Severe Thunderstorm Warning 128, NWS Greenville-Spartanburg, SC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
756 PM EDT MON JUN 24 2013

.SYNOPSIS...
A BERMUDA HIGH WILL REMAIN IN PLACE OFF THE ATLANTIC COAST THROUGH
THE WEEK...DRIVING PERSISTENT MOIST SOUTHERLY FLOW INTO THE REGION.
AFTERNOON SHOWERS AND THUNDERSTORMS WILL REMAIN A POSSIBILITY EACH
DAY. A COLD FRONT PASSAGE OVER THE WEEKEND WILL BRING AN INCREASE IN
RAIN CHANCES AND SLIGHTLY COOLER TEMPERATURES BEFORE CLEARING THE
AREA EARLY NEXT WEEK.

&&

.NEAR TERM /THROUGH TUESDAY/...
AS OF 700 PM EDT MONDAY...OUTFLOW BNDRYS ARE WORKING INTO THE
UPSTATE AND NE GA FROM THE SOUTH...TRIGGERING SOME CONVECTION IN
THEIR WAKE. THERE IS ALSO SOME ACTIVITY ALONG THE BLUE
RIDGE...ESPECIALLY UP IN NORTH CAROLINA. I TRIMMED POPS BACK ACROSS
THE WRN NC PIEDMONT AND THE ERN FOOTHILLS AND THE NE PIEDMONT OF
SOUTH CAROLINA. SINCE THESE AREAS WERE WORKED OVER BY CONVECTION
THEY SHOULD ENJOY A QUIET EVENING. HOWEVER...LATER TONIGHT WE MAY
SEE CONVECTION DEVELOP ONCE AGAIN AS THE SEA BREEZE FRONT PUSHES IN
FROM THE SOUTH BETWEEN ABOUT MIDNIGHT AND 2 AM. LAST NIGHT THIS
HELPED TO KICK OFF SHOWERS AND STORMS...AND IF SOMETHING DOESN/T
WORK OVER THE SRN PART OF THE SC/GA PARTS OF THE FA...I/D EXPECT TO
SEE SOMETHING LIKE THAT AGAIN.

AS OF 435 PM EDT MONDAY...STRONG TO SEVERE STORMS ARE CONTINUING
ALONG THE I-40 CORRIDOR OF NORTH CAROLINA. OVER THE UPSTATE..NE GA
AND MOST OF THE NC MTNS ITS GENERALLY QUIET RIGHT NOW. HOWEVER...THE
AIRMASS IS QUITE UNSTABLE OVER THIS AREA AND AS OUTFLOW BNDRYS WORK
IN FROM THE SOUTH AND WEST WE SHOULD SEE MORE DEVELOPMENT INTO THE
EARLY EVENING HOURS. THEREFORE I HAVE POPS RAMPING BACK UP INTO THE
THE HIGH CHANCE RANGE IN A COUPLE HOURS.

AS OF 225 PM EDT...COVERAGE OF SHOWERS AND THUNDERSTORMS REMAINS
FAIRLY HIGH ACROSS THE ERN HALF OF THE CWFA IN THE LOWER 70S
DEWPOINT AIR EAST OF THE MOUNTAINS. WITH SFC BASED CAPE VALUES IN
THE 2000 TO 3000 J/KG RANGE ACROSS MUCH OF THE REGION...ANTICIPATE
ADDITIONAL DEVELOPMENT ON EARLIER OUTFLOWS...AND NEW DEVELOPMENT
ACROSS THE MOUNTAINS IN WEAK BL CONVERGENCE AND LIGHT SW UPSLOPE. A
FEW SEVERE STORMS REMAIN POSSIBLE GIVEN THE INSTABILITY...BUT DCAPE
VALUES ARE GENERALLY 900 J/KG OR LESS AND PROFILES FAIRLY MOIST...SO
IT WILL TAKE VERY TALL STORMS. WILL FEATURE MAINLY SOLID CHC TO LOW
LIKELY POPS FOR THE LATE AFTN HOURS...EXCEPT CATEGORICAL ON THE ERN
FRINGE.

UPPER FORCING WILL SLOWLY IMPROVE THROUGH THE PERIOD AS H5
TROUGHINESS CONTINUES ALONG THE SRN APPALACHIANS...WITH WEAK UPPER
DIVERGENCE SETTING UP OVER THE MTNS THROUGH TUE. LOW LEVEL SW FLOW
SHOULD PROVIDE SOME UPSLOPE ENHANCEMENT IN THE SW MTNS WHERE CHC
POPS WILL BE KEPT GOING THE LONGEST TONIGHT. SIGNALS ARE MIXED ON
LOW STRATUS DEVELOPMENT TUE MORNING GIVEN A MORE SW TO W DIRECTION
IN THE BL FLOW VERSUS THE SRLY WINDS OBSERVED THIS MORNING. EXPECT
MIN TEMPS TO BE QUITE WARM. THE UPPER FORCING...PWAT IN PROFILES
AROUND 1.75 INCHES...AND A DEVELOPING LEE TROUGH SHOULD GET LIKELY
COVERAGE GOING AGAIN EARLY ON TUESDAY...WITH SIMILAR HAZARDS OF
LOCALLY HEAVY RAINFALL AND AN ISOLD SEVERE THREAT. THICKNESSES
SUPPORT VERY WARM TEMPS NEAR 90 TUE AFTN IN THE PIEDMONT...BUT CLOUD
COVER AND PRECIP SHOULD CURB THAT SOMEWHAT.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
AS OF 230 PM MONDAY...THE SHORT TERM PERIOD LOOKS RATHER
ACTIVE...HIGHLIGHTED BY A SERIES OF UPPER LEVEL IMPULSES AIDING IN
DIURNAL CONVECTION...AND AN UPPER TROF DIVING THROUGH THE OHIO
VALLEY THROUGH THE END OF THE PERIOD.  TUESDAY EVENING A PERSISTENT
BERMUDA HIGH WILL CONTINUE TO PROMOTE SOUTHERLY FLOW.  MID TO UPPER
60S DEWPOINTS AND SURFACE TEMPERATURES IN THE 80S WILL CONTINUE TO
ALLOW FOR ENOUGH INSTABILITY FOR CONVECTION INTO THE EVENING HOURS.
THUS...KEPT SOLID CHANCE POPS THROUGH SUNSET.  MEANWHILE...UPPER
LEVEL PATTERN BEGINS TO AMPLIFY SOMEWHAT AS TROF DEEPENS ACROSS THE
UPPER MIDWEST.  AS THE DISTURBANCE MOVES EASTWARD THROUGH THE
GREAT LAKES REGION ON WEDNESDAY...HEIGHTS ACROSS NORTHEAST GEORGIA
AND THE CAROLINAS WILL BEGIN TO FALL.  AS FLOW AT THE SURFACE
REMAINS SOUTHERLY...AND HEIGHTS FALL ALOFT...EXPECTING SOME RATHER
WIDESPREAD CONVECTION TO OCCUR WEDNESDAY AFTERNOON.  BOTH GFS AND
NAM FORECAST SOUNDINGS INDICATE SUBSTANTIAL DRYING IN THE MID LEVELS
INTO THE AFTERNOON HOURS THUS STEEPENING LAPSE RATES.
LIKEWISE...SBCAPE VALUES NEARING 1500-2000J/KG CANNOT BE RULED
OUT...ESPECIALLY ACROSS THE HIGHER TERRAIN AND THE UPSTATE OF SC.
KEPT HIGH END CHANCE POPS ACROSS THE ENTIRE REGION WITH SLIGHTLY
HIGHER POPS OVER THE ABOVE MENTIONED AREAS.  WITH ALL THAT
SAID...SHEAR PROFILES LOOK RATHER BLEAK AS FLOW THROUGH THE COLUMN
IS WEAK.  THUS NOT EXPECTING ANY ROTATING STORMS...LEADING TO A MORE
DAMAGING WIND...LARGE HAIL...AND HEAVY RAINFALL THREAT.  MOST IF NOT
ALL CONVECTION SHOULD CEASE BY NEAR OR SLIGHTLY AFTER SUNSET ON
WEDNESDAY EVENING AS DIURNAL HEATING IS LOST.  TEMPERATURES WILL BE
SLIGHTLY ABOVE NORMAL FOR MOST AREAS ON WEDNESDAY.

AS THE UPPER TROF DIGS OUT ACROSS THE OHIO AND TENNESSEE RIVER
VALLEYS ON THURSDAY...UPPER LEVEL HEIGHTS WILL FALL FURTHER...AND A
SURFACE COLD FRONT WILL BE MOVING CLOSER TO THE REGION.  EXPECTING
MUCH OF THE SAME ON THURSDAY AS SURFACE HEATING AND MODEST DEWPOINTS
WILL ALLOW FOR SUBSTANTIAL CAPE.  HOWEVER ALTHOUGH NOT THAT
HIGH...THURSDAY WILL YIELD MORE SHEAR THAN WEDNESDAY AS THE TROF
BASE SWINGS THROUGH...AND THE COLD FRONT APPROACHES.  THIS WILL LEAD
TO AT LEAST SOME POTENTIAL FOR BETTER CONVECTIVE ORGANIZATION.  LOOK
FOR THE MAIN THREATS ON THURSDAY TO BE DAMAGING WINDS...LARGE
HAIL...AND HEAVY RAINFALL.  CONVECTION WILL LIKELY BE MOST INTENSE
ALONG AND AHEAD OF THE FRONT DURING THE AFTERNOON HOURS.  WENT WITH
LIKELY POPS EARLY IN THE DAY ACROSS THE HIGHER TERRAIN AND SOLID
CHANCE POPS ELSEWHERE.  TEMPERATURES ON THURSDAY WILL BE AT OR
SLIGHTLY BELOW NORMAL AS THUNDERSTORM DEVELOPMENT WILL PLAY A MAJOR
ROLE.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 200 PM MONDAY...THE EXTENDED PERIOD BEGINS WITH THE CWA ON THE
FAR WESTERN PERIPHERY OF A BERMUDA HIGH AND AN UPPER LEVEL TROUGH
QUICKLY DEVELOPING OVER THE REGION ON THURSDAY. THE TROUGH DEEPENS
OVER THE WEEKEND AND TAKES OVER THE MAJORITY OF THE EASTERN
CONUS...WHILE A COLD FRONT APPROACHES WITH THE TROUGH AND THEN
STALLS OUT OVER THE AREA FOR THE WEEKEND. THE TROUGH REMAINS THE
DOMINANT FEATURE FOR MOST OF THE EXTENDED PERIOD...WITH HIGH
PRESSURE ONLY BEGINNING TO BUILD BACK IN TO THE WEST OF THE FORECAST
AREA BY EARLY NEXT WEEK. CONVECTION WILL BE MAINLY DIURNAL IN
NATURE...WITH ISOLATED TO SCATTERED COVERAGE OVER THE FOOTHILLS AND
MOUNTAINS EACH AFTERNOON. THE HIGHEST POPS WILL BE FEATURED EARLY IN
THE WEEKEND WITH THE FRONTAL PASSAGE. CLOUD COVER AND THE PERSISTENT
UPPER TROUGH WILL KEEP HIGH TEMPERATURES SLIGHTLY COOLER THAN
AVERAGE OVER THE WEEKEND...BUT NORTHWESTERLY FLOW FOLLOWING THE
FRONT WILL DRY OUT THE AIRMASS AND ALLOW A SLIGHT WARMING TREND BY
LATE WEEKEND/EARLY NEXT WEEK.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
AT KCLT...THE AIRMASS OVER THE REGION HAS BEEN WORKED THIS
EVENING...THOUGH IT IS STILL QUITE UNSTABLE JUST TO THE SOUTHWEST OF
THE AIRFIELD. THERE IS DEFINITELY A CHANCE FOR A SHOWER OR
THUNDERSTORM INTO THE EARLY MORNING HOURS. HOWEVER...WITH NO
IMMEDIATELY OBVIOUS THREAT I/M LEAVING SHRA/TSTMS OUT OF THE TAF FOR
THE OVERNIGHT HOURS...AT LEAST FOR NOW. LAST NIGHT PATCHES OF
BORDERLINE IFR/MVFR STATUS DEVELOPED OVER THE REGION NOT MUCH HAS
CHANGED TONIGHT EXCEPT THAT THE LLVL FLOW WILL BE A LITTLE MORE
VEERED. RATHER THAN CARRY A RESTRICTION I KEPT THE DAY SHIFT/S
SCT010 CIG FOR LATER TONIGHT WHICH SEEMED LIKE A REASONABLE
APPROACH. WINDS WILL BE LIGHT OUT OF THE SOUTH TONIGHT AND SSW TMRW.
THUNDERSTORMS ARE EXPECTED AGAIN TMRW AFTN AND I/VE RUN A TEMPO
GROUP FROM 18-22 UTC WHICH IS WHEN I BELIEVE CONVECTION WILL BE MOST
LIKELY.

ELSEWHERE...OUTFLOW BNDRYS COULD KICK OFF A TSTM NEAR JUST ABOUT ANY
OF THE REMAINING AIRFIELDS THIS EVENING. I HAVE CARRIED VCSH AND
CB/S FOR A FEW HOURS TO ACCOUNT FOR THIS. KAVL AND KAND PROBABLY
STAND THE BEST CHANCE. SCT TO BKN BORDERLINE MVR/IFR CIGS ARE
EXPECTED AGAIN LATER TONIGHT AND I KEPT THE DAY SHIFT/S SCT010 DECK
TO ACCOUNT FOR THIS AT THE UPSTATE SITES. KAVL WENT DOWN IN LIFR
CIGS LAST NIGHT AND WITH HIGH DEWPOINTS AND RAIN IN THE AREA THIS
EVENING THE SAME IS LIKELY LATER TONIGHT. KHKY SAW OVER AN INCH OF
RAIN AND MVFR FOG AND STRATUS IS ALSO LIKELY THERE. SCT TSTMS WILL
DEVELOP ACROSS THE REGION AGAIN TMRW AFTN. WE SHOULD SEE AS LEAST AS
MUCH COVERAGE AS TODAY AND PROB30S HAVE BEEN RETAINED
EVERYWHERE...THOUGH I DID MOVE THE PROB PERIOD BACK A FEW HOURS AT
MOST SITES.

OUTLOOK...EXPECT UNSETTLED WEATHER AT THE TERMINAL LOCATIONS THROUGH
THE WEEK...WITH UPPER TROUGHINESS PERSISTING AND THEN DEEPENING MID
TO LATE WEEK. THIS SHOULD LEAD TO MORNING FOG/STRATUS
RESTRICTIONS...WITH MAINLY AFTN/EVENING TSRA EACH DAY.

CONFIDENCE TABLE...

            00-06Z        06-12Z        12-18Z        18-24Z
KCLT       HIGH 100%     HIGH  95%     HIGH  88%     HIGH 100%
KGSP       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KAVL       HIGH  94%     MED   63%     MED   72%     HIGH  98%
KHKY       HIGH  99%     HIGH  98%     HIGH  95%     HIGH 100%
KGMU       HIGH 100%     HIGH  99%     HIGH  98%     HIGH 100%
KAND       HIGH 100%     HIGH  95%     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...VISIN
NEAR TERM...HG/MCAVOY
SHORT TERM...CDG
LONG TERM...VISIN
AVIATION...MCAVOY

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
315 PM EDT MON JUN 24 2013

GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065-
068>072-082-501>510-SCZ001>014-019-251915-
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-
315 PM EDT MON JUN 24 2013

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

.DAY ONE...THIS AFTERNOON AND TONIGHT.

NUMEROUS THUNDERSTORMS WILL CONTINUE TO DEVELOP ACROSS THE AREA THIS
AFTERNOON AND EVENING. THE STORMS WILL MOVE SLOWLY AND PRODUCE
LOCALLY HEAVY RAINFALL ALONG WITH CLOUD TO GROUND LIGHTNING. A FEW
OF THE STORMS MAY BECOME SEVERE...WITH LARGE HAIL AND DAMAGING
WIND GUSTS.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

NONE.

CDG

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>