Severe Thunderstorm Warning 358, NWS Greenville-Spartanburg, SC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
212 PM EDT TUE JUL 29 2008

.SYNOPSIS...
A WEAK TROUGH OF LOW PRESSURE WILL LINGER IN THE AREA THROUGH
WEDNESDAY. A COLD FRONT WILL APPROACH FROM THE NORTH LATE
WEDNESDAY...AND CROSS OUR AREA THURSDAY. THIS FRONT WILL STALL SOUTH
OF OUR AREA LATE FRIDAY...AND REMAIN THERE THROUGH SUNDAY. THE FRONT
WILL DISSIPATE EARLY NEXT WEEK...AND MOISTURE WILL INCREASE.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
PLENTY OF MOISTURE AND HEATING OVER CWA WITH CAPE VALUES OF
1500-2500 J/KG. WEAK H5 TROF...MTN CONVERGENCE AND LEE TROF WILL BE
MAIN TRIGGERS FOR DEEPER CONVECTION. EXPECT AT LEAST SCT SHWRS/TSTMS
THRU EARLY EVE. MODEL SOUNDINGS SHOW PWAT 1.5 INCHES OR BETTER AND
WITH RELATIVELY SLOW STEERING WINDS...PERIODS OF HEAVY RAINFALL ARE
EXPECTED. FZL OVER 15K FT AGAIN TODAY SO SIMILAR CONDITIONS AS
YESTERDAY NEEDED FOR SEVERE STORMS. DEEP CONVECTION WILL TAPER OFF
BY LATE EVE...LEAVING DEBRIS CLOUDS MOST OF THE NIGHT. TEMPS SHOULD
FALL INTO THE 60S IN THE MTNS...AROUND 70 ACROSS THE PIEDMONT. LIGHT
FOG COULD DEVELOP DURING THE PRE DAWN HOURS...ESPECIALLY IN MTN
VALLEYS.

MODELS SHOW ZONAL FLOW ALOFT WED WITH WEAK SHORTWAVES MOVG THRU
UPPER FLOW. EXPECT NO AIRMASS CHANGE WITH WEAK LEE TROF REMAINING
OVER AREA. TEMPS WARM INTO THE LOW 90S ACROSS THE PIEDMONT WITH 80S
IN THE MTNS. MODEL CAPES INCREASE IN THE AFTN AND ANOTHER ROUND OF
AFTN-EVE SHWRS/TSTMS EXPECTED ACROSS THE CWA.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
AT 2 PM EDT...AN UPPER TROUGH WILL PROGRESS TO THE EASTERN SEABOARD
BY THURSDAY...WITH A SHORTWAVE MOVING INTO ITS BASE THURSDAY
AFTERNOON. A LEE TROUGH WILL BE IN PLACE WEDNESDAY NIGHT AHEAD OF AN
APPROACHING COLD FRONT...REMAINING A FOCUS FOR EVENING CONVECTION.
THE FRONT ITSELF MOVES SOUTH ACROSS THE AREA ON THURSDAY...WITH
LITTLE MOISTURE INFLOW. UPPER LEVEL DIFFLUENCE WILL INCREASE LATE
THURSDAY TO THE SOUTH OF A JET MAX OVER THE POTOMAC VALLEY...BUT THE
BEST INSTABILITY IS SHOWS IN THE GFS TO BE SOUTHEAST OF OUR AREA.
CHANCE POPS WILL BE CARRIED IN THE FORECAST...TRENDING FROM LOWER IN
THE NORTH TO HIGHER IN THE SOUTH.

THE FRONT CONTINUES SOUTH ON THURSDAY NIGHT AND FRIDAY...WITH BETTER
INSTABILITY REMAINING SOUTH OF OUR AREA. A DOWNWARD TREND IN POPS
WILL RESULT...ESPECIALLY IN THE NORTHERN TIER OF OUR AREA.
TEMPERATURES WILL REMAIN WARM ON THURSDAY IN ADVANCE OF THE
FRONT...AS THE LEE TROUGH PROVIDES A DOWNSLOPE FLOW COMPONENT EAST
OF THE MOUNTAINS. DOWNSLOPE FLOW CONTINUES BEHIND THE FRONTAL
PASSAGE ON FRIDAY... OFFSETTING WEAK COLD ADVECTION AND UPPER LEVEL
HEIGHT FALLS TO PRODUCE ANOTHER WARM DAY.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AT 1 PM EDT...THE ECMWF AND GFS SHOW A LONGWAVE TROUGH ALONG THE
EAST COAST ON SATURDAY. THE NORTHERN PORTION OF THIS TROUGH
PROGRESSES INTO THE ATLANTIC ON SUNDAY...WHILE THE SOUTHERN PORTION
REMAINS OVER NORTH FL. BY MONDAY AN UPPER RIDGE BECOMES CENTERED
OVER THE OH VALLEY...WHILE THE SOUTHERN STREAM PORTION OF THE FL
TROUGH RETROGRESSES ACROSS THE NORTHERN GULF. BY TUESDAY THE HIGH IS
CENTERED OFF THE VA CAPES.

A COLD FRONT WILL ALREADY BE SOUTH OF OUR AREA ON SATURDAY...
BECOMING STATIONARY SOUTH OF INTERSTATE 20 ON SUNDAY. THIS FRONT
DISSIPATES ON MONDAY...LEAVING OUR AREA IN A WARM SUBTROPICAL AIR
MASS THROUGH TUESDAY...WITH THE NEAREST FRONT NORTH OF THE OH RIVER.
SOMEWHAT DRIER AND COOLER CONDITIONS BEHIND THE FRONT OVER THE
WEEKEND WILL MODIFY AS HEAT AND HUMIDITY INCREASE EARLY NEXT WEEK.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AT LEAST SCT TSTMS EXPECTED TO DEVELOP IN UNSTABLE AIRMASS THIS
AFTN...ESP W CWA AND OVER MTNS. HAVE CB ALL TAFS AFT 19Z AND VCTS AT
ALL BUT KCLT WHICH LIES IN SLIGHTLY MORE STABLE AIR. SW WINDS 6-8KTS
SHOULD CONTINUE THRU SUNSET...TAPERING OFF OVERNIGHT WITH SCT LOW
CLOUDS AND SCT-BKN MID CLOUDS. MVFR FOG LIKELY EARLY WED MRNG...WITH
IFR FOG KAVL 11-14Z.

OUTLOOK...WEAK UPPER LEVEL DISTURBANCES MAY TRIGGER AFTN-EVE
TSTMS...ESP AS A COLD FRONT DROPS S TOWARD THE CWA WED-THU WITH
CHANCE SHWRS/TSTMS EACH DAY. FOG EXPECTED EACH MORNING. DRYER HIGH
PRESSURE SHOULD START BUILDING IN FROM THE N FRI.

&&

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

&&

SYNOPSIS...JAT
NEAR TERM...RB
SHORT TERM...JAT
LONG TERM...JAT
AVIATION...RB

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
249 PM EDT TUE JUL 29 2008

GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065-
068>072-082-501>510-SCZ001>014-019-301900-
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-
249 PM EDT TUE JUL 29 2008

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

.DAY ONE...THIS AFTERNOON AND TONIGHT.

SCATTERED TO NUMEROUS THUNDERSTORMS WILL MOVE EAST ACROSS THE
CAROLINAS AND NORTHEAST GEORGIA THIS AFTERNOON AND EVENING.
SEVERAL OF THESE STORMS COULD BE CAPABLE OF PRODUCE DAMAGING
WINDS...LARGE HAIL...TORRENTIAL RAIN AND FREQUENT LIGHTNING.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY.

SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS ARE EXPECTED
WEDNESDAY AND THURSDAY...PRIMARILY DURING THE AFTERNOON AND
EVENING HOURS. SOME OF THESE STORMS COULD BECOME SEVERE
...PARTICULARLY ON THURSDAY...PRODUCING LARGE HAIL AND DAMAGING
WIND.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED.

07

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
134 PM EDT TUE JUL 29 2008

GAZ010-017-018-SCZ001-291800-
HABERSHAM-OCONEE MOUNTAINS-RABUN-STEPHENS-
134 PM EDT TUE JUL 29 2008

...A STRONG THUNDERSTORM WILL AFFECT EASTERN HABERSHAM...NORTHERN
STEPHENS...SOUTHERN RABUN AND WESTERN OCONEE COUNTIES THROUGH 200 PM
EDT...

AT 130 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR TALLULAH FALLS...OR 9 MILES NORTH OF
TOCCOA...MOVING EAST AT 11 MPH.

* OTHER LOCATIONS AFFECTED INCLUDE BUT ARE NOT LIMITED TO LAKE
  RABUN...TURNERVILLE...TALLULAH FALLS...LAKEMONT...HOLLYWOOD AND
  LONG CREEK.

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

RB

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
225 PM EDT TUE JUL 29 2008

GAZ010-SCZ001-291915-
OCONEE MOUNTAINS-RABUN-
225 PM EDT TUE JUL 29 2008

...A STRONG THUNDERSTORM WILL AFFECT CENTRAL OCONEE AND NORTHEASTERN
RABUN COUNTIES THROUGH 315 PM EDT...

AT 225 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 4 MILES EAST OF PINE MOUNTAIN...OR 11 MILES NORTH
OF WALHALLA...MOVING SOUTH AT 4 MPH.

THIS STORM WILL BE NEAR...
  MOUNTAIN REST BY 315 PM EDT.

PEA 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.

BSH

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
245 PM EDT TUE JUL 29 2008

NCZ064-065-SCZ002-003-006-291930-
GREATER GREENVILLE-GREENVILLE MOUNTAINS-HENDERSON-PICKENS
MOUNTAINS-TRANSYLVANIA-
245 PM EDT TUE JUL 29 2008

...A STRONG THUNDERSTORM WILL AFFECT EASTERN TRANSYLVANIA...
NORTHEASTERN PICKENS...NORTHWESTERN GREENVILLE AND SOUTHERN HENDERSON
COUNTIES THROUGH 330 PM EDT...

AT 245 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR CAESARS HEAD...OR 10 MILES SOUTHEAST OF
BREVARD...MOVING SOUTHEAST AT 4 MPH.

THIS STORM WILL BE NEAR...
  CAESARS HEAD BY 255 PM EDT.
  JONES GAP STATE PARK BY 310 PM EDT.
  6 MILES NORTHWEST OF MARIETTA BY 330 PM EDT.

PEA 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.

BSH

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
321 PM EDT TUE JUL 29 2008

NCZ064-292000-
TRANSYLVANIA-
321 PM EDT TUE JUL 29 2008

...A STRONG THUNDERSTORM WILL AFFECT EASTERN TRANSYLVANIA COUNTY
THROUGH 400 PM EDT...

AT 320 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 3 MILES SOUTH OF BREVARD. THIS STORM WAS NEARLY
STATIONARY.

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

BSH

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
328 PM EDT TUE JUL 29 2008

NCZ056-502-504-292015-
CATAWBA-GREATER BURKE-GREATER CALDWELL-
328 PM EDT TUE JUL 29 2008

...A STRONG THUNDERSTORM WILL AFFECT EASTERN BURKE...SOUTHERN
CALDWELL AND SOUTHWESTERN CATAWBA COUNTIES THROUGH 415 PM EDT...

AT 328 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 4 MILES NORTHEAST OF MORGANTON...MOVING SOUTHEAST
AT 13 MPH.

THIS STORM WILL BE NEAR...
  5 MILES SOUTHWEST OF LAKE RHODHISS BY 340 PM EDT.
  VALDESE BY 345 PM EDT.
  RUTHERFORD COLLEGE BY 350 PM EDT.
  5 MILES SOUTHWEST OF CONNELLY SPRINGS BY 355 PM EDT.
  5 MILES SOUTHWEST OF ICARD BY 405 PM EDT.

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

BSH