Heat Advisory 3, NWS Columbia, SC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
1214 PM EDT THU JUL 26 2012

.SYNOPSIS...
AN UPPER LEVEL RIDGE WILL BUILD OVER THE SOUTHEAST TODAY AND MOVE
OFF THE ATLANTIC COAST ON FRIDAY. A COLD FRONT WILL ATTEMPT TO
PUSH INTO THE CAROLINAS FROM THE NORTH LATE FRIDAY INTO SATURDAY.
EXPECT THE CHANCE FOR MAINLY AFTERNOON AND EVENING SHOWERS AND
THUNDERSTORMS TO SLOWLY INCREASE INTO THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
LATEST LAPS SOUNDINGS INDICATING THAT MIXING OF DRIER AIR ALOFT IS
DEVELOPING WITH DEW POINTS DROPPING IN THE AFTERNOON...CURRENTLY
IN THE UPPER 60S. SO EXPECT HEAT INDEX VALUES IN THE 105 TO 110
RANGE MOST AREAS BUT SOUTHEAST MIDLANDS WILL ISSUE HEAT ADVISORY
FOR HEAT INDEX VALUES AROUND 110. LFC IS ABOVE 7000 FT AND THE
TEMPERATURE AT 700 MB IS 11C...WHICH SHOULD LIMIT CONVECTION.
TEMPERATURES IN THE LOWER 100'S...WILL RAISE TEMPERATURES SLIGHTLY
BASED ON CURRENT TRENDS. DESPITE AIR MASS BEING MODERATELY TO
STRONGLY UNSTABLE...LOWERED POPS ALL AREAS THIS AFTERNOON BASED ON
LIKELY CAPPED ENVIRONMENT.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
NOT MUCH CHANGE FOR FRIDAY. THE UPPER LEVEL RIDGE WILL MIGRATE
EASTWARD OFF THE ATLANTIC COAST ON FRIDAY AS AN UPPER TROUGH
BECOMES A LITTLE BIT MORE PRONOUNCED. WEAK SURFACE RIDGING WILL
LINGER OVER THE SOUTHEASTERN STATES WITH A THERMAL TROUGH
EXTENDING FROM VIRGINIA THROUGH THE CAROLINAS.

MODERATE TO STRONG INSTABILITY ALONG WITH PRECIPITABLE WATER VALUES
HOVERING AROUND THE 2 INCH RANGE WITH KEEP THE THREAT OF MAINLY
DIURNAL CONVECTION OVER THE REGION THROUGH THE SHORT TERM.
TEMPERATURES WILL BE ABOVE NORMAL WITH HIGHS AROUND 100 AND LOWS
IN THE 70S.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
VERY LITTLE CHANGES TO THE EXTENDED FORECAST. AN UPPER TROUGH
WILL RESIDE OVER THE EASTERN THIRD OF THE NATION WITH RIDGE
HOLDING ACROSS THE WESTERN STATES. A LEE- SIDE TROUGH LINGERING
ACROSS THE CAROLINAS WITH PRECIPITABLE WATER VALUES AROUND 2
INCHES...COMBINED WITH MODERATE TO STRONG INSTABILITY WILL ALLOW
SCATTERED TO NUMEROUS THUNDERSTORMS TO DEVELOP ACROSS THE AREA
SATURDAY. A FRONTAL BOUNDARY IS EXPECTED TO MOVE SOUTHWARD INTO
THE AREA SUNDAY AND LINGER INTO WEDNESDAY. THIS BOUNDARY WILL BE
THE FOCUS FOR (MAINLY DIURNAL) CONVECTION FOR THE FIRST HALF OF
NEXT WEEK.

ABOVE NORMAL TEMPERATURES OVER THE WEEKEND MAY COOL TO NEAR NORMAL
IF THE FRONT IS ALLOWED TO SINK SOUTH OF THE AREA.

&&

.AVIATION /16Z THURSDAY THROUGH MONDAY/...
VFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH THE TAF
PERIOD.. THROUGH THE DAY...CUMULUS CLOUDS WILL BEGIN TO DEVELOP
DURING THE EARLY AFTERNOON HOURS. CONVECTION AT MOST SHOULD BE
ISOLATED DUE TO CAPPED ENVIRONMENT AND LACK OF TRIGGER. SURFACE WINDS
WILL INCREASE TO AROUND 10 KNOTS...WITH SOME HIGHER GUSTS BEING
POSSIBLE IN THE AFTERNOON. WINDS WILL DIMINISH AFTER SUNSET.

EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE EACH DAY DUE TO
AFTERNOON CONVECTION AS A MOIST AIR MASS REMAINS OVER THE REGION.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...HEAT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR SCZ035>038-041.
GA...HEAT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR GAZ077.
&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE COLUMBIA SC
558 AM EDT THU JUL 26 2012

GAZ040-063>065-077-SCZ015-016-018-020>022-025>031-035>038-041-271000-
LINCOLN-MCDUFFIE-COLUMBIA-RICHMOND-BURKE-LANCASTER-CHESTERFIELD-
MCCORMICK-NEWBERRY-FAIRFIELD-KERSHAW-EDGEFIELD-SALUDA-LEXINGTON-
RICHLAND-LEE-AIKEN-SUMTER-BARNWELL-ORANGEBURG-CALHOUN-CLARENDON-
BAMBERG-
558 AM EDT THU JUL 26 2012

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

.DAY ONE...TODAY AND TONIGHT.

THE COMBINATION OF TEMPERATURES AROUND 100 DEGREES AND LOW-LEVEL
MOISTURE WILL PUSH AFTERNOON HEAT INDICES TO BETWEEN 105 AND 109
DEGREES AT TIMES TODAY. IN ADDITION THERE WILL BE A POSSIBILITY OF
AN ISOLATED STRONG THUNDERSTORM ACROSS THE REGION THIS AFTERNOON
AND EVENING...WITH THE MAIN THREAT BEING DOWNBURST WINDS IN ANY
STORMS THAT DEVELOP.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.