Damaging Wind in North Carolina, July 28, 2013

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
402 PM EDT SUN JUL 28 2013

.SYNOPSIS...
SURFACE HIGH PRESSURE AND SLIGHTLY DRIER AIR WILL GRADUALLY WORK
THEIR WAY INTO THE REGION TONIGHT AND TOMORROW AND REMAIN THROUGH
TUESDAY. ANOTHER COLD FRONT WILL APPROACH THE REGION AROUND MID WEEK
AND BRING MORE SHOWERS AND THUNDERSTORMS TO THE AREA.

&&

.NEAR TERM /THROUGH MONDAY/...
2000 UTC UPDATE...POPS AND QPF WERE ADJUSTED TO ACCOUNT FOR
CONVECTION IN THE NC FOOTHILLS AND UPPER SAVANNAH RIVER VALLEY. SKY
COVER WAS ADJUSTED PER SATELLITE IMAGERY.

PREVIOUS DISCUSSION...ISOLATED CONVECTION CONTINUES TO DEVELOP OVER
THE HIGH TERRAIN THIS AFTERNOON...WITH EVEN A FEW CELLS POPPING UP
OVER THE NORTHWEST NC PIEDMONT AND NORTHERN FOOTHILLS. CAPE IS
MODERATELY STRONG (>2000 J/KG) ACROSS MUCH OF THE EASTERN HALF OF
THE AREA...WHILE DCAPE IS QUITE HIGH. EXPECT CONVECTION OVER THE
HIGH TERRAIN TO CONTINUE TO INCREASE IN COVERAGE AND DEVELOP SOME
ACTIVE OUTFLOW BOUNDARIES... WITH COVERAGE PERHAPS INCREASING AS MTN
CONVECTION PUSHES OUT INTO THE FOOTHILLS AND PIEDMONT. THE BEST
COVERAGE (40 TO 50 POPS) IS EXPECTED ACROSS THE NC ZONES FROM THE
BLUE RIDGE EAST. WITH DECENT DEEP LAYER SHEAR AND THE STRONG
DCAPE...THERE WILL BE A RISK OF DAMAGING WINDS AND PERHAPS BRIEF
LARGE HAIL WITH THE STRONGER STORMS. CONVECTION SHOULD MOVE EAST OF
THE AREA BY LATE EVENING AS THE WEAK COLD FRONT AND UPPER TROUGH
AXIS PUSH DRIER AIR INTO THE CWA.

SPEAKING OF THE DRIER AIR...MONDAY LOOKS TO BE A DAY RELATIVELY FREE
OF DEEP CONVECTION. DEWPOINTS IN THE 50S (MTNS) AND LOWER TO MID 60S
(FHILLS/PIEDMONT) ALONG WITH WARMING MID-LEVEL TEMPS BENEATH
INCREASINGLY ANTICYCLONIC FLOW ALOFT ARE RESULTING IN FORECAST
SOUNDINGS WITH LITTLE IN THE WAY OF CAPE (EXCEPT ACROSS THE SOUTHERN
AND EASTERN PERIPHERY OF THE FORECAST AREA). THEREFORE...WE ARE
FEATURING A LESS THAN SLIGHT CHANCE FORECAST FOR MONDAY
AFTERNOON...ALTHOUGH I STILL WOULD NOT RULE OUT A COUPLE OF STRAY
CELLS ACROSS THE SOUTHERN AND EASTERN ZONES.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
AS OF 230 PM SUNDAY...ON TUESDAY...LLVL TEMPERATURES AND DEWPOINTS
WILL BEGIN TO MODIFY IN THE WAKE OF THE EARLY WEEK FROPA. HIGH
TEMPERATURES WILL LIKELY REMAIN 2 TO 3 DEGREES BELOW NORMAL...BUT 1
TO 2 DEGREES WARMER THAN MONDAY/S VALUES. AFTERNOON DEWPOINTS SHOULD
REMAIN IN THE MID TO UPPER 60S. NAM12...FORECAST SOUNDINGS INDICATED
THAT THE ENVIRONMENT WILL REMAIN CAPPED THROUGH THE MORNING AND
EARLY AFTERNOON. IN FACT...THE GFS FORECAST SOUNDINGS INDICATE THAT
CONDITIONS WILL REMAIN CAPPED WITH LITTLE TO NO CONDITIONAL
INSTABILITY. BASED ON MODEL AGREEMENT OF THE PLACEMENT AND TIMING OF
MID LEVEL L/W TROF...I WOULD EXPECT THAT AN AFTERNOON INVERTED TROF
WILL DEVELOP ACROSS THE MTNS...INDICATED ON THE NAM. THE INVERTED
TROF COMBINED WITH RIDGETOP CONVERGENCE WILL LIKELY OVERCOME WEAK
LLVL CIN...RESULTING IN MID TO LATE AFTERNOON SHRA/TSRA. I WILL
INCREASE POPS ACROSS THE MTNS TO LOW CHC...KEEPING AREAS EAST OF THE
MTNS WITH A SCHC.

ON WEDNESDAY...CONDITIONS APPEAR SIGNIFICANTLY MORE FAVORABLE FOR
DEEP CONVECTION. THE PRIMARY CONCERN WILL BE THE PLACEMENT AND
TIMING OF A WELL DEFINED S/W. BOTH THE NAM AND GFS INDICATE THAT S/W
WILL RIPPLE ACROSS THE SOUTHERN APPALACHIANS DURING THE HEAT OF THE
AFTERNOON. FORECAST SOUNDINGS CONTINUE TO INDICATE THE PRESENCE OF A
WEAK INVERSION AROUND H6...BUT LLVL CIN APPEARS LESS THAT TUESDAY.
CAPE VALUES MAY RANGE FROM 1500-2000 J/KG. THE COMBINATION OF A LATE
AFTERNOON PASSAGE OF THE MID S/W WITH WEAK TO MODERATE INSTABILITY
WILL SUPPORT SCT TO NUM SHRA/TSRA.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 2PM EDT SUNDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON
THURSDAY WITH A LONGWAVE UPPER TROF SITUATED ACROSS THE EASTERN
CONUS AND UPPER RIDGING OVER THE WESTERN CONUS. THE LONG RANGE
MODELS INDICATE THAT VARIOUS MID TO UPPER LVL SHORTWAVES WILL RIPPLE
OVER THE FCST AREA THRU THE MEDIUM RANGE BUT OVERALL...THE UPPER
TROF WILL REMAIN MOSTLY IN PLACE TO OUR NORTH THRU NEW DAY 7. AT THE
SFC...THE CWFA IS EXPECTED TO BE UNDER A LARGE AREA OF MOIST
SOUTHERLY FLOW AT THE BEGINNING OF THE PERIOD 00Z THURS AS A WEAK
FRONT APPROACHES THE AREA. THE FRONT WILL LIKELY MOVE SOUTHEAST OF
THE CAROLINAS BY LATE THURS INTO EARLY FRI...BRINGING DRIER AIR IN
ITS WAKE. THUS...FRI AND SAT LOOK MOSTLY DRY WITH ONLY CHANCE
DIURNAL POPS AND NEAR NORMAL TEMPS. ON SUN...THE MODELS INDICATE
THAT ANOTHER FRONTAL BNDY WILL MOVE INTO THE CWFA FROM THE NW AND
BRING AN INCREASED CHANCE FOR WIDESPREAD TSRA WITH TEMPS A FEW
DEGREES COOLER.

&&

.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
AT KCLT AND ELSEWHERE...ISOLATED CONVECTION WAS DEVELOPING OVER THE
HIGH TERRAIN AT 1730Z. WITH A MODERATELY UNSTABLE AIR MASS IN
PLACE...CONVECTION SHOULD INCREASE IN COVERAGE AND INTENSITY NEAR
THE BLUE RIDGE OVER THE NEXT COUPLE OF HOURS...AND MOVE FAIRLY
QUICKLY (25 KTS OR SO) TO THE EAST. WITH THIS IN MIND...VCTS HAS
BEEN INTRODUCED AT KAVL BY 19Z AND THE UPSTATE SC TERMINALS AND KHKY
BY 20Z. A TEMPO IS BEING ADVERTISED AT KCLT AFTER 21Z. CONVECTION IS
EXPECTED TO MOVE EAST OF ALL TERMINALS BY LATE EVENING. A WEAK COLD
FRONT MOVING ACROSS THE REGION LATE TODAY AND TONIGHT WILL GRADUALLY
TURN WINDS AROUND TO LIGHT NE BY DAYBREAK MONDAY. UNTIL THEN...THEY
WILL REMAIN SW AT 6-9 KTS...WHILE THUNDERSTORM OUTFLOW MAY CAUSE
BRIEF PERIODS OF GUSTY AND VARIABLE WINDS. ALTHOUGH THE ATMOSPHERE
WILL GRADUALLY DRY OUT LATE TONIGHT INTO EARLY MONDAY...ENOUGH
SHALLOW MOISTURE IS EXPECTED TO BE LEFT TO PRODUCE SOME VALLEY FOG
AND LOW STRATUS TONIGHT...WHILE MVFR CLOUDS ARE EXPECTED ACROSS THE
REMAINDER OF THE AREA.

OUTLOOK...A DRIER AIR MASS IS EXPECTED TO RESULT IN LITTLE TO NO
CONVECTION MONDAY AFTERNOON. ISOLATED/WIDELY SCATTERED CONVECTION IS
POSSIBLE ON TUESDAY...WHILE A RETURN TO AN ACTIVE/WET PATTERN IS
EXPECTED BY MID-WEEK. ANOTHER PERIOD OF DRYING IS POSSIBLE BY NEXT
WEEKEND.

CONFIDENCE TABLE...

            20-02Z        02-08Z        08-14Z        14-20Z
KCLT       HIGH 100%     HIGH  99%     MED   62%     MED   78%
KGSP       HIGH 100%     HIGH  97%     MED   71%     MED   78%
KAVL       HIGH  85%     HIGH  90%     MED   68%     HIGH 100%
KHKY       HIGH 100%     HIGH 100%     HIGH  94%     HIGH 100%
KGMU       HIGH 100%     HIGH 100%     MED   71%     MED   78%
KAND       HIGH 100%     HIGH 100%     HIGH  94%     HIGH 100%

THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)

WWW.WEATHER.GOV/GSP/AVIATION_TABLES

&&

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

&&

SYNOPSIS...WIMBERLEY
NEAR TERM...JAT/JDL
SHORT TERM...NED
LONG TERM...JPT
AVIATION...JDL

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
404 PM EDT SUN JUL 28 2013

GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065-
068>072-082-501>510-SCZ001>014-019-292015-
RABUN-HABERSHAM-STEPHENS-FRANKLIN-HART-ELBERT-AVERY-ALEXANDER-
IREDELL-DAVIE-MADISON-YANCEY-MITCHELL-SWAIN-HAYWOOD-BUNCOMBE-CATAWBA-
ROWAN-GRAHAM-NORTHERN JACKSON-MACON-SOUTHERN JACKSON-TRANSYLVANIA-
HENDERSON-CLEVELAND-LINCOLN-GASTON-MECKLENBURG-CABARRUS-UNION NC-
CALDWELL MOUNTAINS-GREATER CALDWELL-BURKE MOUNTAINS-GREATER BURKE-
MCDOWELL MOUNTAINS-EASTERN MCDOWELL-RUTHERFORD MOUNTAINS-
GREATER RUTHERFORD-POLK MOUNTAINS-EASTERN POLK-OCONEE MOUNTAINS-
PICKENS MOUNTAINS-GREENVILLE MOUNTAINS-GREATER OCONEE-
GREATER PICKENS-GREATER GREENVILLE-SPARTANBURG-CHEROKEE-YORK-
ANDERSON-ABBEVILLE-LAURENS-UNION SC-CHESTER-GREENWOOD-
404 PM EDT SUN JUL 28 2013

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

.DAY ONE...TONIGHT.

AS A COLD FRONT PUSHES THROUGH THE AREA...SCATTERED THUNDERSTORMS
ARE EXPECTED TO DEVELOP INTO THIS EVENING. CLOUD TO GROUND
LIGHTNING AND BRIEF HEAVY RAINFALL ARE THE MAIN THREATS.
HOWEVER...A COUPLE OF THE STORMS MAY PRODUCE SEVERE
WEATHER...INCLUDING DAMAGING WIND GUSTS AND LARGE HAIL.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

NONE.

07

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
301 PM EDT SUN JUL 28 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0100 PM     FLOOD            CRAMERTON               35.23N 81.07W
07/28/2013                   GASTON             NC   PUBLIC

            GOAT ISLAND PARK IS FLOODED. SOCIAL MEDIA.

0220 PM     FLOOD            3 SW STANLEY            35.34N 81.13W
07/28/2013                   GASTON             NC   COUNTY OFFICIAL

            THE BRIDGE ACROSS HOYLE CREEK ON OLD WILLIS SCHOOL ROAD
            IS FLOODED. THE HIGH WATER IS LIKELY BACK WATER FLOODING
            FROM THE SOUTH FORK CATAWBA RIVER.

0220 PM     FLOOD            4 SSW IRON STATION      35.38N 81.19W
07/28/2013                   GASTON             NC   COUNTY OFFICIAL

            WATER FROM THE SOUTH FORK CATAWBA RIVER FLOODING THE
            BRIDGE NEAR THE 200 BLOCK OF HARDIN ROAD. IN
            ADDITION...LINCOLN STREET IS FLOODED.

&&

NED

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
324 PM EDT SUN JUL 28 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0310 PM     FLOOD            2 SSW LINCOLNTON        35.44N 81.26W
07/28/2013                   LINCOLN            NC   COUNTY OFFICIAL

            THE BRIDGE ACROSS THE SOUTH FORK CATAWBA RIVER ON
            LABORATORY ROAD IS FLOODED. IN ADDITION...ANDY LOGAN ROAD
            AND RIVER ROAD ARE CLOSED DUE TO FLOODING.

&&

NED

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
328 PM EDT SUN JUL 28 2013

NCZ509-510-282015-
EASTERN POLK-POLK MOUNTAINS-
328 PM EDT SUN JUL 28 2013

...A STRONG THUNDERSTORM WILL AFFECT CENTRAL POLK COUNTY THROUGH 415
PM EDT...

AT 324 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 4 MILES SOUTHWEST OF LAKE ADGER...OR 4 MILES
NORTHWEST OF COLUMBUS...MOVING EAST AT 15 MPH.

* OTHER LOCATIONS AFFECTED INCLUDE BUT ARE NOT LIMITED TO MILL
  SPRING...LAKE ADGER AND COLUMBUS.

SMALL HAIL...WIND GUSTS OF 40 TO 50 MPH AND TORRENTIAL RAIN ARE
EXPECTED WITH THIS STORM.

LAT...LON 3536 8209 3522 8209 3527 8235 3537 8228

MCAVOY

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
353 PM EDT SUN JUL 28 2013

NCZ508-510-282045-
EASTERN POLK-GREATER RUTHERFORD-
353 PM EDT SUN JUL 28 2013

...A STRONG THUNDERSTORM WILL AFFECT EASTERN POLK AND SOUTHERN
RUTHERFORD COUNTIES THROUGH 445 PM EDT...

AT 348 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 5 MILES EAST OF MILL SPRING...OR 8 MILES
SOUTHWEST OF RUTHERFORDTON...MOVING EAST AT 20 MPH.

* OTHER LOCATIONS AFFECTED INCLUDE BUT ARE NOT LIMITED TO BOSTIC...
  SPINDALE...HARRIS...FOREST CITY...ELLENBORO AND ALEXANDER MILLS.

SMALL HAIL...WIND GUSTS OF 40 TO 50 MPH AND TORRENTIAL RAIN ARE
EXPECTED WITH THIS STORM.

THE COMBINATION OF GUSTY WINDS AND WET SOIL CONDITIONS WILL CAUSE
SCATTERED TREES AND POWER LINES TO FALL. SEEK SHELTER INSIDER AN
INTERIOR ROOM.

LAT...LON 3537 8175 3521 8178 3525 8209 3536 8209

MCAVOY