Severe Thunderstorm Warning 150, NWS Greenville-Spartanburg, SC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
230 PM EDT WED JUL 14 2004

.SHORT TERM (TONIGHT THROUGH SATURDAY)...
SURFACE FRONT HAS INCREASINGLY BECOME ZONALLY ORIENTED OVER TN THIS
AFTERNOON...WITH A PUSH ACROSS THE WESTERN CAROLINAS EXPECTED BY
EARLY EVENING. AIRMASS REMAINS MODERATELY UNSTABLE THIS AFTERNOON
WITH 2000+ CAPES ACROSS THE PIEDMONT...HOWEVER SECTIONS UNDER MCS
DEBRIS CLOUDS FOR MUCH OF THE DAY SHOW CONSIDERABLY LESS INSTABILITY.
WEST TO NW FLOW CONT TO MIX OUT DEWPOINTS IN MANY LOCATIONS TO LIMIT
CAPE AS WELL. VAD WIND PROFILE SHOWS INCREASING SHEAR PROFILE WITH
NEARLY 40 KT OF FLOW AROUND 3 KM. COVERAGE HAS BEEN VERY MINIMAL
TODAY...BUT POTENTIAL STILL EXISTS THROUGH EVENING FOR SCATTERED
COVERAGE AND ISOLATED SEVERE GIVEN FAVORABLE WIND SHEAR.

MM5 MODEL CROSS SECTIONS ALSO STILL FEATURE STRONG SUBSIDENCE WITH
THE FRONT THIS EVENING WITH ISENTROPIC SURFACES DIPPING TOWARD THE
GROUND. WINDS HAVE YET TO COME UP IN MOST LOCATIONS OUTSIDE THE
MOUNTAINS...BUT BETTER PUSH SHOULD COME CLOSER TO 21Z. WILL THUS
KEEP LAKE WIND ADVISORY CRITERIA WINDS GOING INTO THE EVENING HOURS.

SFC FRONT PUSHES JUST SOUTH OF THE AREA THROUGH THU...WITH TRANSIENT
UPPER SHORTWAVES ROTATING INTO THE REGION ON THE BACK SIDE OF THE
DEEP UPPER LOW OVER NEW ENGLAND. CONTINENTAL MOISTURE WITH EACH
WEAK SYSTEM LOOKS SPARSE SO NO POPS ARE EXPECTED. THE STALLED FRONT
MAY RETREAT SLIGHTLY NORTHWARD INTO THE WEEKEND...WITH WEAK WAVES
OF LOW PRES POSSIBLY DEVELOPING FROM THE SRN PLAINS TO THE LOWER MS
VALLEY AND TRACKING EASTWARD. ONLY ISOLATED DIURNAL CONVECTIVE
CHANCES IN WESTERN SECTIONS WILL BE POSSIBLE PM SATURDAY.
&&

.LONG TERM (SATURDAY NIGHT THROUGH WEDNESDAY)...
EASTERN U.S. UPPER TROUGH STILL FORECAST TO BE IN PLACE AT THE START
OF THE EXTENDED PERIOD WITH MEAN TROUGHING STILL PRESENT EVEN AT THE
END OF DAY 7. DIFFICULT TO TIME PERIODIC S/WV ENERGY ROTATING THROUGH
THE L/WV...SO WILL CONTINUE TO FOCUS BEST CHANCE FOR SHOWERS ON
SUNDAY...OUT AHEAD OF AND COINCIDENT WITH COLD FRONTAL PASSAGE.
LITTLE CHANGE TO GOING TEMPS WITH THE MEAN NUMBERS SLIGHTLY BELOW
NORMAL...ESPECIALLY THROUGH THE FIRST HALF OF THE PERIOD WHEN
TROUGH IS DEEPEST.
&&

.AVIATION...
HAVE CONTINUED TREND OF GUSTY WESTERLY SFC WINDS AT ALL TAF SITES
THIS AFTERNOON WITH INCREASED MIXING AHEAD OF APPROACHING COLD
FRONT.  ANY RENEWED DEEP CONVECTIVE TRENDS CONTINUE TO BE UNCERTAIN
WITH SOME SUPPRESSION ATTM IN THE WAKE OF NOW DISSIPATED MCS COMBINED
WITH SOME DOWNSLOPE AIDED LOW SFC DWPTS. FOR NOW...HAVE GONE FOR A
PERIOD OF JUST VCTS AT ALL SITES FROM 21Z-01Z. OTHERWISE...VEERED
WINDS TO NW TONIGHT BEHIND FRONT AND KEPT WINDS UP ALL NIGHT WITH
SOME WEAK TO MODERATE PRESSURE RISES. SKY AND VSBY TONIGHT AND
THURSDAY MORNING SHOULD REMAIN IN VFR CATEGORY.

&&

.GSP WATCHES/WARNINGS/ADVISORIES...
GA...LAKE WIND ADVISORY FOR ZONES GAZ010-017-018-026-028-029 UNTIL 8
     PM EDT.
NC...LAKE WIND ADVISORY FOR ZONES NCZ033>035-037-038-048>059-
     062>072-082 UNTIL 8 PM EDT.
SC...LAKE WIND ADVISORY FOR ZONES SCZ001>014-019 UNTIL 8 PM EDT.
&&

SHORT TERM...HG
LONG TERM...CSH
AVIATION...CSH

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
439 AM EDT WED JUL 14 2004

GAZ010-017-018-026-028-029-NCZ033>037-048>059-062>072-082-SCZ001>014-
019-150845-
ABBEVILLE SC-ALEXANDER NC-ANDERSON SC-AVERY NC-BUNCOMBE NC-BURKE NC-
CABARRUS NC-CALDWELL NC-CATAWBA NC-CHEROKEE SC-CHESTER SC-
CLEVELAND NC-DAVIE NC-ELBERT GA-FRANKLIN GA-GASTON NC-GRAHAM NC-
GREATER GREENVILLE SC-GREATER OCONEE SC-GREATER PICKENS SC-
GREENVILLE MOUNTAINS SC-GREENWOOD SC-HABERSHAM GA-HART GA-HAYWOOD NC-
HENDERSON NC-IREDELL NC-LAURENS SC-LINCOLN NC-MACON NC-MADISON NC-
MCDOWELL NC-MECKLENBURG NC-MITCHELL NC-NORTHERN JACKSON NC-
OCONEE MOUNTAINS SC-PICKENS MOUNTAINS SC-POLK NC-RABUN GA-ROWAN NC-
RUTHERFORD NC-SOUTHERN JACKSON NC-SPARTANBURG SC-STEPHENS GA-
SWAIN NC-TRANSYLVANIA NC-UNION SC-UNION NC-YANCEY NC-YORK SC-
439 AM EDT WED JUL 14 2004

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

.DAY ONE...
THERE IS A CHANCE OF THUNDERSTORMS TODAY. DUE TO AN APPROACHING UPPER
TROF AND A SURFACE COLD FRONT...THE ATMOSPHERE IS EXPECTED TO BECOME
VERY UNSTABLE BY THIS AFTERNOON. DAMAGING WINDS...LARGE HAIL AND
HEAVY RAIN ARE POSSIBLE...ESPECIALLY OVER THE MOUNTAINS THIS
AFTERNOON AND EARLY EVENING.

.DAYS TWO THROUGH SEVEN...
THERE IS A CHANCE OF THUNDERSTORMS ON SUNDAY. SOME STORMS MAY CONTAIN
LARGE HAIL...DAMAGING WINDS AND HEAVY RAIN.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED.

RB

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1122 AM EDT WED JUL 14 2004

NCZ034>037-051-056>058-142100-
ALEXANDER NC-CALDWELL NC-CATAWBA NC-DAVIE NC-GRAHAM NC-IREDELL NC-
ROWAN NC-SWAIN NC-
1122 AM EDT WED JUL 14 2004

...SEVERE WEATHER OUTLOOK...

NUMEROUS SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP AHEAD OF A
COLD FRONT APPROACHING THE REGION THIS AFTERNOON. THE AIRMASS ACROSS
THE AREA REMAINS MOIST AND UNSTABLE...AND ANY THUNDERSTORMS THAT
DEVELOP COULD PRODUCE WIND GUSTS TO 60 MPH AND HAIL THE SIZE OF
PENNIES.

A SEVERE THUNDERSTORM WATCH IS ALREADY IN PLACE ACROSS MUCH OF THE
WESTERN CAROLINAS AND NORTHEAST GEORGIA UNTIL 5 PM EDT.
HOWEVER...EVEN LOCATIONS NOT WITHIN THE CURRENT WATCH...AREAS FROM
THE NORTHERN FOOTHILLS TO THE NORTHWEST PIEDMONT OF NORTH
CAROLINA...AND THE EXTREME SOUTHWEST MOUNTAINS OF NORTH
CAROLINA...COULD EXPERIENCE ISOLATED SEVERE THUNDERSTORMS.

AS THE FRONT PASSES LATER THIS AFTERNOON...WEST WINDS ARE EXPECTED TO
INCREASE AND BECOME QUITE GUSTY. THE NATIONAL WEATHER SERVICE WILL
CONTINUE TO MONITOR THE POTENTIAL FOR DAMAGING WINDS BOTH WITH ANY
THUNDERSTORMS AND WITH SUSTAINED WINDS BEHIND THE FRONT. STAY TUNED
TO NOAA WEATHER RADIO...OR YOUR FAVORITE MEDIA OUTLET FOR THE LATEST
UPDATES.

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
148 PM EDT WED JUL 14 2004

GAZ010-017-018-026-028-029-NCZ033>037-048>059-062>072-082-SCZ001>014-
019-150100-
ABBEVILLE SC-ALEXANDER NC-ANDERSON SC-AVERY NC-BUNCOMBE NC-BURKE NC-
CABARRUS NC-CALDWELL NC-CATAWBA NC-CHEROKEE SC-CHESTER SC-
CLEVELAND NC-DAVIE NC-ELBERT GA-FRANKLIN GA-GASTON NC-GRAHAM NC-
GREATER GREENVILLE SC-GREATER OCONEE SC-GREATER PICKENS SC-
GREENVILLE MOUNTAINS SC-GREENWOOD SC-HABERSHAM GA-HART GA-HAYWOOD NC-
HENDERSON NC-IREDELL NC-LAURENS SC-LINCOLN NC-MACON NC-MADISON NC-
MCDOWELL NC-MECKLENBURG NC-MITCHELL NC-NORTHERN JACKSON NC-
OCONEE MOUNTAINS SC-PICKENS MOUNTAINS SC-POLK NC-RABUN GA-ROWAN NC-
RUTHERFORD NC-SOUTHERN JACKSON NC-SPARTANBURG SC-STEPHENS GA-
SWAIN NC-TRANSYLVANIA NC-UNION SC-UNION NC-YANCEY NC-YORK SC-
148 PM EDT WED JUL 14 2004

...ISOLATED SEVERE STORMS STILL POSSIBLE THROUGH THIS EVENING ACROSS
THE WESTERN CAROLINAS AND NORTHEAST GEORGIA...

SEVERE THUNDERSTORM WATCH NUMBER 629...WHICH WAS IN EFFECT FOR MUCH
OF THE WESTERN CAROLINAS AND NORTHEAST GEORGIA THIS AFTERNOON HAS
BEEN CANCELED. HOWEVER...A STRONG COLD FRONT IS STILL EXPECTED TO
ENTER THE WESTERN CAROLINAS AND NORTHEAST GEORGIA LATER THIS
AFTERNOON. ITS ARRIVAL WILL COINCIDE WITH THE WARMEST PART OF THE
DAY...WHICH WILL ALLOW SHOWERS AND STORMS TO DEVELOP AHEAD OF THE
FRONT. WIND FIELDS IN THE ATMOSPHERE ARE QUITE STRONG TODAY...WHICH
MEANS THAT ANY STORMS THAT DEVELOP WILL HAVE THE POTENTIAL TO PRODUCE
DESTRUCTIVE WIND GUSTS AND POSSIBLY LARGE HAIL.

AFTER THE FRONT PASSES EARLY THIS EVENING...WEST WINDS ARE EXPECTED
TO INCREASE AND BECOME QUITE GUSTY. THE NATIONAL WEATHER SERVICE WILL
CONTINUE TO MONITOR THE POTENTIAL FOR DAMAGING WINDS...BOTH WITH ANY
THUNDERSTORMS AND WITH SUSTAINED WINDS BEHIND THE FRONT. STAY TUNED
TO NOAA WEATHER RADIO...OR YOUR FAVORITE MEDIA OUTLET FOR THE LATEST
STATEMENTS.

LAMB