH IT/S THICKNESS RIDGE...WHICH GIVES IT/S LLVL WIND FIELD MORE OF A NE ORIENTATION...VS THE GFS WHICH HAS S WINDS OVER THE ERN PART OF THE FA...AND NW ALONG THE TN LINE. THE SREF SUPPORTS THE GFS...AS DO THE MAX TEMPS FROM YDAY. AND THAT/S WHAT I/M GOING WITH. THE UPSHOT OF THIS IS CONVERGENCE SHOULD BE SUFFICIENT ACROSS THE MTNS FOR SHRA TO DEVELOP THIS AFTN. THE SHRA SHOULD SLOWLY PROGRESS TO THE E DURING THE EVENING...INTO THE CONVERGENCE AXIS OUT ACROSS THE FOOTHILLS. HOWEVER...THE INSTABILITY IS QUITE WEAK. I THINK THAT SPC/S 5 PERCENT SEVERE RISK OVER THE FA IS TOO HIGH...AS IS HPC/S SMALL AREA OF .25 INCH BASIN AVERAGE QPF OVER THE MTNS. I WON/T FEATURE ANY SEVERE WORDING IN THE HWO TDA...AND MY QPF WILL BE LOWER. CHANCE POPS WILL BE CARRIED THIS AFTERNOON...THROUGH LATE EVENING...BUT THEY WILL BE LOW CHANCE POPS. AND I/LL STAY CLOSER TO THE WARMER MAV NUMBERS ACROSS THE FA TODAY. && .SHORT TERM /FRIDAY THROUGH SATURDAY/... AS OF 230 AM THURSDAY...STILL EXPECTING JUST SUBTLE VORT ENERGY TO RIPPLE THRU THE NON-DESCRIPT WNW FLOW ALOFT ON FRIDAY. AT THE SFC... WEAK HIPRES REMAINS PROGGED TO SHIFT OFFSHORE EFFECTIVELY VEERING LLVL FLOW TO AN EASTERLY DIRECTION ATOP THE CWFA. WITH JUST NOMINAL MOISTURE FLUX AND BLYR DWPT INCREASES...THE ATMOSPHERE SHOULD REMAIN WEAKLY UNSTABLE. WEAK FORCING REGIME SHOULD KEEP DEEP CONVECTIVE CVRG ISOLATED BUT SLIGHT CHANCES LINGERING INTO FRIDAY NIGHT AS WEAK WAA/UPSLOPE FLOW CONTINUES TO DEVELOP AND LLVL MOISTURE FLUX STEADILY INCREASES. AS S/WV ENERGY DIVES TOWARD THE OHIO VALLEY ON SATURDAY...MID/UPPER LVL FLOW ATOP THE CWFA WILL BECOME BROADLY DIFFLUENT...AND WELL AHEAD OF LLVL FRONTAL ZONE WAA FLOW WILL ALSO STEADILY INCREASE. MODEL PWAT VALUES INCREASE TO ABV CLIMO...AND IN COMBINATION WITH THE ABOVE FORCING MECHANISMS...SHOULD LEAD TO SCATTERED TO NUMEROUS DIURNALLY ENHANCED SHOWERS AND TSTMS. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AS OF 325 AM THURSDAY...ALTHOUGH THE RESPONSE AMONG THE 00 UTC OP AND ENS MODELS WITH RESPECT TO THE INCREASING FORCING...DEEP MOISTURE AND FRONTAL ZONE PASSAGE SATURDAY NIGHT INTO SUNDAY IS VARIABLE... VIRTUALLY EVERY SOLUTION HAS SOME DEGREE OF MODERATE RESPONSE... ESPECIALLY WHERE TERRAIN LIFT IS MAXIMIZED. HARD TO BELIEVE THAT THERE WILL NOT BE AT LEAST NUMEROUS DEEP CONVECTIVE CVRG...WITH PERHAPS LOCALLY HEAVY RAIN. BOTH THE 00 UTC OP GFS AND ECMWF TIME DRY SLOT THRU THE CWFA SUNDAY NIGHT LEAVING JUST A TOKEN WRAP-AROUND SHOWER THREAT ACRS MY NORTHERN TIER OF CNTYS INTO MONDAY...OTHERWISE A DRY POST-FRONT AIRMASS IS STILL PROGGED TO SETTLE OVER THE REGION TO START THE WORKWEEK. EASTERN CONUS L/WV TROUGH AXIS WILL SLOWLY PROGRESS EASTWARD THRU TUESDAY AND WEDNESDAY...AND SAVE FOR THE SMALL POTENTIAL FOR A FEW DIURNAL MTN SHOWERS EACH DAY...EFFECTIVELY DRY NW FLOW WILL BE SEEN. && .AVIATION /18Z THURSDAY THROUGH TUESDAY/... AT KCLT AND ELSEWHERE...LINE OF TSRA FORMING ALONG THE BLUE RIDGE WILL SPREAD EAST AND SOUTH THRU THE AFTERNOON. HAVE INCLUDED CB EVERY SITE WITH TEMPO TS AT KHKY WHERE TSRA IS NEARBY. WILL AMD OTHER STIES AS NEEDED. OTHERWISE...EXPECT VFR CIGS TO DEVELOP THIS AFTERNOON AND CONTINUE OVERNIGHT AS SELY FLOW ACTS ON LINGERING LOW LEVEL MOISTURE. EVEN THE MORE BULLISH NAM KEEPS CIGS AT TAF SITES VFR...SO HAVE GONE THAT WAY AS WELL. BEST CHC FOR ANY FOG IS AT KAVL. DID NOT MENTION ANY SHRA BUT THEY COULD LINGER OVERNIGHT AT THE NC SITES AS WELL. EXPECT AN EVEN BETTER DAY FOR CONVECTION FRI BUT TOO EARLY TO INCLUDE IN TAFS ATTM. KEPT VFR CIGS THRU THE PERIOD. WINDS ARE TRICKY WITH WEAK LOW PRESSURE AND LEE TROF IN PLACE. HAVE TRENDED TOWARD A MDL BLEND WITH E TO SE WIND BECOMING NE OVERNIGHT. KAVL THE EXCEPTION WHERE N WIND CONTINUES. OUTLOOK...EVEN BETTER CONVECTION CHANCES SATURDAY AND SUNDAY. A COLD FRONT SHOULD BRING MUCH DRIER WEATHER MON AND TUE. 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...NONE. NC...NONE. SC...NONE. && SYNOPSIS...CSH NEAR TERM...MCAVOY/RWH SHORT TERM...CSH LONG TERM...CSH/NED AVIATION...RWH
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC 600 AM EDT THU AUG 11 2011 GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065- 068>072-082-501>510-SCZ001>014-019-121000- RABUN-HABERSHAM-STEPHENS-FRANKLIN-HART-ELBERT-AVERY-ALEXANDER- IREDELL-DAVIE-MADISON-YANCEY-MITCHELL-SWAIN-HAYWOOD-BUNCOMBE-CATAWBA- ROWAN-GRAHAM-NORTHERN JACKSON-MACON-SOUTHERN JACKSON-TRANSYLVANIA- HENDERSON-CLEVELAND-LINCOLN-GASTON-MECKLENBURG-CABARRUS-UNION NC- CALDWELL MOUNTAINS-GREATER CALDWELL-BURKE MOUNTAINS-GREATER BURKE- MCDOWELL MOUNTAINS-EASTERN MCDOWELL-RUTHERFORD MOUNTAINS- GREATER RUTHERFORD-POLK MOUNTAINS-EASTERN POLK-OCONEE MOUNTAINS- PICKENS MOUNTAINS-GREENVILLE MOUNTAINS-GREATER OCONEE- GREATER PICKENS-GREATER GREENVILLE-SPARTANBURG-CHEROKEE-YORK- ANDERSON-ABBEVILLE-LAURENS-UNION SC-CHESTER-GREENWOOD- 600 AM EDT THU AUG 11 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEAST GEORGIA...PIEDMONT NORTH CAROLINA...WESTERN NORTH CAROLINA AND UPSTATE SOUTH CAROLINA. .DAY ONE...TODAY AND TONIGHT. A FEW THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS THE REGION TODAY WITH THE PRIMARY THREAT BEING A FEW CLOUD TO GROUND LIGHTNING STRIKES. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY. A MODERATE COLD FRONT WILL CROSS THE AREA LATER THIS WEEKEND. SCATTERED STRONG THUNDERSTORMS IN ADVANCE OF THIS FRONT WILL BE POSSIBLE SATURDAY AFTERNOON THROUGH SUNDAY. LOCALIZED AREAS OF GUSTY WIND...HAIL AND HEAVY RAIN ARE PROBABLE. .SPOTTER INFORMATION STATEMENT... NONE.
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
102 PM EDT THU AUG 11 2011
NCZ501>504-111745-
BURKE MOUNTAINS-CALDWELL MOUNTAINS-GREATER BURKE-GREATER CALDWELL-
102 PM EDT THU AUG 11 2011
...A STRONG THUNDERSTORM WILL AFFECT NORTHEASTERN BURKE AND SOUTHERN
CALDWELL COUNTIES THROUGH 145 PM EDT...
AT 1258 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 3 MILES WEST OF COLLETTSVILLE...OR 11 MILES WEST
OF LENOIR...MOVING SOUTHEAST AT 15 MPH.
* OTHER LOCATIONS AFFECTED INCLUDE BUT ARE NOT LIMITED TO RUTHERFORD
COLLEGE...LAKE RHODHISS...EDGEMONT...VALDESE...SAWMILLS...LENOIR...
HUDSON...GAMEWELL...CONNELLY SPRINGS...COLLETTSVILLE AND CAJAH'S
MOUNTAIN.
VERY HEAVY RAINFALL...SMALL HAIL...AND WIND GUSTS OF 40 TO 50 MPH
ARE EXPECTED WITH THIS STORM.
FREQUENT LIGHTNING IS OCCURRING WITH THIS STORM. IF OUTDOORS...STAY
AWAY FROM ISOLATED HIGH OBJECTS SUCH AS TREES. MOVE INDOORS IF
POSSIBLE. WHEN INDOORS...STAY AWAY FROM WINDOWS AND DOORS AND AVOID
USING TELEPHONES UNLESS IT IS AN EMERGENCY. TRY TO UNPLUG UNNECESSARY
ELECTRICAL APPLIANCES BEFORE THE THUNDERSTORM APPROACHES.
LAT...LON 3592 8135 3570 8149 3589 8186 3596 8181
3604 8175 3604 8174
07SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
146 PM EDT THU AUG 11 2011
NCZ035-056-502-504-111830-
ALEXANDER-CATAWBA-GREATER BURKE-GREATER CALDWELL-
146 PM EDT THU AUG 11 2011
...A STRONG THUNDERSTORM WILL AFFECT EASTERN BURKE...SOUTHERN
CALDWELL...SOUTHWESTERN ALEXANDER AND WESTERN CATAWBA COUNTIES
THROUGH 230 PM EDT...
AT 142 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR CAJAH'S MOUNTAIN...OR 4 MILES SOUTH OF
LENOIR...MOVING SOUTHEAST AT 10 MPH.
* OTHER LOCATIONS AFFECTED INCLUDE BUT ARE NOT LIMITED TO RUTHERFORD
COLLEGE...LAKE RHODHISS...LAKE HICKORY...VALDESE...SAWMILLS...
RHODHISS...LONGVIEW...LENOIR...ICARD...HUDSON...HILDEBRAN...
HICKORY...GRANITE FALLS...GAMEWELL...CONNELLY SPRINGS...CAJAH'S
MOUNTAIN AND BETHLEHEM.
VERY HEAVY RAINFALL...SMALL HAIL...AND WIND GUSTS OF 40 TO 50 MPH
ARE EXPECTED WITH THIS STORM.
FREQUENT LIGHTNING IS OCCURRING WITH THIS STORM. IF OUTDOORS...STAY
AWAY FROM ISOLATED HIGH OBJECTS SUCH AS TREES. MOVE INDOORS IF
POSSIBLE. WHEN INDOORS...STAY AWAY FROM WINDOWS AND DOORS AND AVOID
USING TELEPHONES UNLESS IT IS AN EMERGENCY. TRY TO UNPLUG UNNECESSARY
ELECTRICAL APPLIANCES BEFORE THE THUNDERSTORM APPROACHES.
LAT...LON 3586 8123 3564 8137 3581 8170 3597 8160
3597 8159
07The Greer radar (KGSP), 129 km away, was scanning. The volume nearest the first event began at 17:50 UTC.
13 thunderstorm wind, 6 hail. Local standard time, as filed.
Quarter size hail fell at the intersection of Connelly Springs Rd and highway 321.
Penny size hail was reported off Horseshoe Bend Rd and in other nearby locations.
Two trees were blown down on highway 10 east of Casar. A tree fell on a house in the area.
A large tree and multiple large limbs were blown down on Davie Academy Rd.
Trees and power lines were blown down on Bethel Church Rd.
Multiple trees and large limbs were blown down in the city of Davidson.
Trees and power lines were blown down along Statesville Rd, with other trees and large limbs down in the area.
Six aircraft were damaged and at least one tree blown down at Concord Regional Airport. Large tree limbs were also blown down near Concord Mills.
Multiple trees were blown down throughout the city of Dallas. Two trees fell on homes. Downed trees also crushed at least two vehicles.
Quarter size hail fell along Hickory Grove Rd.
Quarter size hail fell at the intersection of Hickory Grove Rd and Lees Rd, with hail up to half dollar size reported on the northeast side of Belmont.
Numerous trees, power lines, and utility poles were blown down in the Cramerton and Belmont areas, with multiple trees on homes, including trees on about a dozen mobile homes on Parkdale Dr alone. Two homes were struck by downed trees on Lakewood Rd in Cramerton. Windows were blown out of several buildings in downtown Belmont by wind. At least one person received minor injuries due to broken glass.
Wind stripped the siding off a building on Sam Wilson Rd.
Quarter size hail fell on South Bvd.
Trees were blown down on Old Providence Rd and on Alexander Rd about two miles west of Matthews. Additional trees were blown down to the south and west of town, and an outbuilding was moved off its foundation near the intersection of Abby Walk Lane and McKee Rd.
A few trees were blown down in the Water Oak area.
Trees were blown down on Pleasant Grove Rd.
A tree was blown down onto a house on Johnson St in Monroe.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in North Carolina in 2011Every state in 2011This day in weather historyWarnings in North Carolina, August 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: 341341, 341342, 341343, 341344, 341345, 341346, 341347, 341348, 341349, 341350, 341351, 341357, 341358, 341359, 341364, 341366, 341369, 341372, 341374.