Alert archive / South Carolina / Severe Thunderstorm Warnings in 2007

Severe Thunderstorm Warning 345, NWS Greenville-Spartanburg, SC

August 17, 2007Oconee County, South Carolina

NWS Greenville-Spartanburg, SC issued this severe thunderstorm warning at Aug 17, 2007, 10:06 PM EDT for Oconee County, South Carolina. It was in force for 24 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Aug 17, 2007, 10:06 PM EDT (02:06 UTC)
Expired
Aug 17, 2007, 10:30 PM EDT
In force
24 min
Issued by
NWS Greenville-Spartanburg, SC
Area
Counties, with a storm outline in the text

County Oconee County, SC

The radar

The Greer radar (KGSP), 79 km from the middle of the area, began a volume at 02:10 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.

The nearest sounding before it

Peachtre/Fal Fld, GA (KFFC), launched 00:00Z, 2.1 hours before the alert went out and 203 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, Peachtre/Fal Fld, GA at 00:00Z on 2007-08-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 106 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, Peachtre/Fal Fld, GA at 00:00Z on 2007-08-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 60 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
106 J/kg
Mixed-layer CIN
-287 J/kg
Mixed-layer LCL
1491 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
60 m²/s²
0-3 km storm-relative helicity
84 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

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 Aug 17, 9:15 PM EDT, 51 minutes earlier.

Area forecast discussion, Aug 17, 9:15 PM EDT, 51 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
915 PM EDT FRI AUG 17 2007

.SYNOPSIS...
A WEAK COLD FRONT WILL CONTINUE TO PUSH SOUTHEAST OF THE AREA
TONIGHT AS HIGH PRESSURE BUILDS IN FROM THE GREAT LAKES. UPPER LEVEL
RIDGING WILL BUILD OVER THE REGION THROUGH THE MIDDLE OF NEXT WEEK.

&&

.NEAR TERM /THROUGH SATURDAY/...
OUTSIDE OF ISOLD CONVECTION FAR S CWA SHORTLY AFTER 9 PM... SKIES
ARE CLEARING ACROSS MOST OF AREA. WITH WEAK OUTFLOW BOUNDARIES OVER
S CWA AND RESIDUAL MOISTURE...WILL KEEP A SMALL AREA OF SLIGHT CHC
POP ALONG S FRINGE UNTIL MIDNIGHT. LOWS SHOULD BE A FEW DEGREES
LOWER THAN THE PAST FEW NIGHTS BUT STILL ABOVE AVG.

DRY FORECAST SATURDAY AS DRIER AIR MOVES INTO THE AREA. HI TEMPS
WILL BE COOLER THAN THE PAST FEW DAYS...BUT STILL ABOVE AVG. UPPER
RIDGING BUILDS BACK INTO THE AREA WITH THICKNESSES AND H85 TEMPS
REMAINING ABOVE NORMAL. LOOK FOR HIGHS RANGING FROM THE UPPER 90S
DOWN NEAR GREENWOOD AND ABBEVILLE...TO LOW 90S UP AROUND HICKORY AND
STATESVILLE. TEMPS IN THE MTNS WILL BE MOSTLY IN THE UPPER 70S AND
80S...BUT AROUND 90 IN LOWER MTN VALLEYS.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
BOTH THE GFS AND THE NAM DEPICT SOME UPGLIDE MOISTURE DEVELOPING
NORTH OF WEAK FRONTAL BOUNDARY BY SUNDAY MORNING. IN FACT...THE NAM
INDICATES A COLD AIR DAMMING-TYPE SETUP DURING THE DAY SUNDAY...AND
MET GUIDANCE IS ABOUT 10 DEGREES COOLER THAN THE MAV. IT SEEMS
UNLIKELY THAT WIDESPREAD...PERSISTENT LOW CLOUDS WILL AFFECT THE
AREA THROUGH THE DAY SUNDAY...AS THE MODELS DEPICT THIS AREA OF
MOISTURE AS BEING TRANSIENT...AS OPPOSED TO LOCKING IT IN OVER THE
AREA. (NOT TO MENTION UPGLIDE WILL BE WEAK AND THE AIRMASS WON/T BE
ALL THAT STABLE.) THEREFORE...WE WILL NUDGE MAX TEMPS TOWARD THE
WARMER MAV NUMBERS...BUT UNDERCUT THESE BY A COUPLE OF DEGREES...AS
IT SEEMS LIKE THERE SHOULD BE AT LEAST A BRIEF PERIOD OF LOW
STRATUS...ESP ACROSS THE EASTERN ZONES.

WITH WEAK BOUNDARY STILL IN THE AREA AND SOME MOISTURE AROUND...WE
WILL CONTINUE TO CARRY SLIGHT CHANCE POPS ACROSS THE REGION SUN
AFTERNOON...ALTHOUGH MODEL INSTABILITY IS NOT ALL THAT IMPRESSIVE.

FOR SUNDAY NIGHT...THE NAM AND THE GFS ARE AT ODDS WITH HOW FAR
SOUTH FRONTAL BOUNDARY ASSOCIATED WITH DEEPENING EASTERN TROUGH WILL
PENETRATE BEFORE STALLING OUT. THE GFS BRINGS MOISTURE ASSOCIATED
WITH THIS FEATURE TO THE NC/VA BORDER. MEANWHILE...THE NAM HOLDS THE
BETTER MOISTURE ACROSS SOUTHERN NEW ENGLAND INTO THE GREAT LAKES.
QUITE A DISCREPANCY. REGARDLESS OF WHICH SOLUTION VERIFIES CLOSER TO
REALITY...IT REALLY DOESN/T MATTER AS FAR AS OUR CWFA IS CONCERNED.
THE GFS SOLUTION SUGGESTS THAT MCS ACTIVITY COULD BRUSH THE FAR
NORTHERN ZONES...BUT THIS ONLY WARRANTS A SLIGHT CHANCE ATTM.

UPPER HIGH CENTERED OFF THE GA COAST WILL KEEP THE BETTER FORCING
AND MOISTURE NORTH OF THE REGION FOR MONDAY...SO THE POP WILL BE
SLIGHT CHANCE AT BEST FOR DIURNAL CONVECTION.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
THE EXTENDED PERIOD BEGINS WITH AN UPPER HIGH CENTERED OVER THE
SOUTHEAST...WITH A RIDGE AXIS EXTENDING NORTHWARD INTO CENTRAL
CANADA. THIS UPPER HIGH WILL RETROGRADE SLIGHTLY WESTWARD AND REMAIN
THE DOMINANT FEATURE THROUGH THURS MORNING. BY FRI...A DEVELOPING
LOW AMPLITUDE TROF OVER THE CENTRAL CONUS WILL BEGIN TO ERODE THE
WESTERN PERIPHERY OF THE RIDGE FOR THE WEEKEND. BEST DEEP LAYER
MOISTURE LOOKS TO REMAIN NORTH OF THE FA UNTIL LATE IN THE PERIOD.
ACCORDINGLY...POPS ARE QUITE LOW WITH RIDGE IN CONTROL...LACK OF
DEEP LAYER MOISTURE AND INSTABILITY. SLGHT CHC POPS ARE ADVERTISED
EVERYWHERE BY LATE IN THE EXTENDED AS THE RIDGE BREAKS DOWN. TEMPS
THROUGHOUT THE PERIOD CONTINUE WARM...RUNNING 4-5 DEGREES ABOVE
CLIMO NORMALS.

&&

.AVIATION /01Z SATURDAY THROUGH WEDNESDAY/...
FRONT AND ASSOC CONVECTION HAVE MOVED WELL S OF TAF SITES WITH SKIES
CLEARING OVER TERMINAL AREAS. EXPECT LIGHT N TO NE WINDS OVERNIGHT.
HAZE MAY STILL GO MVFR VCNTY KCLT BRIEFLY THIS EVE BUT SHOULD
INPROVE IN LIGHT NE FLOW OVERNIGHT. KAVL WILL COME WITHIN A FEW
DEGREES OF CROSSOVER TEMP TONIGHT SO HAVE MVFR FOG/HAZE THERE LATE
TONIGHT THRU EARLY MORNING HOURS...WITH BRIEF TEMPO IFR AROUND
DAYBREAK.

AVIATION OUTLOOK...LOOK FOR GENERALLY DRY CONDITIONS WITH JUST A
SLIGHT CHANCE OF SHWRS/TSTMS SUN THRU WED. EARLY MORNING MVFR FOG
AND HAZE ARE POSSIBLE EACH DAY...MAINLY AT KAVL.

&&

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

&&

SYNOPSIS...RB
NEAR TERM...RB
SHORT TERM...JDL
LONG TERM...BSH
AVIATION...RB
Hazardous weather outlook, Aug 17, 3:50 PM EDT, 6 hours 16 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
350 PM EDT FRI AUG 17 2007

GAZ010-017-018-026-028-NCZ033-035-037-048>053-056-058-059-062>065-
068-501>510-SCZ001>008-010-182000-
RABUN-HABERSHAM-STEPHENS-FRANKLIN-HART-AVERY-ALEXANDER-DAVIE-MADISON-
YANCEY-MITCHELL-SWAIN-HAYWOOD-BUNCOMBE-CATAWBA-GRAHAM-
NORTHERN JACKSON-MACON-SOUTHERN JACKSON-TRANSYLVANIA-HENDERSON-
CLEVELAND-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-ANDERSON-
350 PM EDT FRI AUG 17 2007

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 THUNDERSTORMS ARE POSSIBLE ACROSS MUCH OF THE AREA EARLY
THIS EVENING. THE MAIN THUNDERSTORM THREATS WILL BE FROM HEAVY
RAINFALL AND CLOUD TO GROUND LIGHTNING.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

NCZ036-057-069-070-182000-
IREDELL-ROWAN-LINCOLN-GASTON-
350 PM EDT FRI AUG 17 2007

...AIR QUALITY ACTION DAY IN EFFECT UNTIL 9 PM EDT THIS EVENING...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PIEDMONT 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.

   AIR QUALITY ACTION DAY.

ISOLATED THUNDERSTORMS ARE POSSIBLE ACROSS MUCH OF THE AREA EARLY
THIS EVENING. THE MAIN THUNDERSTORM THREATS WILL BE FROM HEAVY
RAINFALL AND CLOUD TO GROUND LIGHTNING.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

NCZ071-072-082-182000-
MECKLENBURG-CABARRUS-UNION NC-
350 PM EDT FRI AUG 17 2007

...AIR QUALITY ACTION DAY IN EFFECT UNTIL 9 PM EDT THIS EVENING...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PIEDMONT 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.

   AIR QUALITY ACTION DAY.

SCATTERED THUNDERSTORMS ARE POSSIBLE ACROSS MUCH OF THE SOUTHERN
PIEDMONT EARLY THIS EVENING. THE MAIN THUNDERSTORM THREATS WILL
BE FROM HEAVY RAINFALL AND CLOUD TO GROUND LIGHTNING. HOWEVER...AN
ISOLATED SEVERE THUNDERSTORM...PRODUCING HAIL TO THE SIZE OF
PENNIES AND LOCALIZED DAMAGING WIND GUSTS WILL BE POSSIBLE.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

GAZ029-SCZ009-011>014-019-182000-
ELBERT-YORK-ABBEVILLE-LAURENS-UNION SC-CHESTER-GREENWOOD-
350 PM EDT FRI AUG 17 2007

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

.DAY ONE...THIS AFTERNOON AND TONIGHT

SCATTERED THUNDERSTORMS ARE POSSIBLE ACROSS MUCH OF THE LOWER PIEDMONT
EARLY THIS EVENING. THE MAIN THUNDERSTORM THREATS WILL BE FROM
HEAVY RAINFALL AND CLOUD TO GROUND LIGHTNING. HOWEVER...AN
ISOLATED SEVERE THUNDERSTORM...PRODUCING HAIL TO THE SIZE OF
PENNIES AND LOCALIZED DAMAGING WIND GUSTS WILL BE POSSIBLE.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

LANE

In the hours before

Special weather statement, Aug 17, 4:33 PM EDT, 5 hours 33 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
433 PM EDT FRI AUG 17 2007

NCZ037-172100-
DAVIE-
433 PM EDT FRI AUG 17 2007

...A STRONG THUNDERSTORM WILL AFFECT EASTERN DAVIE COUNTY THROUGH 500
PM EDT...

AT 429 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR ADVANCE...OR 7 MILES NORTHEAST OF
MOCKSVILLE...MOVING SOUTHEAST AT 20 MPH.

* OTHER LOCATIONS AFFECTED INCLUDE BUT ARE NOT LIMITED TO FORK CHURCH
  AND ADVANCE.

SMALL HAIL...AND WIND GUSTS OF 30 TO 40 MPH ARE EXPECTED WITH THIS
STORM.
Special weather statement, Aug 17, 8:59 PM EDT, 1 hour 7 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
859 PM EDT FRI AUG 17 2007

GAZ029-180130-
ELBERT-
859 PM EDT FRI AUG 17 2007

...A STRONG THUNDERSTORM WILL AFFECT CENTRAL ELBERT COUNTY THROUGH
930 PM EDT...

AT 854 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 4 MILES NORTH OF RUCKERSVILLE...OR 8 MILES NORTH
OF ELBERTON...MOVING SOUTH AT 15 MPH.

* OTHER LOCATIONS AFFECTED INCLUDE BUT ARE NOT LIMITED TO
  RUCKERSVILLE...MIDDLETON...FORTSONIA AND ELBERTON.

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

INTENSE 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.
Special weather statement, Aug 17, 9:14 PM EDT, 52 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
914 PM EDT FRI AUG 17 2007

SCZ010-011-180145-
ABBEVILLE-ANDERSON-
914 PM EDT FRI AUG 17 2007

...A STRONG THUNDERSTORM WILL AFFECT SOUTHERN ANDERSON AND WESTERN
ABBEVILLE COUNTIES THROUGH 945 PM EDT...

AT 911 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 4 MILES NORTH OF SECESSION LAKE...OR 12 MILES
SOUTH OF ANDERSON...MOVING SOUTHWEST AT 15 MPH.

* OTHER LOCATIONS AFFECTED INCLUDE BUT ARE NOT LIMITED TO SECESSION
  LAKE...LOWNDESVILLE AND IVA.

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

INTENSE 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.
Special weather statement, Aug 17, 9:37 PM EDT, 29 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
937 PM EDT FRI AUG 17 2007

GAZ029-180200-
ELBERT-
937 PM EDT FRI AUG 17 2007

...A STRONG THUNDERSTORM WILL AFFECT WESTERN ELBERT COUNTY THROUGH
1000 PM EDT...

AT 936 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 3 MILES SOUTHWEST OF ELBERTON...MOVING SOUTH AT
20 MPH.

* OTHER LOCATIONS AFFECTED INCLUDE BUT ARE NOT LIMITED TO ELBERTON
  AND DEWY ROSE.

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

INTENSE 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.
Special weather statement, Aug 17, 10:00 PM EDT, 6 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1000 PM EDT FRI AUG 17 2007

GAZ028-SCZ004-180230-
GREATER OCONEE-HART-
1000 PM EDT FRI AUG 17 2007

...STRONG THUNDERSTORMS WILL AFFECT NORTHERN HART AND SOUTHERN OCONEE
COUNTIES THROUGH 1030 PM EDT...

AT 957 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM 3 MILES NORTH OF
FAIR PLAY TO REED CREEK...MOVING SOUTH AT 15 MPH.

* OTHER LOCATIONS AFFECTED INCLUDE BUT ARE NOT LIMITED TO REED
  CREEK...HARTWELL AND FAIR PLAY.

SMALL HAIL...AND WIND GUSTS OF 30 TO 40 MPH ARE EXPECTED WITH THESE
STORMS.

INTENSE 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.

Nearby

Severe Thunderstorm Warnings in South Carolina, 2007Every severe thunderstorm warning in 2007

Sources

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