Flash Flood Warning 17, NWS Greenville-Spartanburg, SC

AREA FORECAST DISCUSSION....UPDATED
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
721 AM EDT MON JUN 21 2004

.SHORT TERM (MONDAY THROUGH WEDNESDAY)...
UPDATING TO MOVE UP BEST POPS TO THIS MORNING PER RECENT RADAR
TRENDS.

UPPER LEVEL IMPULSE TO MOVE E ACROSS AREA IN ZONAL FLOW TODAY...
WHILE FRONT TO S STARTS RETURN N. GUIDANCE CATEGORICAL IN SW...AND
CHANCE IN NE.HEAVIEST RAIN S BLUE RIDGE ESCARPMENT. SYSTEM MOVES
THROUGH THIS EVENING...AND AREA ENTERS A RELTATIVE LULL LATE TONIGHT
AND TUE...THOUGH ENOUGH MOISTURE/INSTABILITY LEFT FOR CHANCE POPS.
UPPER LEVEL THROUGH TO AMPLIFY CENTER OF CONTINENT TUE. NEXT COLD
FRONT APPROACHES FROM NW TUE NIGHT...CROSSING AREA WED. AT THIS TIME
CARRYING HGIH CHANCE POP WITH FRONT...EXCEPT LOW END LIKELY SAVANNAH
RIVER VALLEY. DRYING BEHIND FRONT INDICATED WED NIGHT. TEMPERATURES
COOLER TODAY IN CLOUDS/RAIN...THEN A BIT WARMER TUE/WED BEFORE FROPA.

.LONG TERM (MONDAY THROUGH WEDNESDAY)...
NEW GFS RUN WOULD SUGGEST DRY THU WITH BOUNDARY STALLED TO S OF
AREA. AT THIS TIME WILL LEAVE SMALL CHANCE DIURNAL POP IN THU UNTIL
NCEP SHEDS LIGHT ON PREFERRED MEDIUM RANGE SOLUTION. GFS BRINGS
REMANANTS OF FRONT N FRI TOWARD NCEP SOLUTION...AND DIURNAL CHANCE
POPS CONTINUE INTO SAT. CHACNE POPS SAT NGITH AND SUN AS NEXT WAVE
RIDES ALONG STATIONARY FRONT. PROSPECT FOR THU BEING COOLER THAN
CURRENT FORECAST IF NEW GFS RUN ACCEPTED...FOLLOWED GRADUAL COOLING
AS UPPER TROUGH PROGRESSES AND HEIGHTS FALL.

&&

.AVIATION...
SOME SHRA HAVE DEVELOPED ACROSS THE WRN UPSTATE...AND EXPECT THEM TO
REMAIN THERE FOR SEVERAL MORE HRS. BOTH THE MET AND MAV GUIDANCE
HAVE CIGS AND VSBYS FALLING INTO THE MVFR RANGE GENERALLY BETWEEN 9
AND 12 UTC. THIS HAPPENS AS ISENTROPIC UPGLIDE DEVELOPS OVER THE
SOMEWHAT COOLER AND DRIER AIRMASS BANKED ALONG THE LEE SLOPES.
SUSPECT THAT CLT...BEING DEEPER UNDER THE REMAINING COLD AIR DAMMING
WL BE LAST TO SEE CIGS AND VSBYS FALL...AND LAST TO SEE PCPN. DON/T
HAVE MVFR CIGS THERE UNTIL THIS EVENING. WITH WEAK UPGLIDE AND A
VERY MOIST AIRMASS...HARD TO SAY EXACTLY WHEN THE MVFR CIGS WL FILL
IN ACROSS THE UPSTATE. HOWEVER...ONCE UPGLIDE BECOMES ESTABLISHED...
IN SITU DAMMING WL RESULT IN WIDESPREAD PCPN ACROSS THE UPSTATE AND
SRN MTNS. FOR NOW...AM BRINGING IN LOW CIGS A FEW HOURS LATER THAN
THE MOS...RIGHT AROUND 12 UTC. AT THE SAME TIME...WL ALSO LOWER
VSBYS TO 5SM AND GO WITH PREVAILING SHRA. EXPECT SIMILAR CONDITIONS
AT AVL AS CAD CONDITIONS IN THE SRN MTNS WON/T BE THAT DIFFERENT
FROM THE UPSTATE.

&&

.PRELIMINARY POINT TEMPS/POPS...
GSP  80  67  86  70 /  70  50  40  40
AND  82  68  87  69 /  80  50  40  40
CLT  82  68  86  69 /  60  50  40  40
HKY  80  65  85  67 /  60  50  40  40
AVL  76  63  81  64 /  70  50  50  50
&&

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

SHORT/LONG TERM: JAT
AVIATION: BPM

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
547 AM EDT MON JUN 21 2004

GAZ010-017-018-026-028-029-NCZ033>037-048>059-062>072-082-SCZ001>014-
019-220947-
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-
541 AM EDT MON JUN 21 2004

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

.DAY ONE...
NUMEROUS THUNDERSTORMS ARE EXPECTED TODAY AND TONIGHT...SOME OF WHICH
MAY PRODUCE LOCALLY HEAVY RAINFALL.

.DAYS TWO THROUGH SEVEN...

SCATTERED THUNDERSTORMS ARE EXPECTED ACROSS THE WESTERN CAROLINAS AND
NORTHEAST GEORGIA FROM TUESDAY THROUGH SUNDAY. THERE IS A SLIGHT RISK
OF SEVERE THUNDERSTORMS PRODUCING DAMAGING WIND TUESDAY IN NORTH
CAROLINA...NORTH AND WEST OF THE CHARLOTTE AREA.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED.

07

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
658 AM EDT MON JUN 21 2004

SCZ006>014-019-211227-
ABBEVILLE SC-ANDERSON SC-CHEROKEE SC-CHESTER SC-
GREATER GREENVILLE SC-GREENWOOD SC-LAURENS SC-SPARTANBURG SC-
UNION SC-YORK SC-
704 AM EDT MON JUN 21 2004

...THUNDERSTORMS PRODUCING TORRENTIAL RAIN AND LIGHTNING OVER PARTS
OF THE UPSTATE...

AT 700 AM EDT...WEATHER SERVICE RADAR INDICATED TWO CLUSTERS OF
THUNDERSTORMS WITH TORRENTIAL RAIN AND FREQUENT LIGHTNING OVER THE
UPSTATE. THE FIRST CLUSTER OF STORMS WAS AFFECTING AREAS FROM
LOWNDESVILLE TO ANDERSON. RADAR ESTIMATED THAT 2 TO 3 INCHES OF RAIN
HAD FALLEN IN THE LOWNDESVILLE AREA. THESE STORMS WILL MOVE UP
INTERSTATE 85 AND AFFECT MUCH OF CENTRAL AND SOUTHERN GREENVILLE
COUNTY THROUGH 8 AM.

ANOTHER AREA OF THUNDERSTORMS WAS AFFECTING CENTRAL SPARTANBURG
COUNTY. RADAR ESTIMATED THAT AROUND 2 INCHES OF RAIN HAD FALLEN IN
THE SPARTANBURG METRO AREA DURING THE PAST HOUR. ADDITIONAL
THUNDERSTORMS WERE DEVELOPING WEST OF CITY...AND UP TO ANOTHER INCH
OF RAIN MAY FALL. THIS WILL RESULT IN DEEP PONDING OF WATER IN LOW
SPOTS AND POOR DRAINAGE AREAS. VISIBILITIES WILL BE GREATLY REDUCED
IN THE RAIN. THE STORMS WERE ALSO PRODUCING FREQUENT CLOUD TO GROUND
LIGHTNING...AND THERE MAY EVEN BE SOME SMALL HAIL.

MCAVOY

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
815 AM EDT MON JUN 21 2004

GAZ026-028-029-211337-
ELBERT GA-FRANKLIN GA-HART GA-
815 AM EDT MON JUN 21 2004

...TORRENTIAL RAIN AND FREQUENT LIGHTNING AFFECTING PARTS OF
NORTHEAST GEORGIA...

AT 810 AM EDT...WEATHER SERVICE RADAR INDICATED A NEARLY STATIONARY
LINE OF THUNDERSTORMS EXTENDING ALONG A LINE FROM CARNESVILLE TO
HARTWELL AND THE NORTH SIDE OF ELBERTON. RADAR ESTIMATES THAT 1 TO 2
INCHES OF RAIN HAS ALREADY FALLEN IN THIS AREA DURING THE PAST HOUR.
AS THE STORMS ARE NOT MOVING...AN ADDITIONAL 1 TO 2 INCHES OF RAIN
WILL BE POSSIBLE. THIS CAUSE STREAMS TO RISE TO BANKFULL AND RESULT
IN DEEP PONDING OF WATER IN LOW SPOTS AND POOR DRAINAGE AREAS.

THE STRONGEST STORMS IN THIS AREA ARE ALSO PRODUCING A GREAT DEAL OF
CLOUD TO GROUND LIGHTING...30 TO 40 MPH WINDS AND SMALL HAIL.

SCZ006>009-012>014-211337-
CHEROKEE SC-CHESTER SC-GREATER GREENVILLE SC-LAURENS SC-
SPARTANBURG SC-UNION SC-YORK SC-
808 AM EDT MON JUN 21 2004

...VERY HEAVY RAIN AND FREQUENT LIGHTNING IN THE
GREENVILLE-SPARTANBURG METRO AREA...

AT 800 AM EDT...WEATHER SERVICE RADAR INDICATED A LINE OF
THUNDERSTORMS ACROSS THE GREENVILLE-SPARTANBURG METRO AREA...AND
EXTENDING AS FAR SOUTH AS SIMPSONVILLE AND MOORE. INDIVIDUAL CELLS IN
THE LINE ARE MOVING NORTHEAST AT 25 MPH...BUT THE LINE ITSELF IS
NEARLY STATIONARY. RADAR ESTIMATES THAT 2 TO 3 INCHES OF RAIN HAS
FALLEN ACROSS MUCH OF CENTRAL SPARTANBURG COUNTY. STREAMS WILL FILL
TO NEAR BANKFULL AND LOW AREAS WILL EXPERIENCE DEEP PONDING OF WATER
IN THE METRO AREAS.

THESE STORMS WERE ALSO PRODUCING FREQUENT CLOUD TO GROUND LIGHTNING
AND IN SOME CASES WIND GUSTS TO AROUND 30 MPH.

MCAVOY