Severe Thunderstorm Warning 183, NWS Greenville-Spartanburg, SC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
302 PM EDT SAT JUN 23 2007

.SYNOPSIS...
A TYPICAL SUMMERTIME PATTERN WILL CONTINUE ACROSS NORTHEAST GEORGIA
AND THE WESTERN CAROLINAS OVER THE NEXT SEVERAL DAYS AS SUBTROPICAL
HIGH PRESSURE ANCHORS OVER THE ATLANTIC BY EARLY NEXT WEEK.
EVENTUALLY...THIS HIGH WILL WEAKEN AND PUSH EASTWARD AS A FRONTAL
BOUNDARY APPROACHES THE REGION LATE NEXT WEEK.

&&

.NEAR TERM /THROUGH SUNDAY/...
FOR THE REMAINDER OF THE AFTERNOON...ENHANCED CU FIELD OVER THE
HIGHER TERRAIN SHOULD CONTINUE TO GROW INTO SCATTERED
THUNDERSTORMS...A FEW WHICH COULD MOVE OUT ACROSS THE FOOTHILLS AND
PIEDMONT THIS EVENING. OTHERWISE...IT SHOULD BE QUIET OVERNIGHT AS
HIGH PRESSURE DRIFTS DOWN FROM THE GT LAKES TO THE MID ATLANTIC.
WHAT REMAINS TO BE SEEN IS IF WEAK EASTERLY FLOW DEVELOPING AFTER
MIDNIGHT CAN FORCE ANY LOW CLOUDS OR LIGHT PRECIP NEAR THE BLUE
RIDGE AS SUGGESTED BY THE MODELS. FOR NOW...THE POP WILL BE KEPT LOW
SINCE CONFIDENCE IN THIS IS LOW.

ON SUNDAY...UPPER RIDGING BUILDS ACROSS THE WESTERN CAROLINAS WITH
HIGH PRESSURE MOVING PAST TO THE NORTH. THE NAM SOLUTION LOOKS
SKETCHY AS IT BLOWS UP A LARGE AREA OF PRECIP OVER THE MIDDLE OF
NC...WHICH GREATLY AFFECTS THE MAX TEMP FORECAST. WILL FOLLOW THE
GFS MAINLY...WHICH SUGGESTS THAT DIURNAL CONVECTION WILL ONCE AGAIN
FIRE ACROSS THE HIGHER TERRAIN. TEMPS WERE NUDGED TOWARD THE MAV.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
A WEAK UPPER LEVEL RIDGE OVER THE SOUTHEAST BECOMES BETTER DEFINED
ON MONDAY AND TUESDAY WHILE A WEAK UPPER LOW UPSTREAM RETROGRESSES
INTO TX...AND AN EASTERN CANADIAN TROUGH PROGRESSES OUT TO SEA. THE
REMAINS OF THE OLD SURFACE BOUNDARY WILL LIFT NORTH OVER OUR
AREA...CAUSING SURFACE WINDS TO VEER FROM SOUTHEAST...TO SOUTH...TO
SOUTHWEST. INITIALLY POPS AND QPF  WILL BE MOST FAVORED ON THE NC
BLUE RIDGE IN AN EASTERLY COMPONENT...BUT AS THE FLOW BECOMES MORE
SOUTHERLY...THE GA/SC ESCARPMENT WILL BE MORE FAVORED. ALTHOUGH
UPPER LEVEL FORCING WILL BE LACKING...THE LIGHT UPSLOPE COMPONENT
WILL KEEP POPS GOING INTO THE EVENING SUN NIGHT AND MONDAY NIGHT. BY
TUESDAY WITH SOUTHWESTERLY FLOW PARALLEL TO THE MOUNTAINS...
DIFFERENTIAL HEATING OF SLOPES WILL DICTATE THE HIGHEST POPS AND
QPF...WITH ACTIVITY SHUTTING DOWN EARLY IN THE EVENING. MODEL
GUIDANCE MAXIMUM TEMPERATURES TREND DOWNWARD...DESPITE SLIGHTLY
INCREASING HEIGHTS ALOFT AND A MORE SOUTHERLY COMPONENT TO THE
SURFACE FLOW. THE FORECAST MAXIMUMS LEANED TOWARD THE HIGHER END OF
GUIDANCE IN AN ATTEMPT TO MINIMIZE OR SLIGHTLY REVERSE THE COOLING.
MINIMUM TEMPERATURES WILL CRAWL UPWARD WITH RISING DEW POINTS.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
NO SIGNIFICANT CHANGES WERE MADE TO THE LATTER PART OF THE EXTENDED
FORECAST WITH THIS PACKAGE. THINKING IS PRETTY MUCH THE SAME AS
YESTERDAY AS UPPER HIGH MOVES OFF THE COAST LATE IN THE WEEK WITH AN
EASTERN TROUGH DEVELOPING AND STICKING AROUND THROUGH THE WEEKEND.
HPC CONTINUES TO SHOW A COLD FRONT APPROACHING THE FA ON
FRIDAY...BEFORE STALLING OUT ACROSS THE NORTHERN PART OF THE AREA ON
SATURDAY. NORMAL TO ABOVE NORMAL TEMPERATURES EXPECTED THROUGHOUT
THIS PERIOD OF THE FORECAST WITH TYPICAL SUMMERTIME DIURNAL
CONVECTION CHANCES REFLECTED IN POPS.

&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
A HIGH BASED CUMULUS FIELD SHOULD CONTINUE TO GROW THROUGH THE
AFTERNOON WITH CLOUDS REMAINING SCATTERED IN MOST LOCATIONS. KAVL
HAS THE BEST CHANCE OF SEEING A TEMPORARY VFR CEILING WITH SCATTERED
THUNDERSTORMS SO IT WILL BE INCLUDED THERE. OTHERWISE A LIGHT NE
FLOW WILL PREVAIL WITH A WEAK SURFACE BOUNDARY TO OUR SOUTH. SOME
MID/HIGH LEVEL CLOUD DEBRIS IS EXPECTED OVERNIGHT WITH THE PASSAGE
OF THE LAST IN A SERIES OF WEAK WAVES FROM THE NORTHWEST. SOME
MARGINAL VISIBILITY PROBLEMS ARE ANTICIPATED DURING THE EARLY
MORNING HOURS PARTICULARY AT KAVL...WHICH HAS A DECENT CHANCE AT
GOING MVFR AFTER 08Z OR SO...ESPECIALLY IF THEY HAVE A SHOWER THIS
AFTERNOON. THE FOG SHOULD DISSIPATE AT ALL SITES NO LATER THAN 15Z
WITH CUMULUS DEVELOPING IN THE LATE MORNING.

LOOKING AHEAD...THE GUIDANCE SUGGESTS AN MVFR VISIBILITY PROBLEM
LATE SUNDAY NIGHT OR EARLY MONDAY MORNING. ONCE SURFACE HIGH
PRESSURE MOVES OFF THE COAST EARLY IN THE WEEK...A LIGHT SOUTH OR
SOUTHEAST RETURN MOISTURE FLOW MEANS THE POSSIBILITY OF MVFR
CEILINGS TUESDAY MORNING AND WEDNESDAY MORNING...BEFORE CLOUDS
SCATTER AND RISE WITH THE BOUNDARY LAYER IN MIDDAY. THE NEXT BEST
CHANCE FOR THUNDERSTORMS/PRECIPITATION WILL NOT BE UNTIL LATE IN THE
WEEK...ALTHOUGH THUNDERSTORMS WILL BE POSSIBLE ACROSS THE MOUNTAINS
IN THE AFTERNOON AND EVENING ESSENTIALLY EVERY DAY.

&&

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

&&

SYNOPSIS...BSH
NEAR TERM...PM
SHORT TERM...JAT
LONG TERM...BSH
AVIATION...PM

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
654 AM EDT SAT JUN 23 2007

NCZ033-048>053-058-059-062>065-501-503-505-507-509-241100-
AVERY-MADISON-YANCEY-MITCHELL-SWAIN-HAYWOOD-BUNCOMBE-GRAHAM-
NORTHERN JACKSON-MACON-SOUTHERN JACKSON-TRANSYLVANIA-HENDERSON-
CALDWELL MOUNTAINS-BURKE MOUNTAINS-MCDOWELL MOUNTAINS-
RUTHERFORD MOUNTAINS-POLK MOUNTAINS-
654 AM EDT SAT JUN 23 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN NORTH CAROLINA.

.DAY ONE...TODAY AND TONIGHT

ISOLATED TO WIDELY SCATTERED SHOWERS AND THUNDERSTORMS WILL
DEVELOP OVER THE MOUNTAINS THIS AFTERNOON AND THIS EVENING.
LOCALLY HEAVY RAINFALL AND FREQUENT CLOUD TO GROUND LIGHTNING WILL
BE THE MAIN THREATS. HOWEVER...AN ISOLATED DAMAGING WIND GUST OR
LARGE HAIL EVENT CANNOT BE RULED OUT.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

GAZ010-017-018-026-028-029-NCZ035>037-056-057-068>072-082-502-504-
506-508-510-SCZ001>014-019-241100-
RABUN-HABERSHAM-STEPHENS-FRANKLIN-HART-ELBERT-ALEXANDER-IREDELL-
DAVIE-CATAWBA-ROWAN-CLEVELAND-LINCOLN-GASTON-MECKLENBURG-CABARRUS-
UNION NC-GREATER CALDWELL-GREATER BURKE-EASTERN MCDOWELL-
GREATER RUTHERFORD-EASTERN POLK-OCONEE MOUNTAINS-PICKENS MOUNTAINS-
GREENVILLE MOUNTAINS-GREATER OCONEE-GREATER PICKENS-
GREATER GREENVILLE-SPARTANBURG-CHEROKEE-YORK-ANDERSON-ABBEVILLE-
LAURENS-UNION SC-CHESTER-GREENWOOD-
654 AM EDT SAT JUN 23 2007

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

.DAY ONE...TODAY AND TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

LANE