Alert archive / South Carolina / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 67, NWS Greenville-Spartanburg, SC

April 9, 2011York County, South Carolina

NWS Greenville-Spartanburg, SC issued this severe thunderstorm warning at Apr 9, 2011, 5:56 PM EDT for York County, South Carolina. It was in force for 34 min. 4 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Apr 9, 2011, 5:56 PM EDT (21:56 UTC)
Expired: Apr 9, 2011, 6:30 PM EDT
In force: 34 min
Issued by: NWS Greenville-Spartanburg, SC
Area: Storm-based polygon

County York County, SC

The radar

The Columbia radar (KCAE), 111 km from the middle of the area, began a volume at 21:58 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

Time	Report	Where	Remark
Apr 9, 5:58 PM EDT	HAIL 1.75	3 Se Rock Hill, SC	I-77 EXIT 77
Apr 9, 5:58 PM EDT	HAIL 2	Fort Mill, SC
Apr 9, 6:00 PM EDT	HAIL 1.75	Catawba, SC
Apr 9, 6:00 PM EDT	HAIL 1.75	Rock Hill, SC

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

Did it verify

Verified. The Iowa Environmental Mesonet's Cow matched 4 storm reports to this severe thunderstorm warning; the first came 2 minutes after it went out.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Apr 9, 2:44 PM EDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Greensboro/Hi Pt, NC (KGSO), launched 12:00Z, 9.9 hours before the alert went out and 158 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 704 m above ground
0-6 km bulk shear: 55 kt
0-1 km storm-relative helicity: 169 m²/s²
0-3 km storm-relative helicity: 256 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

687 
WUUS52 KGSP 092156
SVRGSP
SCC091-092230-
/O.NEW.KGSP.SV.W.0067.110409T2156Z-110409T2230Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
556 PM EDT SAT APR 9 2011

THE NATIONAL WEATHER SERVICE IN GREENVILLE-SPARTANBURG HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHEASTERN YORK COUNTY IN UPSTATE SOUTH CAROLINA...

* UNTIL 630 PM EDT

* AT 552 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING GOLF BALL SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED 5 MILES
  SOUTH OF FORT MILL...OR 5 MILES EAST OF ROCK HILL...MOVING
  SOUTHEAST AT 35 MPH.

* LOCATIONS IMPACTED INCLUDE...
  CATAWBA...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

PEOPLE IN THE PATH OF THIS SEVERE THUNDERSTORM SHOULD BE ALERT FOR
LARGE HAIL AND DAMAGING WINDS. FREQUENT LIGHTNING AND LOCALLY HEAVY
RAIN CAN OCCUR WITH ANY THUNDERSTORM. SEEK SHELTER INDOORS AWAY FROM
WINDOWS AND DOORS UNTIL THE STORM PASSES.

TO REPORT DAMAGING WINDS...LARGE HAIL...OR FLOODING...THROUGH OUR
AUTOMATED REPORTING SYSTEM...CALL OUR TOLL FREE NUMBER...
1 8 7 7...6 3 3...6 7 7 2.

&&

LAT...LON 3482 8089 3482 8114 3497 8110 3505 8104
      3506 8101 3506 8090 3501 8090 3497 8087
      3491 8086 3491 8087 3484 8086
TIME...MOT...LOC 2156Z 322DEG 32KT 3491 8091

$$

NED

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, 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 this severe thunderstorm warning went out at Apr 9, 2:51 PM EDT, 3 hours 5 minutes earlier.

Area forecast discussion, Apr 9, 2:51 PM EDT, 3 hours 5 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
251 PM EDT SAT APR 9 2011

.SYNOPSIS...
STRONG UPPER RIDGING WILL BUILD ATOP THE REGION FOR SUNDAY BUT GIVE
WAY TO AN APPROACHING COLD FRONT MONDAY NIGHT. HIGH PRESSURE THEN
RETURNS FOR TUESDAY AND WEDNESDAY.

&&

.NEAR TERM /THROUGH SUNDAY/...
THE ENTIRE FORECAST AREA WILL BE IN A CONVECTIVE WATCH THROUGH EARLY
EVENING. THE TOR WATCH REMAINS FOR THE NC MTNS AND FOOTHILLS...WITH
A NEW SEVERE WATCH FARTHER TO THE SE.

WATER VAPOR IMAGERY SHOWS THE POTENT UPSTREAM MCV OVER THE OH
VALLEY...WITH A STRONG MCC AHEAD OF IT. STRONG TO SEVERE CONVECTION
IS DEVELOPING TO THE SOUTH OF THIS FEATURE IN THE VERY UNSTABLE WARM
SECTOR AIRMASS. LAPS CAPE VALUES ARE ALREADY AROUND 3000 J/KG ACROSS
MUCH OF THE AREA...AND ADDITIONAL DEWPOINT RECOVERY IS LIKELY
THROUGH LATE AFTERNOON IN THE SOUTHERLY FLOW. FORCING IS BETTER
NORTH THAN SOUTH THROUGH THE PM HOURS...BUT HEALTHY SRN TIER POPS
WILL BE NEEDED AS OUTFLOWS DEVELOP. THERE IS CONSIDERABLE CIN TO BE
OVERCOME IN THE SOUNDINGS ACROSS SRN SECTIONS...BUT INSTABILITY WILL
BE QUITE STRONG WHEN REALIZED. FREEZING LEVELS AROUND 12 K
FT...STEEP LAPSE RATES ALOFT...AND IMPROVING SHEAR PROFILES WILL
MAKE FOR A ROBUST SEVERE WEATHER THREAT THROUGH THE EARLY EVENING
HOURS. STORM CORES TO 22 OR 23 KFT SHOULD BE SUFFICIENT FOR LARGE
HAIL...AND VERY LARGE HAIL WILL BE POSSIBLE ALONG WITH SIGNIFICANT
WIND DAMAGE.

WARM ADVECTION WILL INCREASE ALONG THE 850 MB BAROCLINIC ZONE
THROUGH THE EVENING HOURS...WITH WARM ADVECTION THE STRONGEST IN THE
DEEPER MOISTURE ACROSS THE NE HALF. THE BEST LATE EVENING POPS WILL
BE FEATURED THERE AS THE MCV MOVES EAST OF THE AREA. PATCHY FOG IS
EXPECTED OVERNIGHT IN AREAS RECEIVING APPRECIABLE RAINFALL...AND MIN
TEMPS SHOULD BE ON THE MILD SIDE DESPITE THE SFC FRONT SAGGING BACK
TO THE SW.

UPPER LEVEL HEIGHTS WILL BUILD SHARPLY OVER THE AREA THE REST OF
TONIGHT THROUGH SUNDAY. 850 MB TEMPS WILL WARM ANOTHER COUPLE OF
DEGREES UNDER THE RIDGE TO PRODUCE A VERY WARM SUNDAY AFTERNOON. A
PLUME OF RICH THETA E AIR IS EXPECTED TO STRETCH ACROSS THE FORECAST
AREA SUN AFTN...BUT A TRIGGER FOR CONVECTION WILL BE HARD TO FIND.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
AT 215 PM SATURDAY...LARGER SCALE LIFT AHEAD OF DEVELOPING SOUTHERN
STREAM S/WV WILL OVERSPREAD THE CWFA LATE MONDAY INTO MONDAY NIGHT.
IT IS STILL LIKELY THAT A ROUND OF FRONTAL BAND PCPN WILL AFFECT THE
AREA DURING THIS PERIOD...HOWEVER...JUST LIKE WHAT WAS FCST
YESTERDAY...TSTM MAGNITUDE IS QUESTIONABLE...WITH THE 09 UTC SREF
PROBABILITIES OF CAPE VALUES OF AT LEAST 1000 J/KG STILL VERY LOW.

PRE-FRONTAL PRESSURE GRADIENT TIGHTENS ENUF TO DEVELOP BREEZY CONDS
MONDAY AFTERNOON...AND DESPITE ENCROACHING CLOUDS...ANOTHER WARM DAY
IS ON TAP. ENCROACHING DRY SLOT TUESDAY MORNING EXPECTED TO QUICKLY
DIMINISH PCPN CHANCES DESPITE AXIS OF MID-LVL WAVE NOT TRANSLATING
DOWNSTREAM OF THE CWFA UNTIL LATER IN THE DAY. WILL SHOOT FOR
INCREASING SUNSHINE WITH MAX TEMPS CLOSER TO CLIMO...ALBEIT NEAR
5 DEG F ABOVE NORMAL.

&&

.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
AT 230 PM SATURDAY...IT LOOKS LIKE THERE IS ENUF AGREEMENT BETWEEN
THE 12 UTC OP GFS AND THE LATEST HPC EXTENDED PROGS IN DEPICTING
DEEP LAYERED RIDGING ATOP THE EASTERN CONUS FOR WEDNESDAY TO PROVIDE
DRY AND SEASONABLY MILD WX. THE ONSET OF INCREASINGLY MOIST GULF TAP
AHEAD OF ENCROACHING PLAINS SYSTEM IS SLATED FOR THURSDAY...BUT
WOULD EXPECT ANOTHER ESSENTIALLY DRY AND SEASONABLY MILD DAY.

IT REMAINS TO BE SEEN HOW QUICKLY AND TO WHAT DEGREE AFOREMENTIONED
SYSTEM GETS WRAPPED UP AS IT HEADS TOWARD THE GREAT LAKES BY THE END
OF THE PERIOD. THE ATTENDANT MODERATELY FORCED COLD FRONT WILL
STEADILY ENCROACH AS WELL AND IT/S PROBABLE THAT THE MILD AND
MOISTENING AIRMASS WILL PROVIDE FUEL FOR DAILY TSTM CHANCES IN THE
WARM SECTOR.

&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
AT KCLT...THE FIRST ROUND OF CONVECTION MOVING OFF THE BLUE RIDGE
EARLY THIS AFTERNOON IS STILL A FEW HOURS AWAY FROM THREATENING
KCLT. SHOWERS MAY FILL IN ACROSS THE PIEDMONT IN THE INTERIM...WITH
THE BEST CHANCE OF TSRA NOW LIKELY STARTING AROUND 21Z. CONVECTION
WITH THE PASSING UPPER WAVE SHOULD MOVE EAST OF THE AREA BY LATE
EVENING. LOW LEVEL NE FLOW BEHIND A WEAK FRONT SHOULD BRING MVFR
CLOUDS BACK INTO THE PICTURE OVERNIGHT. THE LOW CLOUDS WILL SCATTER
CIRCA 14Z WITH MIXING ON SUNDAY AS A RIDGE BUILDS IN ALOFT AND LOW
LEVEL FLOW BECOMES SE ONCE AGAIN.

ELSEWHERE...THUNDER CHANCES WILL BE GREATEST FROM KAVL TO KHKY
THROUGH THE AFTERNOON HOURS...WITH TSRA INCREASING AT THE SC TAF
SITES MAINLY AROUND 21Z. VFR LEVEL CB CIGS ARE EXPECTED...WITH WINDS
GENERALLY S TO SW THROUGH EVENING. A PUSH FROM THE NE IS AGAIN
EXPECTED AS A WEAK SFC BOUNDARY DIPS BACK TO THE SW...BUT ANY
ASSOCIATED MVFR CLOUDS SHOULD IMPACT MAINLY KHKY AND KAVL...AND
POSSIBLY FLIRT WITH THE UPSTATE SITES OVERNIGHT. LOW CLOUDS WILL
SCATTER UNDER THE BUILDING RIDGE SUNDAY MORNING.

OUTLOOK....STRONGER RIDGING RETURNS ON SUNDAY. SCT SHRA/TSTMS MAY
ARRIVE WITH A COLD FRONT MONDAY. DRIER HIGH PRES IS EXPECTED TUE AND
WED.

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.

&&

SYNOPSIS...CSH
NEAR TERM...HG
SHORT TERM...CSH
LONG TERM...CSH
AVIATION...HG

Hazardous weather outlook, Apr 9, 2:50 PM EDT, 3 hours 6 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
250 PM EDT SAT APR 9 2011

GAZ010-017-018-026-028-029-NCZ035>037-056-057-068>072-082-SCZ001>014-
019-101900-
RABUN-HABERSHAM-STEPHENS-FRANKLIN-HART-ELBERT-ALEXANDER-IREDELL-
DAVIE-CATAWBA-ROWAN-CLEVELAND-LINCOLN-GASTON-MECKLENBURG-CABARRUS-
UNION NC-OCONEE MOUNTAINS-PICKENS MOUNTAINS-GREENVILLE MOUNTAINS-
GREATER OCONEE-GREATER PICKENS-GREATER GREENVILLE-SPARTANBURG-
CHEROKEE-YORK-ANDERSON-ABBEVILLE-LAURENS-UNION SC-CHESTER-GREENWOOD-
250 PM EDT SAT APR 9 2011

...SEVERE THUNDERSTORM WATCH 114 IN EFFECT UNTIL 9 PM EDT THIS
EVENING...

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

.DAY ONE...THIS AFTERNOON AND 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...

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

NCZ033-048>053-058-059-062>065-501>510-101900-
AVERY-MADISON-YANCEY-MITCHELL-SWAIN-HAYWOOD-BUNCOMBE-GRAHAM-
NORTHERN JACKSON-MACON-SOUTHERN JACKSON-TRANSYLVANIA-HENDERSON-
CALDWELL MOUNTAINS-GREATER CALDWELL-BURKE MOUNTAINS-GREATER BURKE-
MCDOWELL MOUNTAINS-EASTERN MCDOWELL-RUTHERFORD MOUNTAINS-
GREATER RUTHERFORD-POLK MOUNTAINS-EASTERN POLK-
250 PM EDT SAT APR 9 2011

...TORNADO WATCH 113 IN EFFECT UNTIL 9 PM EDT THIS EVENING...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN NORTH CAROLINA.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE
INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS.

   TORNADO WATCH.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

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

In the hours before

Local storm report, Apr 9, 5:44 PM EDT, 12 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
544 PM EDT SAT APR 09 2011

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0530 PM     HAIL             CLOVER                  35.11N 81.23W
04/09/2011  E1.25 INCH       YORK               SC   PUBLIC

&&

HG

Local storm report, Apr 9, 5:45 PM EDT, 11 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
545 PM EDT SAT APR 09 2011

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0533 PM     HAIL             CLOVER                  35.11N 81.23W
04/09/2011  E2.00 INCH       YORK               SC   PUBLIC

&&

HG

Local storm report, Apr 9, 5:46 PM EDT, 10 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
546 PM EDT SAT APR 09 2011

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0530 PM     HAIL             GASTONIA                35.25N 81.17W
04/09/2011  E1.75 INCH       GASTON             NC   PUBLIC

&&

HG

Local storm report, Apr 9, 5:47 PM EDT, 9 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
547 PM EDT SAT APR 09 2011

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0538 PM     HAIL             2 E LAKE WYLIE          35.11N 81.02W
04/09/2011  E1.75 INCH       MECKLENBURG        NC   AMATEUR RADIO

&&

Local storm report, Apr 9, 5:49 PM EDT, 7 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
549 PM EDT SAT APR 09 2011

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0545 PM     HAIL             5 WNW GASTONIA          35.29N 81.25W
04/09/2011  E2.75 INCH       GASTON             NC   TRAINED SPOTTER

            HW 274 AND HOLLAND MEMORIAL CHURCH RD

&&

Local storm report, Apr 9, 5:53 PM EDT, 3 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
553 PM EDT SAT APR 09 2011

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0538 PM     HAIL             1 NE CHERRYVILLE        35.39N 81.36W
04/09/2011  E1.25 INCH       GASTON             NC   TRAINED SPOTTER

            HAIL REPORTED ON WOODVALE DRIVE IN CHERRYVILLE.

&&

BSH

The office that day

Everything else NWS Greenville-Spartanburg, SC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 9, 3:43 PM EDT	Severe Thunderstorm Warning	GSP	Oconee	62 min
Apr 9, 4:29 PM EDT	Severe Thunderstorm Warning	GSP	Oconee, Pickens	46 min
Apr 9, 4:52 PM EDT	Severe Thunderstorm Warning	GSP	Anderson, Greenville, Pickens	53 min
Apr 9, 5:24 PM EDT	Tornado Warning	GSP	York	36 min
Apr 9, 5:26 PM EDT	Severe Thunderstorm Warning	GSP	York	64 min
Apr 9, 5:40 PM EDT	Severe Thunderstorm Warning	GSP	Anderson, Greenville, Laurens	48 min
Apr 9, 5:53 PM EDT	Severe Thunderstorm Warning	GSP	York	52 min
Apr 9, 6:06 PM EDT	Tornado Warning	GSP	York	12 min
Apr 9, 6:17 PM EDT	Severe Thunderstorm Warning	GSP	York	58 min
Apr 9, 7:00 PM EDT	Severe Thunderstorm Warning	GSP	Chester, York	12 min
Apr 9, 7:25 PM EDT	Severe Thunderstorm Warning	GSP	York	38 min
Apr 9, 7:26 PM EDT	Severe Thunderstorm Warning	GSP	Cherokee	41 min
Apr 9, 7:53 PM EDT	Severe Thunderstorm Warning	GSP	Cherokee, York	67 min

Nearby

Severe Thunderstorm Warnings in South Carolina, 2011 Every severe thunderstorm warning in 2011

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.