Alert archive / Georgia / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 552, NWS Greenville-Spartanburg, SC

July 31, 2011Habersham County, Stephens County, Georgia

NWS Greenville-Spartanburg, SC issued this severe thunderstorm warning at Jul 31, 2011, 3:09 PM EDT for Habersham County, Stephens County, Georgia. It was in force for 40 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
Jul 31, 2011, 3:09 PM EDT (19:09 UTC)
Expired
Jul 31, 2011, 3:49 PM EDT
In force
40 min
Issued by
NWS Greenville-Spartanburg, SC
Area
Storm-based polygon

Counties Habersham County, GA, Stephens County, GA

The radar

The Greer radar (KGSP), 112 km from the middle of the area, began a volume at 19:12 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
Jul 31, 3:12 PM EDTTSTM WND DMG5 Ene Hollywood, GAA FEW LARGE LIMBS BLOWN DOWN WITH THE STORM NEAR AND TO THE SOUTHWEST OF TUGALO DAM.

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 3 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

Peachtre/Fal Fld, GA (KFFC), launched 12:00Z, 7.2 hours before the alert went out and 173 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 12:00Z on 2011-07-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1032 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 12:00Z on 2011-07-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 31 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
1032 J/kg
Mixed-layer CIN
-78 J/kg
Mixed-layer LCL
921 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
31 m²/s²
0-3 km storm-relative helicity
-19 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.

108 
WUUS52 KGSP 311909
SVRGSP
GAC137-257-312015-
/O.NEW.KGSP.SV.W.0552.110731T1909Z-110731T2015Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
309 PM EDT SUN JUL 31 2011

THE NATIONAL WEATHER SERVICE IN GREENVILLE-SPARTANBURG HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WESTERN STEPHENS COUNTY IN NORTHEAST GEORGIA...
  EASTERN HABERSHAM COUNTY IN NORTHEAST GEORGIA...

* UNTIL 415 PM EDT

* AT 303 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 2 MILES
  EAST OF TURNERVILLE...OR 8 MILES NORTHWEST OF TOCCOA...MOVING SOUTH
  AT 20 MPH.

* LOCATIONS IMPACTED INCLUDE...
  TOCCOA...
  BOYDVILLE AND MOUNT AIRY...
  CORNELIA...

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.

IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...CONTINUOUS LIGHTNING
IS OCCURRING WITH THIS SEVERE THUNDERSTORM. STAY INDOORS AWAY FROM
WINDOWS. AVOID USING APPLIANCES THAT REQUIRE AN ELECTRICAL CORD.
UNPLUG EXPENSIVE ELECTRONIC EQUIPMENT.

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 3474 8343 3473 8339 3465 8329 3448 8328
      3448 8354 3468 8355
TIME...MOT...LOC 1909Z 359DEG 16KT 3465 8339

$$

MCAVOY
1 follow-up statement
160 
WWUS52 KGSP 311949
SVSGSP

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
349 PM EDT SUN JUL 31 2011

GAC137-257-311959-
/O.CAN.KGSP.SV.W.0552.000000T0000Z-110731T2015Z/
STEPHENS GA-HABERSHAM GA-
349 PM EDT SUN JUL 31 2011

...THE SEVERE THUNDERSTORM WARNING FOR EASTERN HABERSHAM AND WESTERN
STEPHENS COUNTIES IS CANCELLED...

THE STORM THAT PROMPTED THE WARNING HAS DISSIPATED.

LAT...LON 3474 8343 3473 8339 3465 8329 3448 8328
      3448 8354 3468 8355
TIME...MOT...LOC 1949Z 359DEG 16KT 3447 8339

$$

MCAVOY

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 Jul 31, 2:36 PM EDT, 33 minutes earlier.

Area forecast discussion, Jul 31, 2:36 PM EDT, 33 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
236 PM EDT SUN JUL 31 2011

.SYNOPSIS...
A WEAK COLD FRONT WILL SLOWLY PUSH SOUTH ACROSS THE REGION...THEN
GRADUALLY DISSIPATE ACROSS SOUTH GEORGIA AND THE CAROLINA COAST ON
MONDAY. STRONG HIGH PRESSURE WILL BUILD OVER THE AREA TUESDAY AND
WEDNESDAY. ANOTHER WEAK COLD FRONT WILL APPROACH THE SOUTHERN
APPALACHIAN REGION LATE NEXT WEEK.

&&

.NEAR TERM /THROUGH MONDAY/...
AS UPPER TROF DIGS OFF E COAST AND RIDGE AXIS RETREATS TO CENTRAL
PLAINS...EXPECT H5 DIFLUENT FLOW OVER THE AREA THRU THIS EVE. WITH
CAPE VALUES NEAR 1000 J/KG...SFC DEW POINTS IN THE 70S...INCREASED
MOISTURE THRU THE COLUMN AND PWATS OVER 2 INCHES...EXPECT NUMEROUS
SHWRS AND TSTMS ACROSS THE CWA THRU THIS EVE. THERE IS A CHC OF
ISOLD STRONG WIND GUSTS BUT WITHOUT DRY MID LEVEL AIR THE MAIN
CONCERN WILL BE PERIODS OF HVY RAIN W/TSTMS...ESP IN AREAS THAT
PICKED UP 1-2IN OF RAIN YDA. CONVECITON WILL TAPER OFF LATE THIS EVE
AND SHOULD DIE OUT OVERNIGHT...EXCEPT A FEW LINGERING SHWRS WILL BE
PSBL IN THE S CWA. MRNG LOWS WILL COOL TO WITHIN A DEG OR TWO OF
AVG. SFC BOUNDARY PUSHES WELL S OF CWA MON WHILE NW DIFLUENT FLOW
ALOFT CONTINUES SO WE HELD ON TO SLIGHT CHC POPS ACROSS FAR S CWA
THRU EARLY AFTN. TEMPS WILL BE COOLER BUT STILL A COUPLE DEG ABOVE
AVG.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
AS OF 130 PM SUNDAY...A RATHER STRAIGHTFORWARD SHORT TERM FORECAST
IS IN THE OFFING. THE RETURN OF STRONG UPPER RIDGING AND SUBSIDENCE
WILL ENGULF THE AREA TUE AND PERSIST THROUGHOUT WED. THE OP MODELS
DISAGREE WITH THE DEGREE OF DOWNWARD FORCING AND MLVL MOISTURE
SOMEWHAT...WITH THE 12Z GFS ADDING MORE ACU THAN THE OTHER
MODELS...HOWEVER THIS WILL HAVE LITTLE IMPACT ON THE SENSIBLE WX TO
BE EXPECTED. MODEL CROSS SECTIONS SHOW TWO DISTINCT PERIODS OF
SUBSIDENCE...THE SECOND REINFORCING THE FIRST ON WED. WITH THIS IN
MIND...AND A NEBULOUS DRY SFC FLOW...MAX TEMPS SHOULD RESPOND INTO
THE U90S NON/MTNS AND L90S MTN VALLEYS TUE...AND A COUPLE DEGREES
HOTTER ON WED. A GOOD MIXING OF DRY AIR TO THE SFC WILL ALLEVIATE ANY
HEAT INDEX CONCERNS BOTH DAYS...BUT AMBIENT TEMPS WILL CREATE THE
USUAL INCREASED HEAT ISSUES...SUCH AS ENCLOSED SPACES AND PERSONAL
HYDRATION. A S/W ROUNDING THE RIDGE WILL MAKE A RUN FOR THE CWFA
LATE WED AND IT/S MOISTURE LEVELS WILL BE ENTRAINED WITH THE
PREVAILING DRY AIR...HOWEVER ISOLATED -SHRA/TSTMS ARE POSSIBLE ACROSS
THE NRN NC MTNS WED EVENING AS THIS SYSTEM NEARS.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 1210 PM SUNDAY...THE GLOBAL MODELS ARE IN GOOD AGREEMENT THAT
THE SUBTROPICAL RIDGE WILL REMAIN MORE OR LESS PARKED OVER THE
SOUTHERN PLAINS THROUGH THE MEDIUM RANGE....RESULTING IN PERSISTENT
N/NW FLOW OVER MUCH OF THE SOUTHEAST/MID-ATLANTIC. ALTHOUGH THE
MODELS ARE ALSO IN AGREEMENT THAT A WEAK FRONTAL BOUNDARY WILL SAG
INTO THE REGION BY THURSDAY...NONE ARE PARTICULARLY BULLISH ON
CONVECTIVE PRECIP THU AFTERNOON. THIS ISNT TOO SURPRISING...
CONSIDERING THAT W AND NW LOW LEVEL FLOW IN ADVANCE OF THE FRONT
PROBABLY DICTATES THAT THERE WILL NOT BE A GREAT DEAL OF MOISTURE IN
PLACE. NEVERTHELESS...ITS RARE TO SEE A SURFACE BOUNDARY MOVE OVER
THE AREA THIS TIME OF THE YEAR WITHOUT AT LEAST SCATTERED DIURNAL
CONVECTION....SO CHANCE POPS WILL BE RETAINED ACROSS MOST OF THE
AREA DURING THIS TIME. IN FACT...AT LEAST SLIGHT CHANCE DIURNAL POPS
WILL LINGER INTO NEXT WEEKEND...AS THE MODELS ARE HINTING AT ANOTHER
FRONTAL BOUNDARY DROPPING INTO THE AREA LATE IN THE PERIOD. TEMPS
WILL GENERALLY REMAIN ABOVE NORMAL...ALTHOUGH SLIGHTLY COOLER
THICKNESS VALUES MAY YIELD MAXES A LITTLE CLOSER TO CLIMO FRI AND
SAT.

&&

.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
AT KCLT AND ELSEWHERE...EXPECT SCT-NUMEROUS SHWRS/TSTMS THIS
AFTN-EVE. EXPECT TEMPO GROUPS FOR ALL TERMINALS AT SOME TIME THRU
THIS EVE FOR VRB WINDS...TSRA...LOW CIGS AND LOW VSBY. TOWARD
MIDNIGHT CONVECTION SHOULD DIMINISH...THEN LOOK FOR AREAS OF FOG
LATE TONIGHT...PREDOMINANTLY MVFR...BECMG IFR AT KAVL. AFTER EARLY
MRNG FOG LOW CLOUD CIGS LINGER THRU THE MRNG...PSBLY MVFR BUT KEPT
THAT LAYER SCT ATTM.

OUTLOOK...SFC BOUNDARY WILL PUSH S OF THE AREA MONDAY  WITH DRIER
CONDITIONS EXPECTED THRU MID WEEK...THEN INCRSNG AFTN CONVECTION AND
MRNG FOG.

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...SBK
NEAR TERM...RB
SHORT TERM...SBK
LONG TERM...JDL
AVIATION...RB
Hazardous weather outlook, Jul 31, 4:36 AM EDT, 10 hours 33 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
436 AM EDT SUN JUL 31 2011

GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065-
068>072-082-501>510-SCZ001>014-019-010845-
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-
436 AM EDT SUN JUL 31 2011

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

.DAY ONE...TODAY AND TONIGHT.

NUMEROUS THUNDERSTORMS WILL DEVELOP ACROSS THE MOUNTAINS LATE
THIS MORNING AND WILL EXPAND ACROSS THE FOOTHILLS AND PIEDMONT
THIS AFTERNOON AND EVENING. ALTHOUGH CLOUD TO GROUND LIGHTNING
AND LOCALLY HEAVY RAINFALL WILL BE THE MAIN THREATS...ONE OR TWO
OF THESE STORMS COULD PRODUCE A BRIEF PERIOD OF DAMAGING STRAIGHT
LINE WINDS. THE STORMS SHOULD DIMINISH LATE TONIGHT.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

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

In the hours before

Special weather statement, Jul 31, 2:52 PM EDT, 17 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
252 PM EDT SUN JUL 31 2011

NCZ503-505-311930-
BURKE MOUNTAINS-MCDOWELL MOUNTAINS-
252 PM EDT SUN JUL 31 2011

...A STRONG THUNDERSTORM WILL AFFECT NORTHERN MCDOWELL AND
NORTHWESTERN BURKE COUNTIES THROUGH 330 PM EDT...

AT 246 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR ASHFORD...OR 8 MILES EAST OF SPRUCE PINE...
MOVING SOUTHWEST AT 15 MPH.

SMALL HAIL...AND WIND GUSTS OF 30 TO 40 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 8183 3583 8184 3578 8192 3582 8206
      3588 8201 3587 8200 3589 8198 3591 8198
      3592 8195 3594 8196 3595 8195

MCAVOY

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 31, 3:54 PM EDTSpecial Weather StatementGSPElbert36 min

Nearby

Severe Thunderstorm Warnings in Georgia, 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.