Flash Flood and Hail in North Carolina, August 8, 2012

Name: Flash Flood and Hail in North Carolina, August 8, 2012
Start: 2012-08-08T12:56
End: 2012-08-08T22:00
Location: North Carolina

August 8, 2012 · NWS GSP · 11 events in 8 counties and zones

Where it happened

Every event with a place to put it. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 11

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.

What happened

The episode as NWS GSP wrote it up.

The combination of a dissipating frontal boundary and a hot and humid airmass resulted in numerous showers and thunderstorms over western North Carolina. Some of the thunderstorms caused localized wind damage and large hail. One storm dropped 3.5 inches of rain in a short period of time, causing a small area of flooding east of Charlotte.

What forecasters said that day

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 8, 9:36 AM EST, 3 hours 20 minutes earlier.

Area forecast discussion, Aug 8, 9:36 AM EST, 3 hours 20 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1036 AM EDT WED AUG 8 2012

.SYNOPSIS...
A WEAK STATIONARY FRONT WILL DISSIPATE OVER THE REGION TODAY...BEING
REPLACED BY WEAK HIGH PRESSURE FOR THURSDAY.  A COLD FRONT WILL PUSH
ACROSS THE AREA FROM THE WEST LATE FRIDAY. DRY HIGH PRESSURE WILL
THEN BUILD BEHIND THE FRONT OVER THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM...LOW CLOUDS OVER THE SRN PIEDMONT AND CLT METRO AREA
HAVE BEEN SLOW TO BURN OFF GIVEN THE SATURATED SOIL CONDITIONS
THERE. THESE CLOUDS SHOULD LIFT AND SCATTER BY NOON...WITH PLENTY OF
INSOLATION TO REACH FORECAST AFTN MAX TEMPS. HAVE ACTUALLY BUMPED
MAXES UP A DEGREE IN PLACES WITH NO LOW CLOUDS THIS MORNING.

A WEAK SHORTWAVE WILL CROSS MAINLY THE NRN TIER OF THE FORECAST AREA
LATE TODAY...BUT WEAK LOW LEVEL CONVERGENCE AND DIFFERENTIAL HEATING
WILL PROVIDE THE MAIN TRIGGER FOR SCT AFTN/EVENING CONVECTION.
INSTABILITY WILL BE PLENTIFUL WITH SFC DEWPOINTS IN THE UPPER 60S TO
LOWER 70S AND STEEPER LAPSE RATES ARRIVING ALOFT. MID LEVEL DRY AIR
WILL ALSO CREATE STEEP SFC TO MID LEVEL EQUIVALENT POTENTIAL TEMP
LAPSES TO ENHANCE A DOWNBURST THREAT AND MARGINAL LARGE HAIL THREAT.
COVERAGE MAY BE FAIRLY LIMITED GIVEN THE DRIER AIR ARRIVING
ALOFT...BUT ANY TSTMS MAY BE STRONG WITH A FEW SEVERE.

IN A CHANGE FROM THE PAST FEW NIGHTS...WITH RELATIVELY DRIER AIR IN
PLACE THROUGH A DEEP LAYER...TSTM ACTIVITY SHOULD DIMINISH WITH THE
LOSS OF HEATING THIS EVENING. LESS CLOUDS ARE EXPECTED EARLY IN THE
NIGHT...WHICH SHOULD LEAD TO MORE FOG AND LOW CLOUD DEVELOPMENT LATE.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 AM WEDNESDAY...AN UNSEASONABLY STRONG SHORTWAVE TROF WILL
DIG ACRS THE GREAT LAKES AND OHIO VALLEY ON THURSDAY...WITH HEIGHTS
BEGINNING TO FALL ACRS THE CWFA. FCST SNDGS SHOW LESS INSTBY THAN
WEDNESDAY HOWEVER...WITH WEAK SHEAR. STILL EXPECT DECENT
DESTABILIZATION AND SCATTERED MTN CONVECTION WITH LESS COVERAGE ACRS
THE PIEDMONT. A FEW WET MICROBURSTS CAN BE EXPECTED THU AFTN/EARLY
EVE. HIGH TEMPS NEAR NORMAL.

THURSDAY NIGHT THRU FRIDAY NIGHT...THE SHORTWAVE TROF WILL CONTINUE
TO DIG AND CLOSE OFF INTO AN UPR LOW OVR THE GREAT LAKES. THE ECMWF
SOLN WAS THE MODEL OF CHOICE BY HPC WITH THIS FEATURE...AND HAS A
MODERATELY-FORCED COLD FRONT ENTERING THE MTNS FRI AFTN AND CROSSING
THE PIEDMONT FRI EVE. FCST SNDGS DO NOT LOOK IMPRESSIVE FOR
SEVERE...WITH ONLY 1500-2000 J/KG OF CAPE AND 20-30 KTS OF 0-6KM
BULK SHEAR. THE MAIN CONCERN IS THAT PRE-FRONTAL CLOUDS/PRECIP MAY
LIMIT DESTABILIZATION WITH THE FRONT. HOWEVER...BEING A MORE
SOUTHERN SOLN WITH THE UPR LOW...THE ECMWF BRINGS STRONG DEEP Q
CONVERGENCE WITH THE FRONT AND DECENT UPR JET DIVERGENCE. SO WILL
KEEP MENTION OF SEVERE POTENTIAL IN THE HWO FOR FRI-FRI NGT WITH THE
FRONT. TEMPS NEAR NORMAL FOR LOWS AND A CATEGORY OR TWO BELOW NORMAL.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 330 AM WEDNESDAY...THE FCST WAS LEFT UNCHANGED FROM SATURDAY
ONWARD...AS THE LATEST GUIDANCE DID NOT SIGNIFICANTLY CHANGE FROM
PREVIOUS RUNS. SATURDAY AND SUNDAY STILL LOOK RELATIVELY PLEASANT
FOR EARLY AUGUST...WITH TEMPS A CATEGORY OR SO BELOW NORMAL...AND
BELOW NORMAL HUMIDITY AND POPS.

PREVIOUS DISCUSSION...
AS OF 145 PM TUESDAY...TROUGH AXIS AND COLD FRONT WILL PUSH ACROSS
THE AREA FRIDAY NIGHT INTO EARLY SATURDAY...WITH SOLID CHANCE/LIKELY
POPS LINGERING INTO FRIDAY EVENING. THE GLOBAL MODELS ARE IN DECENT
AGREEMENT IN STALLING THE FRONT SOUTH OF THE CWFA OVER THE
WEEKEND...WITH MUCH DRIER AIR ADVECTING INTO THE AREA. AFTER A
STORMY FRIDAY/FRI NIGHT...THE WEEKEND MAY TURN OUT TO BE QUITE
PLEASANT...WITH TEMPS AVERAGING A LITTLE BELOW NORMAL...AND POPS/
POSSIBLY RH AVERAGING MUCH BELOW NORMAL.

THE MODELS SUGGEST AIR MASS MODIFICATION WILL OCCUR QUICKLY IN THE
WAKE OF THE DEPARTING TROUGH...AS BERMUDA HIGH ALLOWS LOW LEVEL
MOISTURE/INSTABILITY TO RETURN. A MORE TYPICAL SUMMERTIME PATTERN
SHOULD YIELD MORE TYPICAL SUMMERTIME CONDITIONS...WITH ISOLATED TO
WIDELY SCATTERED DIURNAL CONVECTION EXPECTED ON DAYS 6/7. TEMPS WILL
ALSO LIKELY TO CLIMB TO NEAR NORMAL LEVELS BY THIS TIME.

&&

.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
AT KCLT...VISIBLE SATELLITE IMAGERY SHOWS PLENTY OF SCATTERING OF
THE LOW CLOUDS OCCURRING AROUND KCLT LATE THIS MORNING...BUT WITH A
STUBBORN PATCH RIGHT OVER THE AIRFIELD. CIGS SHOULD LIFT TO MVFR
BEFORE 15Z...THEN SCATTER INTO EARLY AFTERNOON. THE BEST COMBINATION
OF LOW LEVEL CONVERGENCE AND INSTABILITY WILL BE FOCUSED TOWARD 21Z
THIS AFTERNOON...SO WILL ADVERTISE TEMPO TSRA FOR INITIAL TRIGGERING
AND SUBSEQUENT OUTFLOWS. SIGNALS REMAIN MIXED ON ANY RESTRICTIONS
LATE TONIGHT...SO WILL CONTINUE TO OMIT FOR NOW.

ELSEWHERE...IFR CIGS ARE VERY SLOWLY LIFTING AND SCATTERING FROM
KGMU TO KAND...WITH KGSP TO KAVL TO KHKY ALREADY VFR. ALL LOCATIONS
SHOULD HAVE ONLY SCT VFR CUMULUS BY 16Z...WITH CUMULUS THEN BUILDING
THIS AFTERNOON WITH HEATING. MTN TSRA SHOULD TRIGGER FIRST...WITH
STEERING FLOW AND OUTFLOWS CARRYING SCATTERED CONVECTION INTO THE
FOOTHILLS...ESPECIALLY IN NC. VCTS STARTING 18Z AT KAVL...AND 19Z AT
THE FOOTHILL SITES...LOOKS WELL TIMED. LIMITED HIGHER CLOUDS
OVERNIGHT MAY LEAD TO MORE WIDESPREAD FOG AND LOW CLOUDS THURSDAY
MORNING.

OUTLOOK...A NORMAL SUMMERTIME DIURNAL TSTM PATTERN IS EXPECTED ON
THURSDAY BEFORE A COLD FRONT WILL APPROACHES FROM THE NW ON FRIDAY
TO INCREASE THUNDERSTORM COVERAGE THROUGH FRI NIGHT. DRIER HIGH PRES
WILL RETURN OVER THE WEEKEND.

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...ARK
NEAR TERM...HG
SHORT TERM...ARK
LONG TERM...ARK/JDL
AVIATION...HG

Hazardous weather outlook, Aug 8, 3:43 AM EST, 9 hours 13 minutes before

HAZARDOUS WEATHER OUTLOOK...CORRECTED
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
443 AM EDT WED AUG 8 2012

GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065-
068>072-082-501>510-SCZ001>014-019-090845-
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-
443 AM EDT WED AUG 8 2012

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEAST GEORGIA...PIEDMONT
NORTH CAROLINA...WESTERN NORTH CAROLINA AND UPSTATE SOUTH CAROLINA.

.DAY ONE...TODAY AND TONIGHT.

SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS THE REGION
THIS AFTERNOON INTO THIS EVENING. A FEW STORMS MAY BE STRONG
ENOUGH TO PRODUCE LOCALLY DAMAGING WIND GUSTS AND LARGE HAIL.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY.

A STRONG COLD FRONT WILL APPROACH THE REGION LATE FRIDAY. THERE
IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ASSOCIATED WITH THE
FRONT. DAMAGING WIND GUSTS WILL BE THE PRIMARY THREAT.

.SPOTTER INFORMATION STATEMENT...

SKYWARN SPOTTERS ARE REQUESTED TO FORWARD ANY REPORTS OF LARGE
HAIL...DAMAGING WINDS...TORNADOES OR FLASH FLOODING TO OUR OFFICE.

ARK

In the hours before

Special weather statement, Aug 8, 11:32 AM EST, 1 hour 24 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1232 PM EDT WED AUG 8 2012

NCZ035-036-081715-
ALEXANDER-IREDELL-
1232 PM EDT WED AUG 8 2012

...A STRONG THUNDERSTORM WILL AFFECT CENTRAL IREDELL AND SOUTHEASTERN
ALEXANDER COUNTIES THROUGH 115 PM EDT...

AT 1228 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR SCOTTS...OR 9 MILES NORTHWEST OF
STATESVILLE...MOVING SOUTHEAST AT 10 MPH.

THIS STORM WILL IMPACT LOCATIONS NEAR...
  STATESVILLE...

SMALL HAIL...WIND GUSTS OF 40 TO 50 MPH AND TORRENTIAL RAIN ARE
EXPECTED WITH THIS STORM.

LAT...LON 3587 8070 3578 8073 3561 8085 3579 8113
      3580 8113 3581 8114 3583 8115 3582 8119
      3585 8122 3599 8103

JOH

Special weather statement, Aug 8, 11:52 AM EST, 1 hour 4 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1252 PM EDT WED AUG 8 2012

NCZ064-SCZ002-003-081730-
GREENVILLE MOUNTAINS-PICKENS MOUNTAINS-TRANSYLVANIA-
1252 PM EDT WED AUG 8 2012

...A STRONG THUNDERSTORM WILL AFFECT NORTHWESTERN GREENVILLE...
NORTHWESTERN PICKENS AND SOUTHERN TRANSYLVANIA COUNTIES THROUGH 130
PM EDT...

AT 1249 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 3 MILES SOUTH OF BALSAM GROVE...OR 9 MILES WEST
OF BREVARD...MOVING SOUTHEAST AT 10 MPH.

THIS STORM WILL IMPACT LOCATIONS NEAR...
  LAKE TOXAWAY...
  ROSMAN...
  ROCKY BOTTOM...

SMALL HAIL...WIND GUSTS OF 40 TO 50 MPH AND TORRENTIAL RAIN ARE
EXPECTED WITH THIS STORM.

LAT...LON 3519 8297 3521 8296 3528 8282 3505 8259
      3493 8286 3504 8291 3505 8290 3505 8291
      3519 8298

JOH

Special weather statement, Aug 8, 12:52 PM EST, 4 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
152 PM EDT WED AUG 8 2012

NCZ064-SCZ002-081830-
PICKENS MOUNTAINS-TRANSYLVANIA-
152 PM EDT WED AUG 8 2012

...STRONG THUNDERSTORMS WILL AFFECT NORTHWESTERN PICKENS AND
SOUTHERN TRANSYLVANIA COUNTIES THROUGH 230 PM EDT...

AT 148 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 4 MILES NORTHEAST OF ROSMAN...OR 4 MILES
SOUTHWEST OF BREVARD...MOVING SOUTHEAST AT 5 MPH.

ANOTHER STRONG THUNDERSTORM WAS LOCATED SOUTHEAST OF LAKE
TOXAWAY...ALSO DRIFTING SLOWLY SOUTHEAST.

PEOPLE IN NORTHWESTERN PICKENS AND SOUTHERN TRANSYLVANIA COUNTIES...
INCLUDING THE FOLLOWING LOCATIONS...

ROSMAN AND BREVARD...

SHOULD MONITOR THE WEATHER SITUATION CLOSELY. LISTEN FOR POSSIBLE
WARNINGS AND BE PREPARED TO TAKE APPROPRIATE ACTION SHOULD SEVERE
WEATHER THREATEN.

SMALL HAIL...AND WIND GUSTS UP TO 40 MPH ARE EXPECTED WITH THIS
STORM.

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 3528 8285 3523 8261 3522 8260 3515 8259
      3512 8266 3513 8268 3510 8269 3508 8275
      3498 8285 3504 8291 3505 8290 3505 8293
      3512 8300

MOORE

The radar

The Greer radar (KGSP), 72 km away, was scanning. The volume nearest the first event began at 17:56 UTC.

Open the radar archive at this moment

Event by event

5 hail, 5 thunderstorm wind, 1 flash flood. Local standard time, as filed.

Hail, Transylvania

When: August 8, 12:56 PM EST
Where: Transylvania County, 2.15 mi SSE of Oakland
Measured: 0.75 in hail
Reported by: Park/Forest Service
Coordinates: 35.090, -82.970

Penny size hail was reported in Gorges State Park.

Thunderstorm Wind, Iredell

When: August 8, 1:12 PM EST
Where: Iredell County, 2.15 mi SSE of Mooresville
Measured: 50 kt (58 mph) estimated gust
Reported by: Fire Department/Rescue
Coordinates: 35.550, -80.810

Trees were blown down on Shearers Rd.

Hail, Burke

When: August 8, 2:17 PM EST
Where: Burke County, 0.69 mi N of Calvin
Measured: 1 in hail
Reported by: Public
Coordinates: 35.760, -81.750

Quarter size hail was reported about 4 miles west northwest of Morganton.

Thunderstorm Wind, Mecklenburg

When: August 8, 2:26 PM EST
Where: Mecklenburg County, 0.69 mi N of Idlewild
Measured: 50 kt (58 mph) estimated gust
Reported by: Broadcast Media
Coordinates: 35.230, -80.750

Large tree limbs were blown down in the Plaza area.

Thunderstorm Wind, McDowell

When: August 8, 3:05 PM EST to 3:10 PM EST
Where: McDowell County, 1.49 mi SSE of West Marion to 1.45 mi WSW of Glenwood
Measured: 50 kt (58 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 35.630, -82.020

Trees were blown down, blocking I-40 East about 3 miles south of Marion. Multiple trees were also blown down along Goose Creek Rd.

Hail, McDowell

When: August 8, 3:07 PM EST
Where: McDowell County, 1.32 mi ESE of West Marion
Measured: 0.75 in hail
Reported by: Trained Spotter
Coordinates: 35.640, -82.010

Hail, McDowell

When: August 8, 3:30 PM EST
Where: McDowell County, 2.18 mi SW of Glenwood
Measured: 1 in hail
Reported by: Public
Coordinates: 35.600, -82.010

Quarter size hail was reported in the Glenwood community.

Thunderstorm Wind, McDowell

When: August 8, 3:35 PM EST
Where: McDowell County, 2.25 mi E of Sugar Hill
Measured: 55 kt (63 mph) estimated gust
Reported by: Emergency Manager
Coordinates: 35.580, -82.010

Numerous trees were blown down south of the Glenwood community.

Thunderstorm Wind, Cleveland

When: August 8, 3:55 PM EST
Where: Cleveland County, 3.14 mi ENE of Archdale
Measured: 50 kt (58 mph) estimated gust
Reported by: 911 Call Center
Coordinates: 35.200, -81.380

Two large tree limbs were blown down across I-85.

Hail, Haywood

When: August 8, 5:47 PM EST
Where: Haywood County, 1.9 mi SSE of Canton
Measured: 0.88 in hail
Reported by: Public
Coordinates: 35.505, -82.817

Flash Flood, Union

When: August 8, 8:30 PM EST to 10:00 PM EST
Where: Union County, 3.29 mi N of Alton to 3.37 mi N of Alton
Cause: Heavy Rain
Reported by: 911 Call Center
Coordinates: 34.927, -80.521

County communications center reported Medlin Road and Macedonia Church Road were flooded by little Richardson Creek. Water was crossing Charlie Williams Road near the intersection with stack Road and was apparently the result of flooding along Little Richardson Creek.

What these are

Hail: Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.
Thunderstorm Wind: Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.
Flash Flood: Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in North Carolina in 2012 Every state in 2012 This day in weather history Warnings in North Carolina, August 2012

Sources

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: 409142, 409148, 409926, 409153, 409155, 409157, 409158, 409161, 409162, 409163, 409642.