Severe Thunderstorm Warning 225, NWS Greenville-Spartanburg, SC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
256 PM EDT THU MAY 25 2006

.SHORT TERM /TONIGHT THROUGH SUNDAY/...
SHORTWAVE ENERGY ROUNDING THE GREAT LAKES UPPER LOW WILL CROSS THE
AREA OVER THE NEXT 24 HOURS. SCATTERED CONVECTION ASSOCIATED WITH A
DAMPENING SHORTWAVE IN TENNESSEE WILL CROSS THE AREA THROUGH MID
EVENING...AND THEN MOVE EAST OF THE AREA. INSTABILITY EXPECTED TO BE
SUFFICIENT TO SUPPORT SEVERE WEATHER INTO THE PIEDMONT COUNTIES
EARLY THIS EVENING. A RELATIVE LULL IS EXPECTED OVERNIGHT IN THE
WAKE OF THE FIRST SYSTEM...WITH LOW LEVEL FLOW BRINGING ADDITIONAL
MOISTURE FROM THE GULF LATE TONIGHT AS THE REMAINS OF A COLD FRONT
APPROACH FROM THE WEST. THIS SYSTEM IS EXPECTED TO REACH THE
MOUNTAINS BY EARLY FRIDAY MORNING...WHILE THE UPPER LOW OPENS AS IT
EXITS THE GREAT LAKES...AND THE REMAINING TORUGH AMPLIFIES OVER THE
SOUTHERN APPALACHIANS. INSTABILITY IS EXPECTED TO BE EVEN BETTER
THAN TODAY...WITH STRONGER WINDS ALOFT...AND NO DRY AXIS IN THE
MOUNTAINS AS EXISTED THIS MORNING. CHANCE POPS WILL AGAIN BE
CARRIED...WITH HIGH CHANCE POPS IN THE NORTHERN PORTION OF THE
AREA NEAREST THE THE UPPER SYSTEM AND WHERE UPPER DIVERGENCE IS
BEST. TEMPERATURES WILL BE RATHER WARM FRIDAY DESPITE LOWERING
HEIGHTS AS THE WIND WILL HAVE A SLIGHT WESTERLY DOWNSLOPE
COMPONENT. -JAT

THE AXIS OF THE VORT LOBE AT THE BOTTOM OF THE TROF SHOULD PUSH
EAST ACROSS THE FORECAST AREA FRIDAY EVENING...WITH THE FORCING
FOR CONVECTION MOVING OFF TO THE EAST BY MIDNIGHT. A CHANCE POP
WILL BE CARRIED THROUGH THE EVENING...THEN TAPERING OFF TO A SMALL
CHANCE OVER THE MOUNTAINS THROUGH THE EARLY MORNING HOURS AS A NW
UPSLOPE FLOW DEVELOPS IN THE WAKE OF THE TROF.

SATURDAY AND SUNDAY SHOULD BE RELATIVELY QUIET AS A LARGE UPPER
ANTICYCLONE BUILDS OVER THE SRN APPALACHIANS AND TN VALLEY WITH
WEAK HIGH PRESSURE AT THE SURFACE. THIS SHOULD BRING SLIGHTLY
WARMER TEMPS BOTH DAYS...PROBABLY WITH THE FIRST 90 DEGREE HIGHS
OF THE SEASON IN SOME LOCATIONS EAST OF THE MOUNTAINS. -PM

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
THE MEDIUM RANGE PERIOD LOOKS RATHER PERSISTENT WITH A BROAD AND
WEAK UPPER LOW SPINNING SOMEWHERE OFF THE SOUTHEAST COAST AND A HIGH
AMPLITUDE RIDGE OVER THE MS/OH VALLEY AND GREAT LAKES...WITH THE
WESTERN CAROLINAS STUCK SOMEWHERE IN BETWEEN. FOR MONDAY AT LEAST...
THE UPPER RIDGE SHOULD BE LOCATED FAR ENOUGH EAST TO KEEP US DRY.
HOWEVER...THESE FEATURES RETROGRADE SOMEWHAT DURING THE EARLY PART
OF THE WEEK. THE MODELS SHOW MOISTURE ON THE WEST SIDE OF THE
MOUNTAINS AND CLOSER TO THE UPPER LOW CIRCULATION ON TUESDAY AND
WEDNESDAY...WITH RELATIVELY DRIER AIR OVER THE PIEDMONT. THIS FAVORS
DIURNAL CONVECTION FORCED BY DIFFERENTIAL HEATING OVER THE
MOUNTAINS...BUT A DRY FORECAST FROM THE FOOTHILLS AND EAST. SOME
ATLANTIC MOISTURE MOVES FARTHER WEST ON THURSDAY WHICH SHOULD ALLOW
FOR THE POSSIBILITY OF CONVECTION EVERYWHERE. HAVE FOLLOWED A BLEND
OF HPC AND MEX GUIDANCE FOR TEMPS THROUGHOUT.

&&

.AVIATION...
THE BAND OF CONVECTION IS ALREADY MOVING OUT OF THE MOUNTAINS AND
INTO THE FOOTHILLS AND PIEDMONT AT 17Z. THUNDER...GUSTY WIND...
VISIBILITY OF 1 OR 2 MILES...AND MVFR CEILINGS WILL BE CARRIED
EARLY AT KGSP AND KGMU...WHILE THE SHOWERS NOW AT KAVL WILL BE
ALLOWED TO DIMINISH. CUMULONIMBUS WITH A LOW VFR CEILING WILL BE
CARRIED AT KAND...KHKY...AND KCLT LATE THIS AFTERNOON.

BY MID EVENING THE LOW LEVELS ARE EXPECTED TO BECOME SCATTERED.
ALTHOUGH MODEL TIME HEIGHTS VARY ON UPPER LEVEL MOISTURE...A CIRRUS
CEILING WILL BE CARRIED TO ACCOUNT FOR A SECOND ROUND OF CONVECTION
ASSOCIATED WITH ANOTHER SHORTWAVE FARTHER UPSTREAM. THE WIND SHOULD
STAY UP AT 3 TO 6 KNOTS OUT OF THE SOUTHWEST OVERNIGHT IN A WEAK
GRADIENT TO THE SOUTH OF A GREAT LAKES SURFACE LOW. AREAS THAT
RECEIVE RAINFALL LATE THIS AFTERNOON AND DECOUPLE...WILL PROBABLY
ENCOUNTER MVFR FOG LATE TONIGHT. AT THIS POINT THE BEST CANDIDATES
FOR RAINFALL ARE KAVL AND KHKY...WHILE THE BEST CANDIDATE FOR LIGHT
WINDS IS KAND.

THE WIND IS EXPECTED TO INCREASE FROM THE WEST SOUTHWEST FRIDAY
MORNING AS MIXING OCCURS. THE NEXT INCREASE IN LOW LEVEL MOISTURE
WILL REACH THE MOUNTAINS BY DAYBREAK...AND WITH UPVALLEY FLOW...KAVL
IS EXPECTED TO DEVELOP ANOTHER LOW VFR CEILING. CEILINGS ARE NOT
EXPECTED IN THE LEE OF THE MOUNTAINS UNTIL AFTERNOON HEATING
INCREASES CUMULUS COVERAGE.

&&

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

SHORT TERM...JAT/PM
LONG TERM...MOORE
AVIATION...JAT

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
630 AM EDT THU MAY 25 2006

GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065-
068>072-082-501>510-SCZ001>014-019-261030-
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-
630 AM EDT THU MAY 25 2006

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

.DAY ONE...TODAY AND TONIGHT

SCATTERED THUNDERSTORMS WILL BE DEVELOPING ACROSS THE REGION TODAY.
A COUPLE OF THESE STORMS MAY BE SEVERE THIS AFTERNOON AND EVENING...
PRODUCING LARGE HAIL AND/OR DAMAGING WIND GUSTS.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

THUNDERSTORMS WILL BE POSSIBLE AGAIN ON FRIDAY. SOME SEVERE STORMS
MAY DEVELOP AS WELL.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED TODAY AND/OR FRIDAY.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
232 PM EDT THU MAY 25 2006

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

0225 PM     HAIL             SIX MILE                34.81N 82.82W
05/25/2006  E0.75 INCH       PICKENS            SC   POST OFFICE

&&

DEO

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
238 PM EDT THU MAY 25 2006

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

0215 PM     TSTM WND DMG     SPARTANBURG             34.94N 81.93W
05/25/2006                   SPARTANBURG        SC   AMATEUR RADIO

            HAM RADIO OPERATOR REPORTED TREES DOWN AT HERON CIRCLE
            AND BUSINESS 85. FUNNEL CLOUD ALSO REPORTED.

&&

DEO

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
242 PM EDT THU MAY 25 2006

NCZ068-SCZ008-009-013-251945-
CHEROKEE-CLEVELAND-UNION-YORK-
242 PM EDT THU MAY 25 2006

...STRONG THUNDERSTORMS WERE AFFECTING CHEROKEE...CLEVELAND...UNION
AND YORK COUNTIES...

AT 235 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM COWPENS TO PACOLET
TO 6 MILES EAST OF WOODRUFF...MOVING EAST AT 20 MPH.

THESE STORMS WILL BE NEAR...
  THICKETTY BY 250 PM EDT.
  GAFFNEY BY 300 PM EDT.
  JONESVILLE BY 305 PM EDT.
  BLACKSBURG BY 325 PM EDT.
  HICKORY GROVE BY 330 PM EDT.
  LOCKHART BY 345 PM EDT.

PEA SIZE HAIL...AND WINDS AROUND 50 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.

44

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
253 PM EDT THU MAY 25 2006

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

0205 PM     TSTM WND DMG     WALHALLA                34.77N 83.06W
05/25/2006                   OCONEE             SC   FIRE DEPT/RESCUE

            TREE DOWN ON A HOUSE ON HUGHES LANE...AND A TREE FELL
            ONTO A POWER LINE ON CHURCH STREET.

&&

44

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
258 PM EDT THU MAY 25 2006

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

0212 PM     HAIL             WESTMINSTER             34.67N 83.09W
05/25/2006  E0.75 INCH       OCONEE             SC   FIRE DEPT/RESCUE

            LOTS OF PEA-SIZED TO DIME-SIZED HAIL FELL IN THREE
            DIFFERENT PHASES OF THE STORM.

0212 PM     TSTM WND DMG     WESTMINSTER             34.67N 83.09W
05/25/2006                   OCONEE             SC   FIRE DEPT/RESCUE

            TREES DOWN ON ENGLAND STREET...DEBRA DRIVE AND
            WESTMINSTER HIGHWAY.

&&

44

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
314 PM EDT THU MAY 25 2006

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

0310 PM     HAIL             TOCCOA                  34.58N 83.32W
05/25/2006  E0.75 INCH       STEPHENS           GA   TRAINED SPOTTER

&&

44