Severe Thunderstorm Warning 217, NWS Greenville-Spartanburg, SC

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
323 PM EDT THU AUG 18 2005

.SHORT TERM (TONIGHT THROUGH SUNDAY)...
AFTER REVIEWING UPSTREAM CONVECTION...ANTECEDENT RAINFALL OVER THE
PAST 24 HOURS...AND CURRENT FFG DATA...WILL EXTEND EXISTING FLASH
FLOOD WATCH UNTIL MIDNIGHT...AND EXPAND TO MADISON COUNTY.

H5 SHORTWAVE EXPECTED TO CROSS THE CURRENT WATCH AREA THROUGH THE
EVENING HOURS. THE NAM DEPICTS A SECONDARY SHORTWAVE TOWARD DAYBREAK
FRIDAY...WHILE THE GFS IS MUCH MORE MUTED AS 500 MB HEIGHTS BEGIN TO
RISE. ATHOUGH 850 MB FLOW BECOMES INCREASINGLY WESTERLY
OVERNIGHT...THIS IS ACTUALLY A WARM ADVECTION PATTERN INTO THE HIGH
TERRAIN. THE FOOTHILL AND PIEDMONT SHALLOW COLD WEDGE SHOULD BECOME
INCREASINGLY SQUEEZED TONIGHT AND THEN ERODE FAIRLY QUICKLY EARLY
FRIDAY.

EARLY PART OF PACKAGE FEATURES UPPER RIDGE AMPLIFYING OVER AL
FRI...RAISING HEIGHTS OVER MUCH OF SE USA. WILL LIMIT TEMPERATURE
GAIN FRI TO JUST BELOW GUIDANCE...IN LINGERING
MOISTURE/CLOUDS/PRECIP. MINIMUM TEMPERATURES RATHER WARM IN HUMID
AIR MASS UNDER CLOUD COVER. POPS MUCH LOWER FRI THAN TODAY AS LOW
LEVEL FLOW LOSES MUCH OF ITS UPSLOPE COMPONENT AND MID LEVELS DRY.
EXPECT WARMING SAT AS AREA GETS ON BACK SIDE OF SURFACE RIDGE AND
BEST MOISTURE ON PERIPHERY OF RIDGE MIGRATES TO GULF AND ATLANTIC
COASTS...BUT WENT TOWARD LOWER END OF GUIDANCE WITH MAX TEMPERATURE
AS SOME MOISTURE AND CLOUDS LINGER. POPS EVEN LOWER SAT THAN FRI AS
LOW LEVEL MOISTURE DECREASES AND UPPER ENERGY REMAINS TO N. BY LATE
SAT...UPPER TROUGH BEGINS TO AMPIFY OVER OH/TN VALLEYS...AS COLD
FRONT DIVES SE TOWARD AREA. WELL DEFINED FROPA EXPECTED SUN...WITH
CLOUDS/PRECIP COOLING AREA SLIGHTLY IN ADVANCE OF BETTER COLD
ADVECTION. REDUCED POPS WITH FRONT SUN IN WESTERLY LOW LEVEL FLOW
AHEAD OF BOUNDARY.

&&

.LONG TERM (SUNDAY NIGHT THROUGH THURSDAY)...
EXTENDED FORECAST STARTS MON WITH UPPER TROUGH AMPLIFYING ALONG E
COAST...STATIONARY FRONT ALONG COAST OF SE USA...AND COOL SURFACE
RIDGE ENTRENCHED OVER AREA. SMALL POPS THROUGHOUT EXTENDED...WITH BEST
MOISTURE/POPS E PORTION OF AREA...ALTHOUGH UPPER IMPULSES MOVING
DOWN BACK SIDE OF TROUGH MAY KEEP SOME MOISTURE IN NC MTS.
TEMPERATURES TO REMAIN COOL...EVEN AT END OF PERIOD WHEN UPPER
RIDGE BEGINS TO BUILD OVER AREA...AS SURFACE FLOW REMAINS NE WITH
RIDGE ALONG EASTERN SEABOARD...AND CLOUD COVER SHIFTS FROM E PORTION TO
S PORTION AND INCREASES AHEAD OF NEXT FRONT.

&&

.AVIATION...
WIDESPREAD SHOWERS ASSOCIATED WITH PASSING SHORTWAVE WILL MAINLY
AFFECT TAF LOCATIONS FROM KHKY TO KCLT THROUGH THE LATE AFTERNOON.
BREAKS IN LOW CLOUDS ARE ALSO INCREASING CONVECTIVE CHANCES FROM THE
SOUTHWEST THIS AFTERNOON...WITH AT LEAST VICINITY THUNDER LIKELY
FROM KAVL TO KGSP BY 21Z...AND KAND SHORTLY THEREAFTER. WITH WEAK
WEDGE FRONT BECOMING INCREASINGLY PINCHED...ONLY KHKY SHOULD REMAIN
ENTRENCHED IN NE FLOW THROUGH THE EVENING. WESTERLY FLOW OVER THE
MTNS SHOULD FINISH WEDGE LATE TONIGHT...BUT SHALLOW MOISTURE WILL
CONTRIBUTE TO MVFR TO IFR VSBY AND CIG BEFORE DAYBREAK. CONDITIONS
WILL STEADILY IMPROVE DURING THE OUTLOOK PERIOD WITH NW FLOW AND
SLIGHT DRYING ALOFT.

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...FLASH FLOOD WATCH FOR NCZ033-034-048-049-050-054-055 UNTIL
     MIDNIGHT TONIGHT.
SC...NONE.
&&

SHORT TERM...HG/JAT
LONG TERM...JAT
AVIATION...HG

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
652 AM EDT THU AUG 18 2005

GAZ010-017-018-026-028-029-NCZ033>037-048>059-062>072-082-
SCZ001>014-019-191100-
RABUN-HABERSHAM-STEPHENS-FRANKLIN-HART-ELBERT-AVERY-CALDWELL-
ALEXANDER-IREDELL-DAVIE-MADISON-YANCEY-MITCHELL-SWAIN-HAYWOOD-
BUNCOMBE-MCDOWELL-BURKE-CATAWBA-ROWAN-GRAHAM-NORTHERN JACKSON-
MACON-SOUTHERN JACKSON-TRANSYLVANIA-HENDERSON-POLK-RUTHERFORD-
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-
652 AM EDT THU AUG 18 2005

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

.DAY ONE...TODAY AND TONIGHT

WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY INTO
THIS EVENING. LOCALLY HEAVY RAIN IS THE BIGGEST THREAT FROM
STORMS TODAY AND ISOLATED EXCESSIVE RAINFALL IS POSSIBLE...
ESPECIALLY OVER PARTS OF NORTHWEST NORTH CAROLINA WHERE A
FLASH FLOOD WATCH IS IN EFFECT. FOR FURTHER DETAILS...PLEASE
SEE THE LATEST FFAGSP...ISSUED BY THIS OFFICE.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

ISOLATED TO SCATTERED THUNDERSTORMS ARE EXPECTED EACH AFTERNOON
AND EVENING FRIDAY THROUGH SUNDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
727 PM EDT THU AUG 18 2005

GAZ010-017-018-026-028-029-SCZ001-004-005-010-011-019-190030-
ABBEVILLE-ANDERSON-ELBERT-FRANKLIN GA-GREATER OCONEE-GREATER PICKENS-
GREENWOOD-HABERSHAM-HART-OCONEE MOUNTAINS-RABUN-STEPHENS-
INCLUDING THE CITIES OF...ABBEVILLE...ANDERSON...CLARKESVILLE...
CLAYTON...ELBERTON...GREENWOOD...HARTWELL...TOCCOA
727 PM EDT THU AUG 18 2005

...STRONG THUNDERSTORM POTENTIAL IN NORTHEAST GEORGIA AND THE
WESTERN UPSTATE OF SOUTH CAROLINA...

AT 718 PM EDT...A LARGE AREA OF THUNDERSTORMS...SOME WITH FREQUENT
CLOUD TO GROUND LIGHTNING...ARE MOVING EAST SOUTHEAST AT 15 MPH
ACROSS EXTREME NORTH GEORGIA.  MOST OF THE STORMS EXTENDED FROM SKY
VALLEY...WESTWARD TOWARD BLAIRSVILLE AND LOCATIONS FARTHER WEST IN
FAR NORTH GEORGIA.  WITH VERY UNSTABLE AIR ACROSS NORTHEAST GEORGIA
AND PORTIONS OF THE FAR WESTERN UPSTATE...THERE IS THE POTENTIAL
FOR SOME OF THESE STORMS TO PRODUCE STRONG WIND GUSTS OF OVER 40 MPH
AND HAIL.

THERE IS ALSO THE POTENTIAL FOR RAINFALL OF WELL OVER AN INCH IN
AN HOUR...ESPECIALLY WHERE STORMS WITH HEAVY RAIN REPEAT OVER THE
SAME LOCATIONS.  THIS COULD LEAD TO FLOODING OF LOW LYING AREAS...
ESPECIALLY THOSE THAT ARE FLOOD PRONE.

OUTLAW

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
844 PM EDT THU AUG 18 2005

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

0835 PM     TSTM WND DMG     CLARKESVILLE            34.61N 83.52W
08/18/2005                   HABERSHAM          GA   EMERGENCY MNGR

            NUMEROUS TREES AND POWER LINES DOWN FROM HIGHWAY 115 JUST
            WEST OF CLAREKSVILLE TO BRYSON ROAD IN THE NORTHEAST PART
            OF THE COUNTY. TO THE SOUTH...AN EXPLOSION AT A POWER
            PLANT HAS RESULTED IN THE LOSS OF POWER FROM DEMOREST TO
            CORNELIA AND MOUNT AIRY. UNCLEAR YET WHAT CAUSED THE
            EXPLOSION AT THE POWER PLANT.

&&

BURRUS

PRELIMINARY LOCAL STORM REPORT...CORRECTED FOR TYPO
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
844 PM EDT THU AUG 18 2005

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

0835 PM     TSTM WND DMG     CLARKESVILLE            34.61N 83.52W
08/18/2005                   HABERSHAM          GA   EMERGENCY MNGR

            NUMEROUS TREES AND POWER LINES DOWN FROM HIGHWAY 115 JUST
            WEST OF CLARKESVILLE TO BRYSON ROAD IN THE NORTHEAST PART
            OF THE COUNTY. TO THE SOUTH...AN EXPLOSION AT A POWER
            PLANT HAS RESULTED IN THE LOSS OF POWER FROM DEMOREST TO
            CORNELIA AND MOUNT AIRY. UNCLEAR YET WHAT CAUSED THE
            EXPLOSION AT THE POWER PLANT.

&&

BURRUS