Hail and Damaging Winds in South Carolina, August 17, 2007

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
251 PM EDT FRI AUG 17 2007

.SYNOPSIS...
HOT UPPER LEVEL RIDGE OVER THE LOWER MS RIVER VALLEY WITH A TROUGH
OF LOW PRESSURE CROSSING THE NORTHEAST PART OF THE COUNTRY THROUGH
SATURDAY. A WEAK COLD FRONT WILL ATTEMPT TO MOVE INTO THE AREA
TONIGHT.

&&

.NEAR TERM /THROUGH TONIGHT/...
POTENTIAL FOR A FEW SEVERE STORMS REMAINS DURING THE AFTERNOON AND
EVENING HOURS ACROSS THE AREA. HOWEVER...18Z SOUNDING FROM CHS
STILL SHOWS DECENT LOW LEVEL CAP...AND LATEST RADAR LOOP SHOWING
NO REAL CONVECTIVE ACTIVITY AT THIS TIME. UPPER LEVEL RIDGE WEST OF
THE REGION THIS AFTERNOON. UPPER TROUGH MOVING THROUGH THE GREAT
LAKES REGION AND NEW ENGLAND WILL PUSH A COLD FRONT INTO THE AREA
TONIGHT. LEE SIDE TROUGH LINGERS OVER THE CAROLINAS TODAY.
MODERATE TO STRONG INSTABILITY ACROSS THE AREA WITH PH20 >1.75
INCHES. STRONG HEATING THIS AFTERNOON WITH TEMPS ONCE AGAIN IN THE
UPPER 90S.

IN SPITE OF WARM TEMPS ALOFT SHOULD SEE AT LEAST SCATTERED
CONVECTION DEVELOP LATER THIS AFTERNOON DURING THE PEAK HEATING OF
THE DAY. HIGH LFC AND WEAK SHEAR. CANNOT RULE OUT ISOLATED SEVERE
STORMS LATE AFTERNOON INTO THE EVENING. SOMEWHAT DRIER AIR
FILTERS IN FOR SATURDAY BUT WEAK COLD FRONT MAY HAVE DIFFICULTY
ADVANCING FAR INTO SC BEFORE POSSIBLY WASHING OUT ON SATURDAY.

AS FOR HEAT ADVISORY...WILL BE BORDERLINE. HOWEVER...ELECTED TO KEEP
HEAT ADVISORY ACROSS ALL BUT THE NORTH MIDLANDS UNTIL 7 PM.
INCREASING HIGH CLOUDS HAVE HELPED TO KEEP TEMPS FROM CLIMBING AS
RAPIDLY AS PREVIOUSLY THOUGHT. HAVE LOWERED AFTERNOON MAX TEMPS
SLIGHTLY. EVEN WITH THE SLIGHTLY LOWER TEMPS...ADVISORY CRITERIA MAY BE
MET FOR BRIEF PERIODS THIS AFTERNOON.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
MODELS IN GENERAL INDICATE THAT THE WEAK COLD FRONT MAY STALL OR
WASH OUT OVER SC BY SATURDAY. HOWEVER ENOUGH DRIER AIR SHOULD
FILTER INTO THE AREA THAT WILL KEEP POPS BELOW SLIGHT CHANCE. HIGH
TEMPS IN THE MID/UPR 90S AND LOWS COOLING TO THE UPR 60S/MIDW
70S.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
THE CHANCES FOR PRECIPITATION LOOK SLIM AS WE WILL AGAIN BE
INFLUENCED BY ANOTHER DRY AIR MASS. TYPICAL SUMMER PATTERN EARLY
NEXT WEEK WITH BERMUDA HIGH EXTENDING WEST...FRONTAL SYSTEM NORTH
OF THE AREA. POPS CLOSE TO CLIMATOLOGY WITH MAINLY SLIGHT CHANCE
AFTERNOON THUNDERSTORMS FOR MUCH OF THE PERIOD. FORECAST MAX TEMPS
MOSTLY IN THE MID TO UPPER 90S.

&&

.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
WEAK SHORT WAVE AND COLD FRONT CONTINUE TO APPROACH THE AREA FROM
THE NORTH. THE MAIN CONCERN IS FOR SCATTERED THUNDERSTORMS THIS
AFTERNOON AND EVENING...20Z-06Z SATURDAY MORNING TIME FRAME.

SURFACE HEAT INDUCED LOW PRESSURE TROUGH WILL DEVELOP AHEAD OF THE
APPROACHING COLD FRONT. WE CONTINUE TO SEE A GOOD SETUP FOR
THUNDERSTORM DEVELOPMENT.  HOWEVER CONVECTIVE TEMPERATURES ARE
HIGH...99 DEG F JUST BELOW THE HIGHS OF 100. INITIAL THUNDERSTORM
DEVELOPMENT PROBABLY PULSE BUT SHOULD EVOLVE INTO MULTICELLULAR. A
FEW THUNDERSTORMS MAY APPROACH SEVERE LIMITS WITH WIND GUSTS OF
40-60 MPH. SPC CONTINUES TO HAVE THE CAE CWA OUTLOOKED IN A SLIGHT
RISK AREA THIS AFTERNOON. WILL CONTINUE WITH MENTION OF CB IN TAFS
FOR THIS AFTERNOON.  TIMING AND CONFIDENCE OF ANY PARTICULAR
THUNDERSTORM AFFECTING TAF SITES IS LOW.

AVIATION OUTLOOK...
NO SIGNIFICANT IMPACTS TO AVIATION EXPECTED SATURDAY THROUGH
TUESDAY.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR SCZ018-025>031-
     035>038-041.
GA...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR GAZ040-063>065-
     077.

&&

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE COLUMBIA SC
1207 PM EDT FRI AUG 17 2007

SCZ015-016-020>022-180915-
LANCASTER-CHESTERFIELD-NEWBERRY-FAIRFIELD-KERSHAW-
1207 PM EDT FRI AUG 17 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL SOUTH CAROLINA.

.DAY ONE...THIS AFTERNOON AND TONIGHT

HEAT...HEAT INDEX VALUES EXPECTED TO REACH 100 TO 105 THIS
AFTERNOON.

SEVERE THUNDERSTORMS...SCATTERED THUNDERSTORMS ARE EXPECTED DURING
THE HEAT OF THE AFTERNOON. A FEW OF THESE STORMS MAY APPROACH
SEVERE LIMITS WITH WIND GUSTS OF 40 TO 60 MPH.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

HEAT...HEAT INDEX VALUES 100 TO 105 MONDAY AFTERNOON.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED.

GAZ040-063>065-077-SCZ018-025>031-035>038-041-180915-
LINCOLN-MCDUFFIE-COLUMBIA-RICHMOND-BURKE-MCCORMICK-EDGEFIELD-SALUDA-
LEXINGTON-RICHLAND-LEE-AIKEN-SUMTER-BARNWELL-ORANGEBURG-CALHOUN-
CLARENDON-BAMBERG-
1207 PM EDT FRI AUG 17 2007

...HEAT ADVISORY IN EFFECT UNTIL 7 PM EDT THIS EVENING...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR EAST CENTRAL GEORGIA AND
CENTRAL SOUTH CAROLINA.

.DAY ONE...THIS AFTERNOON AND TONIGHT

PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE
INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS.

   HEAT ADVISORY.

SEVERE THUNDERSTORMS...SCATTERED THUNDERSTORMS ARE EXPECTED DURING
THE HEAT OF THE AFTERNOON. A FEW OF THESE STORMS MAY APPROACH
SEVERE LIMITS WITH WIND GUSTS OF 40 TO 60 MPH.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

HEAT...HEAT INDEX VALUES 100 TO 105 MONDAY AFTERNOON.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED.