Alert archive / North Carolina / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 436, NWS Greenville-Spartanburg, SC

June 21, 2011Henderson County, Transylvania County, North Carolina

NWS Greenville-Spartanburg, SC issued this severe thunderstorm warning at Jun 21, 2011, 2:01 PM EDT for Henderson County, Transylvania County, North Carolina. It was in force for 59 min. 1 report 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
Jun 21, 2011, 2:01 PM EDT (18:01 UTC)
Expired
Jun 21, 2011, 3:00 PM EDT
In force
59 min
Issued by
NWS Greenville-Spartanburg, SC
Area
Storm-based polygon

Counties Henderson County, NC, Transylvania County, NC

The radar

The Greer radar (KGSP), 67 km from the middle of the area, began a volume at 18:03 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

TimeReportWhereRemark
Jun 21, 2:30 PM EDTTSTM WND DMG5 Ne Brevard, NCTREES REPORTED DOWN ON HWY 276 NE OF BREVARD. TIME ESTIMATED FROM RADAR.

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 one storm report to this severe thunderstorm warning; the first came 29 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 nearest sounding before it

Greensboro/Hi Pt, NC (KGSO), launched 12:00Z, 6.0 hours before the alert went out and 270 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-pSkew-T log-p diagram, Greensboro/Hi Pt, NC at 12:00Z on 2011-06-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 508 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Greensboro/Hi Pt, NC at 12:00Z on 2011-06-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 35 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
508 J/kg
Mixed-layer CIN
-164 J/kg
Mixed-layer LCL
1168 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
35 m²/s²
0-3 km storm-relative helicity
93 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.7

Open this sounding in Storm Lab

The text

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

509 
WUUS52 KGSP 211801
SVRGSP
NCC089-175-211900-
/O.NEW.KGSP.SV.W.0436.110621T1801Z-110621T1900Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
201 PM EDT TUE JUN 21 2011

THE NATIONAL WEATHER SERVICE IN GREENVILLE-SPARTANBURG HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WESTERN HENDERSON COUNTY IN WESTERN NORTH CAROLINA...
  NORTHERN TRANSYLVANIA COUNTY IN WESTERN NORTH CAROLINA...

* UNTIL 300 PM EDT

* AT 200 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR
  BALSAM GROVE...OR 8 MILES WEST OF BREVARD...MOVING EAST AT 15 MPH.

* OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
  LITTLE RIVER...ETOWAH...MOUNTAIN HOME AND MILLS RIVER

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 3531 8283 3536 8279 3540 8274 3542 8268
      3542 8250 3521 8245 3513 8289 3529 8291
TIME...MOT...LOC 1801Z 258DEG 13KT 3523 8284

$$

JPT
1 follow-up statement
393 
WWUS52 KGSP 211835
SVSGSP

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
235 PM EDT TUE JUN 21 2011

NCC089-175-211900-
/O.CON.KGSP.SV.W.0436.000000T0000Z-110621T1900Z/
HENDERSON NC-TRANSYLVANIA NC-
235 PM EDT TUE JUN 21 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 300 PM EDT
FOR NORTHEASTERN TRANSYLVANIA AND WESTERN HENDERSON COUNTIES...

AT 230 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS
LOCATED 3 MILES NORTH OF BREVARD...MOVING NORTHEAST AT 20 MPH.

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO LITTLE
RIVER...ETOWAH...MOUNTAIN HOME AND MILLS RIVER

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS SEVERE THUNDERSTORM WARNING HAS BEEN ISSUED BECAUSE BRIEF
PERIODS OF DAMAGING WINDS AND/OR LARGE HAIL ARE EXPECTED OVER SMALL
AREAS. THIS STORM WAS ALSO CAUSING INTENSE LIGHTNING AND TORRENTIAL
RAINFALL. SEEK SHELTER INDOORS UNTIL THE STORM PASSES.

&&

LAT...LON 3524 8246 3514 8284 3529 8289 3531 8283
      3536 8279 3540 8274 3542 8268 3542 8250
TIME...MOT...LOC 1835Z 246DEG 16KT 3529 8270

$$

JPT

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 Jun 21, 11:11 AM EDT, 2 hours 50 minutes earlier.

Area forecast discussion, Jun 21, 11:11 AM EDT, 2 hours 50 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1111 AM EDT TUE JUN 21 2011

.SYNOPSIS...
A WEAK RIDGE OF HIGH PRESSURE WILL SLOWLY MOVE EAST OF THE AREA AS A
COLD FRONT SLOWLY APPROACHES FROM THE WEST ON WEDNESDAY. THE FRONT
STALLS AS IT REACHES THE FORECAST AREA THURSDAY THROUGH FRIDAY. THE
FRONT WILL LINGER IN PLACE OVER THE WEEKEND TO KEEP CONDITIONS
UNSETTLED.

&&

.NEAR TERM /THROUGH TONIGHT/...
SLIGHTLY LESS MIXING OF DEWPOINTS TODAY COMPARED TO YESTERDAY SHOULD
ALLOW MORE SCATTERED MTN CONVECTION TO DEVELOP THROUGH THE AFTERNOON
IN IMPROVING SW FLOW ALOFT. WITH THE DEVELOPING TROUGH WELL TO THE
WEST...AND THE WARM FRONT NOW NORTH OF THE AREA...FORCING WILL BE
QUITE A BIT LESS OUTSIDE OF THE MTNS. FOOTHILL AND PIEDMONT
CONVECTIVE COVERAGE WILL THUS DEPEND MORE ON OUTFLOWS RUNNING EAST
OF THE MTNS LATE TODAY. WILL RAMP UP POPS IN THE MTNS AND NRN
FOOTHILLS...AND TOUCH THEM UP SLIGHTLY ELSEWHERE GIVEN THE
HIGH CAPE VALUES ON THE LATEST LAPS ANALYSIS. OF PARTICULAR INTEREST
IS THE VERY HIGH DCAPE VALUES...1300 TO 1500...IN THE SRN HALF OF
THE CWA THIS AFTN...WITH EQUIVALENT POTENTIAL TEMP LAPSES RUNNING
NEAR 30 K THROUGHOUT. THE SLIGHT SEVERE RISK AND HWO WORDING STILL
APPEARS WARRANTED. WITH EXCELLENT INSOLATION THIS AFTN...SOUTHEAST
PIEDMONT HEAT INDEX VALUES SHOULD REACH 100 TO 103.

HEIGHTS WILL CONTINUE TO FALL FROM THE WEST OVERNIGHT. AN ADDITIONAL
ROUND OF THUNDERSTORMS COULD MAKE A RUN AT THE SRN
APPALACHIANS...BUT IT SHOULD EXHIBIT A WEAKENING TREND. PATCHY MTN
VALLEY FOG IS LIKELY ONCE AGAIN.

&&

.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
AS OF 300 AM TUESDAY...AN UPPER LOW MOVING FROM THE MIDWEST INTO THE
GREAT LAKES REGION ON WED WILL BEGIN TO BREAK DOWN THE SHALLOW UPPER
RIDGE IN PLACE ACROSS THE SOUTHEAST. LOW LEVEL FLOW SHOULD INCREASE
FROM THE SOUTHWEST THROUGH THE DAY...ALONG WITH A STEADY MOISTURE
RETURN IN THE PROFILES. CONVECTIVE CHANCES WED THROUGH WED NIGHT
WILL BE BEST ACROSS THE MOUNTAINS...BUT SCT CONVECTION SHOULD
DEVELOP ELSEWHERE AS WELL. TEMPS WILL REMAIN WARM...BUT WITH THE
RIDGE BREAKING DOWN THE FORECAST WILL NOT BE AS WARM AS THE MAV
NUMBERS FOR NOW.

HEIGHTS WILL FALL FURTHER ON THU AS AN UPPER JET LET LIKELY RIDES
NORTHEAST ALONG THE SRN APPALACHIANS AHEAD OF THE DEVELOPING LONG
WAVE TROUGH...AND WEAK SHORTWAVES BEGIN TO BRUSH THE MOUNTAINS. AT
THE SFC...A COLD FRONT WILL START TO PUSH SOUTHEAST TOWARD THE AREA
FROM THE OH VALLEY. THE GFS HAS THE FRONT JUMP THE MTNS AND DEVELOP
ALONG THE COAST. SINCE THE NAM/SREF DO NOT...HAVE CHC POP DEVELOP
ACROSS THE AREA INSTEAD OF A NEARLY DRY FCST LIKE THE GFS. STRONG
STORMS MAY DEVELOP THROUGH THE AFTERNOON AS DEEPER LAYER LAPSE
RATES INCREASE. THE INCREASED CLOUDS...HOWEVER...COULD LIMIT SFC
BASED INSTABILITY SOMEWHAT...AND TEMPS SHOULD BE AT LEAST A CATEGORY
COOLER THU AFTN.

THE UPPER TROF MOVES TOWARD THE AREA BUT REMAINS TO OUR WEST. THIS
KEEPS US IN A FAVORABLE POSITION FOR SHORT WAVE FORCING AND UPPER
JET DIVERGENCE. EVEN THO THE SFC FRONT WILL HAVE MOVED EAST OF THE
AREA...MOISTURE AND INSTABILITY INCREASE THRU THE DAY. EXPECT
SCATTERED CONVECTION TO DEVELOP ONCE AGAIN. HIGHS SHUD BE NEARLY
STEADY FROM FRI.

&&

.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
AS OF 315 AM TUESDAY...SOME VARIABILITY REMAINS IN THE MODEL
HANDLING OF THE GREAT LAKES LOW PRES THRU THE WEEKEND. THE GENERAL
CONSENSUS IS THAT THE SYSTEM WILL SLOWLY LIFT NE INTO CANADA BUT
WITH SHORTWAVES OVER THE ERN CONUS CARVING OUT A PERSISTENT TROUGH
OVER THE EAST THROUGH THE PERIOD. THE LOW LEVEL WESTERLY FLOW
RESULTING FROM THIS SOLUTION WILL LIKELY ALLOW A COLD FRONT TO STALL
AND LINGER IN THE VICINITY OF THE FORECAST AREA THROUGH THE WEEKEND
INTO MONDAY. A MAINLY DIURNAL PATTERN TO THE CONVECTION IS EXPECTED
SATURDAY THROUGH MONDAY...BUT OVERNIGHT ISOLATED TO SCATTERED
CONVECTION COULD BE POSSIBLE WITH ANY PASSING SHORTWAVES. HOWEVER...
IT IS NOT POSSIBLE TO TIME THESE SHORTWAVES AT PRESENT. MAX AND MIN
TEMPERATURES SHOULD RUN ABOUT A CATEGORY ABOVE NORMAL EACH DAY.

&&

.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
AT KCLT...SKIES HAVE CLEARED OUT AS MCS DEBRIS HAS PASSED TO THE
EAST OR DISSIPATED. LIGHT SE WINDS SHOULD TURN MORE S TO SW WITH
MIXING THROUGH THE AFTN. NEARLY ALL THE MESOSCALE MODELS ARE NOW
TRYING TO DEVELOP CONVECTION NEAR THE BLUE RIDGE AND SEND THIS
EASTWARD ACROSS THE CHARLOTTE VICINITY. HOWEVER...THE MODEL
PERFORMANCE HAS BEEN POOR OVER THE PAST SEVERAL DAYS IN THIS
REGARD...SO WILL WAIT UNTIL MTN CONVECTION DEVELOPS TODAY AND THEN
TRY TO TIME ANY RUN OUT OVER THE PIEDMONT AT THAT POINT. ASIDE FROM
ANY ISOLATED THUNDERSTORMS...EXPECT VFR CONDITIONS THROUGH THE
PERIOD.

ELSEWHERE...ISOLATED TO SCATTERED CONVECTION WILL LIKELY DEVELOP
ACROSS THE MTNS FIRST THIS AFTN...THEN POSSIBLY MOVE OUT OVER THE
FOOTHILLS THROUGH EARLY EVENING. THE OCCURRENCE OF THUNDER IS TOO
UNCERTAIN TO TIME...BUT A CB CLOUD GROUP WILL LIKELY BE NEEDED WITH
THE KAVL TAF AT 18Z. OTHERWISE...EXPECT A SCATTERED CUMULUS FIELD
WITH SFC WINDS TURNING MORE S TO SW WITH TIME. MVFR TO TEMPO IFR FOG
MAY BE FORECAST TOWARD DAYBREAK WED PENDING NEW INCOMING MODEL MOS.

OUTLOOK...GENERALLY VFR THROUGH THE END OF THE WEEK EXCEPT FOR LOCAL
RESTRICTIONS IN AFTERNOON/EVENING THUNDERSTORMS EACH DAY.
ALSO...MOUNTAIN VALLEY FOG POSSIBLE EACH MORNING TOWARD DAWN.

&&

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

&&

SYNOPSIS...RWH
NEAR TERM...HG
SHORT TERM...RWH
LONG TERM...HG/RWH
AVIATION...HG
Hazardous weather outlook, Jun 21, 11:12 AM EDT, 2 hours 49 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1112 AM EDT TUE JUN 21 2011

GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065-
068>072-082-501>510-SCZ001>014-019-221515-
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-
1112 AM EDT TUE JUN 21 2011

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

.DAY ONE...THIS AFTERNOON AND TONIGHT.

ISOLATED TO SCATTERED THUNDERSTORMS ARE EXPECTED THIS AFTERNOON
AND EVENING...MAINLY NORTHWEST OF INTERSTATE 85. THE MAIN THREAT
FROM THESE STORMS WILL BE CLOUD TO GROUND LIGHTNING...GUSTY WINDS
AND BRIEF HEAVY RAINFALL. A FEW THUNDERSTORMS COULD PRODUCE
DAMAGING WIND GUSTS AND LARGE HAIL.

.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 LARGE
HAIL...DAMAGING WINDS...TORNADOES OR FLASH FLOODING TO OUR OFFICE.

In the hours before

Special weather statement, Jun 21, 1:26 PM EDT, 35 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
126 PM EDT TUE JUN 21 2011

NCZ064-065-211815-
HENDERSON-TRANSYLVANIA-
126 PM EDT TUE JUN 21 2011

...A STRONG THUNDERSTORM WILL AFFECT NORTHEASTERN TRANSYLVANIA AND
WESTERN HENDERSON COUNTIES THROUGH 215 PM EDT...

AT 118 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 5 MILES NORTHWEST OF BREVARD...MOVING EAST AT 10
MPH.

SMALL HAIL...AND WIND GUSTS OF 30 TO 40 MPH ARE EXPECTED WITH THIS
STORM.

LAT...LON 3535 8279 3545 8267 3526 8257 3518 8280
      3530 8285

JPT
Special weather statement, Jun 21, 1:35 PM EDT, 26 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
135 PM EDT TUE JUN 21 2011

NCZ048-049-211815-
MADISON-YANCEY-
135 PM EDT TUE JUN 21 2011

...A STRONG THUNDERSTORM WILL AFFECT MADISON AND WESTERN YANCEY
COUNTIES THROUGH 215 PM EDT...

AT 135 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 3 MILES NORTH OF SPRING CREEK...OR 11 MILES WEST
OF MARSHALL...MOVING NORTHEAST AT 20 MPH.

* OTHER LOCATIONS AFFECTED INCLUDE BUT ARE NOT LIMITED TO
  WHITEROCK...WALNUT...SWISS...SPRING CREEK...MARSHALL...LUCK...HOT
  SPRINGS...FAUST AND ALLENSTAND.

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

LAT...LON 3607 8262 3604 8259 3597 8260 3596 8256
      3600 8247 3589 8240 3571 8290 3582 8296
      3584 8292 3588 8291 3593 8292 3596 8286
      3593 8281 3599 8279

JPT

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 21, 1:26 PM EDTSpecial Weather StatementGSPTransylvania49 min
Jun 21, 1:35 PM EDTSpecial Weather StatementGSPMadison40 min
Jun 21, 1:50 PM EDTSevere Thunderstorm WarningGSPBuncombe55 min
Jun 21, 1:51 PM EDTSevere Thunderstorm WarningGSPMadison, Yancey54 min
Jun 21, 2:08 PM EDTSevere Thunderstorm WarningGSPMacon67 min
Jun 21, 3:09 PM EDTSevere Thunderstorm WarningGSPBuncombe, Henderson, McDowell, Rutherford66 min
Jun 21, 3:19 PM EDTSevere Thunderstorm WarningGSPAvery, Burke, Caldwell, McDowell, Mitchell, Yancey56 min
Jun 21, 3:57 PM EDTSevere Thunderstorm WarningGSPAvery, Burke, Caldwell, McDowell63 min
Jun 21, 4:02 PM EDTSevere Thunderstorm WarningGSPBuncombe, Haywood, Madison42 min
Jun 21, 4:41 PM EDTSevere Thunderstorm WarningGSPCaldwell64 min
Jun 21, 5:33 PM EDTSevere Thunderstorm WarningGSPAlexander42 min
Jun 21, 5:49 PM EDTSpecial Weather StatementGSPPolk41 min
Jun 21, 6:29 PM EDTSevere Thunderstorm WarningGSPCleveland, Rutherford61 min
Jun 21, 7:04 PM EDTSevere Thunderstorm WarningGSPCatawba, Cleveland, Gaston, Lincoln56 min

Nearby

Severe Thunderstorm Warnings in North Carolina, 2011Every 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.