Severe Thunderstorm Warning 219, NWS Greenville-Spartanburg, SC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
754 PM EDT FRI JUL 12 2013

.SYNOPSIS...
ABUNDANT TROPICAL MOISTURE WILL RETURN TO THE AREA THIS
WEEKEND...ALLOWING SHOWERS AND THUNDERSTORMS TO DEVELOP EACH
AFTERNOON. HIGH PRESSURE WILL BUILD IN MONDAY AND PERSIST THROUGH
THE END OF NEXT WEEK.

&&

.NEAR TERM /THROUGH SATURDAY/...
AS OF 745 PM EDT...THE HRRR MESOSCALE MODEL HAS BEEN FAIRLY ACCURATE
THIS EVENING IN DEPICTING THE LOCATION OF CONVECTION ALONG THE ERN
SLOPES OF THE HIGHER TERRAIN AND ALONG OUTFLOW BOUNDARIES. IT NOW
HAS ADDITIONAL CONVECTION OVER THE NRN NC MTNS SLIDING SOUTHWARD
ALONG THE BLUE RIDGE AND THE IMMEDIATELY ADJACENT FOOTHILLS THROUGH
MIDNIGHT...AND THIS SOLUTION WILL BE ACCEPTED. COVERAGE AND
INTENSITY ACROSS THE SRN TIER WILL CONTINUE TO WANE WITH THE LOSS OF
HEATING AND GIVEN THAT MOST OF THE AREA HAS BEEN WORKED OVER. WILL
NOT BE ABLE TO COMPLETELY LET GO OF ISOLD TO SCT SHOWERS OVERNIGHT
AS THE BL REMAINS MOIST AND AN EASTERLY COMPONENT TO THE LOW LEVEL
FLOW WILL PERSIST. ANTICIPATE FAIRLY WIDESPREAD LOW CLOUDS AND AND
PATCHY TO AREAS OF FOG TOWARD OVERNIGHT.

THE UPPER LOW WILL RETROGRADE TO THE MS VALLEY SAT...WHILE AT THE
SFC AN INVERTED TROF WILL MOVE INTO THE AREA FROM THE COAST. THIS
WILL KEEP LOW LEVEL SELY UPSLOPE FLOW ACROSS IN PLACE THROUGH THE
DAY WITH CONTINUED COPIOUS LOW LEVEL MOISTURE. THE NAM IS ALONE IN
KEEPING DEEP MOISTURE OUT OF THE AREA WITH THIS SYSTEM...SO HAVE
FOLLOWED THE TRENDS OF THE OTHER GUIDANCE AND INCREASED POP TO
LIKELY OUTSIDE OF THE MTNS BY AFTERNOON. THERE WILL BE ENOUGH
INSTABILITY FOR THUNDERSTORMS TO DEVELOP...BUT SEVERE TSTMS WILL BE
LESS LIKELY AS THE COOL AND DRY MID LEVELS MOVE WEST WITH THE UPPER
LOW. FOR NOW...THE QPF FORECAST DOES NOT SUGGEST WIDESPREAD FLOOD
POTENTIAL DURING THE DAY SAT. THEREFORE...WILL NOT ISSUE A WATCH
ATTM...BUT LATER SHIFTS WILL NEED TO EVALUATE THE POTENTIAL.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
AS OF MIDDAY FRI...ATLANTIC MOISTURE WILL HAVE SPREAD ACROSS THE CWFA
BY THE START OF THE PERIOD IN THE WAKE OF WARM FRONT. MODEST E TO SE
LLVL FLOW WILL BE UNDERWAY AT THAT TIME AND CONTINUE THROUGH THE END
OF THE PERIOD. THIS UPSLOPE FLOW WILL PROVIDE AT LEAST WEAK FORCING
WITH THE MAIN EFFECT TO ENHANCE THE COVERAGE OF ALREADY DIURNALLY
DRIVEN CONVECTION.

THE INITIAL WAVE OF MOISTURE AS SHOWN BY A PLUME OF PWATS NEAR 2
INCHES CROSSES THE CWFA SATURDAY NIGHT INTO SUNDAY MORNING...BUT
DIMINISHES SOMEWHAT AS THE PLUME MOVES INLAND. SATURATED LAYER ON
PROG SOUNDINGS REMAINS SOMEWHAT SHALLOW WITH BEST LOOKING SOUNDINGS
IN THIS REGARD COMING FROM THE MTNS/FOOTHILLS. WEAK NEAR-SFC
INSTABILITY IS SEEN THOUGH...AND INDEED THE NAM PRECIP SHOWN SAT
NIGHT IS ALL CONVECTIVE. CLOUD LAYER FLOW LOOKS STRONG ENOUGH AT THIS
TIME TO LIMIT...BUT NOT TOTALLY ELIMINATE...THE FLASH FLOOD THREAT.
GOING FURTHER INTO THE DAY ON SUNDAY SOME DRYING OCCURS AND PWATS
LOWER CLOSER TO CLIMO. DESPITE THE RELATIVE LACK OF MOISTURE...CAPE
VALUES OF 2000 J OR MORE ARE SHOWN ON THE NAM /1000 OR MORE ON GFS/
SO SOME VIGOROUS CONVECTION COULD DEVELOP. SHEAR WILL CONTINUE TO BE
WEAK BUT STORM MOTIONS FAIRLY SLOW...THUS MORE OF THE SAME CONCERNS
IN THAT REGARD BUT PERHAPS WITH MORE CONCERN FOR SVR WX.

HIGH PRESSURE BUILDS IN SUN NIGHT SOMEWHAT DISRUPTING THE LLVL FLOW
ON THE GFS/NAM DEPICTION OF THE FEATURE...AND CONTINUING TO DRY THE
ATMOSPHERE. A WEAK MIDLEVEL SUBSIDENCE INVERSION DEVELOPS BUT SOME
PROG SOUNDINGS STILL SHOW VERY WEAK INSTABILITY DESPITE A REFLECTION
OF THE SUBSIDENCE. THUS HUNG ON TO VERY LOW BUT MENTIONABLE POPS THRU
THE NIGHT...SLIGHTLY HIGHER WEST WHERE THE BEST LLVL MOISTURE
REMAINS. ON MONDAY WARM MIDLEVELS APPEAR TO CONTINUE TO STIFLE
CONVECTION PARTICULARLY TOWARD THE NORTH NEARER THE CENTER OF THE
HIGH.

WITH THE REGION COMING BACK INTO A MORE TYPICAL PATTERN DOMINATED BY
ATLANTIC HIGH PRESSURE...TEMPERATURES SHOULD MODERATE TO NEAR NORMAL
DURING THE PERIOD...REMAINING SLIGHTLY BELOW NORMAL GIVEN THE MORE
NORTHWARD THAN USUAL POSITION OF THE HIGH.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 130 PM FRIDAY...THE OVERALL PATTERN HAS BECOME DRIER IN THE
LATEST OP MODEL RUNS. THE 12Z GFS IS STILL A MOISTER MODEL WITH THE
UPSLOPE FLOW...WHILE THE ECWMF KEEPS LLVL LAYERED RH THE RATHER LOW.
IN ANY CASE...A DEEP SUB INVERSION WILL BE IN PLACE THROUGH MOST OF
THE PERIOD ASSOCIATED WITH THE ANOMALOUS STACKED HIGH. THUS...SCF
BASED PARCELS WILL HAVE A GOOD AMOUNT OF CIN TO OVERCOME WITH NO
DEFINED KICKER...HOWEVER SOME MODERATE ELCAPE WILL BE AVAILABLE AND
AREAS UNDER DIFFERENTIAL HEATING SHOULD SPAWN ISOL AFTERNOON PULSE
STORMS. THE CLIMO POP IS ADHERED TO ACROSS THE MTNS AS WELL...WITH
NE/LY TO E/LY MECH LIFT PROVIDING THE ADDED FACTOR FOR SCT AFTERNOON
CONVECTION. PWATS WILL REMAIN RELATIVELY LOW...YET INCREASE AS THE
PERIOD PROGRESSES IN A MORE DEFINED AND CONTINUOUS SW/LY LLVL FLOW
ASSOCIATED WITH A DEVELOPING AND NORMALLY PLACED BERMUDA HIGH. MAX
TEMPS WILL RESPOND IN THE DRIER ENVIRONMENT AND A RETURN TO NEAR
NORMAL LEVELS IS EXPECTED THROUGH THE PERIOD. NORMAL MIN TEMPS WILL
ALSO PERSIST AS EVENING CONVECTIVE CLOUDS DISSIPATE AND ALLOW GOOD
RADIATIONAL COOL CONDS.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
AT KCLT...THE VICINITY REMAINS LARGELY EXEMPT FROM CONVECTION THIS
EVENING...WITH NEW DEVELOPMENT OCCURRING MAINLY WELL S AND W OF THE
AIRFIELD. WILL CONTINUE THE MENTION OF VCSH FOR A POSSIBLE ROGUE
SHOWER...WITH VFR CIGS THROUGH THE LATE EVENING HOURS. ANTICIPATE A
RETURN TO MVFR AND THEN IFR STRATUS OVERNIGHT WITH CONTINUED HIGH
LEVELS OF BOUNDARY LAYER MOISTURE. THERE SHOULD BE SLOW IMPROVEMENT
TO MVFR THROUGH THE MORNING HOURS ON SATURDAY. NE WINDS CONTINUE
THROUGH THE PERIOD WITH OCCASIONAL GUSTS...AND SHRA/TSRA POSSIBLY
REDEVELOPING DURING THE AFTN HOURS...WHERE A PROB GROUP WILL BE USED.

ELSEWHERE...CONVECTION HAS FINALLY WEAKENED AND DIMINISHED IN
COVERAGE ACROSS THE UPSTATE...BUT ISOLD TSTMS COULD STILL THREATEN
KGMU AND KAND THROUGH THE EVENING HOURS. ADDITIONAL SLOW MOVING
STORMS NEAR THE BLUE RIDGE ARE STAYING AWAY FROM KAVL AND KHKY THUS
FAR...BUT VCTS WILL BE NEEDED AS THESE SLIP SSW ALONG THE ERN SLOPES
THROUGH 04Z. ANTICIPATE COVERAGE DIMINISHING OVERNIGHT...BUT WITH
ROGUE -SHRA POSSIBLE IN ANY UPSLOPE MOISTURE. ANTICIPATE SOLID IFR
CIGS THROUGH DAYBREAK...IMPROVING THROUGH MVFR INTO EARLY
AFTERNOON...WITH SHRA/TSRA REDEVELOPING SAT AFTN. EXPECT MAINLY NE
WINDS AWAY FROM ANY TSTMS.

OUTLOOK...A TROUGH OF LOW PRESSURE WILL MOVE INLAND FROM THE COAST
OVER THE WEEKEND. LOW LEVEL MOISTURE WILL PERSIST...CONTINUING THE
RISK OF SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS ACROSS THE
AREA...ALONG WITH MORNING FOG/LOW CLOUDS. HIGH PRESSURE WILL BUILD
OVER THE REGION THROUGH NEXT WEEK...WITH SCATTERED AFTERNOON AND
EVENING THUNDERSTORMS POSSIBLE.

CONFIDENCE TABLE...

            00-06Z        06-12Z        12-18Z        18-24Z
KCLT       MED   76%     MED   79%     MED   77%     HIGH  87%
KGSP       HIGH  91%     MED   73%     MED   75%     HIGH 100%
KAVL       HIGH  85%     MED   76%     HIGH  82%     HIGH  90%
KHKY       HIGH  90%     MED   76%     MED   74%     HIGH  83%
KGMU       HIGH 100%     MED   73%     MED   75%     HIGH 100%
KAND       HIGH 100%     LOW   49%     MED   78%     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...SBK
NEAR TERM...HG/RWH
SHORT TERM...WIMBERLEY
LONG TERM...SBK
AVIATION...HG

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
537 PM EDT FRI JUL 12 2013

GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065-
068>072-082-501>510-SCZ001>014-019-132145-
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-
537 PM EDT FRI JUL 12 2013

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

.DAY ONE...TONIGHT.

SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL CONTINUE THIS
AFTERNOON AND INTO TONIGHT. A FEW STORMS WILL BE SEVERE...WITH THE
POTENTIAL TO PRODUCE LARGE HAIL AND DAMAGING WINDS. HEAVY RAINFALL
AND ISOLATED FLOODING WILL REMAIN A THREAT WITH ANY STORMS THAT
DEVELOP...AS STORMS WILL BE SLOW MOVING AND THE GROUND IS
SATURATED ACROSS MUCH OF THE AREA.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.

SCATTERED TO WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED
THROUGH SUNDAY...WITH TROPICAL MOISTURE RETURNING FROM THE EAST.
HEAVY RAINFALL AND ISOLATED FLOODING WILL REMAIN A THREAT.

.SPOTTER INFORMATION STATEMENT...

SKYWARN SPOTTERS ARE REQUESTED TO FORWARD ANY REPORTS OF LARGE
HAIL...DAMAGING WINDS...OR FLASH FLOODING TO OUR OFFICE.

HG

<!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>

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1013 PM EDT FRI JUL 12 2013

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

1005 PM     HAIL             5 WSW MORGANTON         35.71N 81.78W
07/11/2013  M1.00 INCH       BURKE              NC   TRAINED SPOTTER

            OBSERVED ALONG CAUSBY ROAD IN GLEN ALPINE

&&

CSH

PRELIMINARY LOCAL STORM REPORT...CORRECTED
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1022 PM EDT FRI JUL 12 2013

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

1005 PM     HAIL             5 WSW MORGANTON         35.71N 81.78W
07/12/2013  M1.00 INCH       BURKE              NC   TRAINED SPOTTER

            OBSERVED ALONG CAUSBY ROAD IN GLEN ALPINE

&&

CSH

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1024 PM EDT FRI JUL 12 2013

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

1020 PM     HAIL             MORGANTON               35.74N 81.70W
07/12/2013  E1.00 INCH       BURKE              NC   PUBLIC

            PUBLIC REPORT OF QUARTER SIZE HAIL.

&&

HG