Severe Thunderstorm Warning 87, NWS Greenville-Spartanburg, SC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
200 PM EDT MON JUN 10 2013

.SYNOPSIS...
MOIST SOUTHWESTERLY FLOW WILL CONTINUE ACROSS THE AREA TODAY...AHEAD
OF A COLD FRONT WHICH WILL CROSS THE REGION TONIGHT. WARM HIGH
PRESSURE WILL BUILD IN TUESDAY AND WEDNESDAY. ANOTHER FRONT IS
EXPECTED TO MOVE ACROSS THE AREA LATE IN THE WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
LINE OF SHOWERS WITH EMBEDDED THUNDERSTORMS WILL CONTINUE TO POSE A
THREAT FOR ISOLATED SEVERE WEATHER...INCLUDING TORNADOES THROUGH THE
AFTERNOON.

AS OF 11 AM...NUMEROUS SHOWERS CONTINUE TO DEVELOP AND MOVE ACROSS
THE NC PIEDMONT THIS MORNING. FROM A CONVECTIVE STANDPOINT...WE ARE
EXPERIENCING A TROPICAL CYCLONE-LIKE ENVIRONMENT THIS MORNING...WITH
WEAK-MODERATE BUOYANCY...BUT SURPRISINGLY STRONG LOW LEVEL SHEAR
(0-1KM SHEAR MAGNITUDE OF 30 KTS...0-1KM AND EFFECTIVE HELICITY OF
AROUND 200). IN FACT...DISCRETE CELLS OVER THE PIEDMONT EARLIER THIS
MORNING EXHIBITED MINI-SUPERCELL STRUCTURES WITH PERSISTENT...ALBEIT
WEAK ROTATION. MEANWHILE...BAND OF SHOWERS ASSOCIATED WITH VORT LOBE
SWINGING SOUTHEAST OF OHIO VALLEY UPPER LOW IS BEGINNING TO MOVE
INTO THE AREA ATTM. A LEADING BAND OF DEEPER CONVECTION ACROSS NORTH
GEORGIA HAS BEEN SHOWING SIGNS OF ORGANIZATION OVER THE PAST COUPLE
OF HOURS...AND SUSPECT STRUCTURE AND SEVERE THREAT WILL IMPROVE WITH
THIS FEATURE AS IT MOVES INTO A MORE UNSTABLE AIR MASS (CAPE > 1000
J/KG) OVER THE UPSTATE/NORTHEAST GEORGIA OVER THE NEXT 1-3 HOURS.
SEVERE DOWNBURSTS WILL BE THE PRIMARY CONCERNS...BUT AN ISOLATED/
BRIEF TORNADO IS VERY POSSIBLE IN THE LOW LCL/RELATIVELY STRONGLY
SHEARED LOW LEVEL ENVIRONMENT. THERE WILL ALSO BE AN INCREASING
THREAT OF ISOLATED TORNADOES ASSOCIATED WITH PRE-LINE DISCRETE
CELLS.

THINGS GET MORE UNCERTAIN THIS EVENING AND OVERNIGHT AS THE NAM AND
4KM WRF SUGGEST ANOTHER ROUND OF STORMS...THIS TIME COMING IN FROM
THE WEST WHERE THEY WOULD DEVELOP IN THE COLDER AIR ALOFT. THE GFS
IS NOT SO ENTHUSIASTIC. THE FCST KEEPS A CHANCE POP...ESPECIALLY
OVER THE MTNS...IN DEFERENCE TO THIS. TEMPS WERE KEPT NEAR GUIDANCE.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 200 AM MONDAY...AN UPPER RIDGE WILL REMAIN ANCHORED OVER THE
SRN PLAINS THRU THE SHORT TERM...WITH RIPPLES OF SHORTWAVE
ENERGY RIDING THE FRONT SIDE OF THE RIDGE IN NWLY UPR FLOW ACRS THE
CWFA. MODELS IN AGREEMENT ON OUR AREA BEING IN THE PATH OF FAVORABLE
MCS ACTIVITY...AS A RESULT. THE QUESTION IS WHERE WILL THE MCS/S
TRACK AND AT WHAT TIMES ARE THEY MOST LIKELY TO AFFECT THE CWFA. THE
00Z NAM HAS A COUPLE OF INTERESTING MESOSCALE REFLECTIVITY
FEATURES...TAKING AN MCV SOUTH THRU THE OHIO VALLEY TUESDAY
NIGHT...AND SKIRTING THE SWRN NC MTNS AROUND DAYBREAK. THE GFS IS
SIMILAR AND THE SREF ALSO HINTS AT SOME POPS ALONG THE TN BORDER
EARLY WED MORNING. SO I HAVE INTRODUCED A SLGT CHC TO LOW-END CHC
POP IN THAT TIME FRAME IN THE NC MTNS. BEFORE THEN...FCST SNDGS LOOK
FAIRLY STABLE BEHIND THE FROPA DURING THE DAY ON TUESDAY. THE SECOND
FEATURE ON THE NAM IS ANOTHER CLUSTER OF REFLECTIVITY THAT BLOSSOMS
OVER THE SRN APPALACHIANS WEDNESDAY AFTN...WITH SOME CONVECTION
MOVING OUT INTO THE UPSTATE AND NE GA. LOOKING AT THE FCST
SNDGS...WE SHUD BECOME FAIRLY UNSTABLE...SO ANY OUTFLOW/DIFFERENTIAL
HEATING BNDRYS LEFT OVER THE FROM THE MCS MAY SPARK MORE CONVECTION.
I BUMPED UP POP A LITTLE ON WEDNESDAY AFTN AS WELL...BUT STILL BELOW
CLIMO FOR MID JUNE.

OTHERWISE...THERE IS A SURPRISING AMOUNT OF SPREAD IN THE GUIDANCE
ON MAX TEMPS ON WEDNESDAY...WITH MOS GUIDANCE TRENDING VERY WARM. I
BLENDED IN THE BIAS-CORRECTED MOS WHICH RESULTS IN A FEW LOW 90S IN
THE LWR PIEDMONT...INCLUDING NEAR 90 IN CHARLOTTE AND GREENVILLE
AREAS.

THE LATEST CYCLE OF GUIDANCE HAS TRENDED SLOWER WITH THE APPROACH OF
A SHARP SHORTWAVE TROF DIVING SE THRU THE OHIO VALLEY. IT LOOKS LIKE
WEDNESDAY NIGHT WILL BE GENERALLY DRY. SO POPS WERE LOWERED. TEMPS
WILL REMAIN ABOVE NORMAL AHEAD OF THE WAVE.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 230 AM MONDAY...NO CHANGES WERE MADE TO THE MEDIUM RANGE GRIDS
THIS MORNING. STILL EXPECTING A SHARP TROF TO DIVE THRU THE AREA ON
THURSDAY INTO THURSDAY NIGHT...ACCOMPANIED BY A COLD FRONT. POPS
RAMP UP TO A HIGH-END CHC FOR THURSDAY EVENING...THEN TAPER OFF BY
FRIDAY MORNING. THE UPR FLOW FURTHER AMPLIFIES BEHIND THE TROF...AS
IT DIGS ALONG THE EAST COAST. SO A DRY WEEKEND LOOKS ON TAP WITH
SLIGHTLY BELOW NORMAL TEMPS. TEMPS WARM BACK TO NEAR NORMAL SUNDAY.

&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AT KCLT AND KHKY...LINE OF SHOWERS AND THUNDERSTORMS WILL APPROACH
THESE AIRFIELDS BETWEEN 18Z AND 20Z...BRINGING GUSTY WINDS OF AROUND
25 KTS (MAINLY AT KCLT) AND AT LEAST BRIEF IFR VISBY. TSRA SHOULD
LAST NO LONGER THAN 2 HOURS OR SO...WITH IMPROVEMENT IN VISBY
EXPECTED THEREAFTER. MVFR CIGS WILL REMAIN POSSIBLE INTO THE
EVENING. LATE TONIGHT...WITH THE UPPER LEVELS DRYING OUT...THE
POTENTIAL WILL EXIST FOR LOW CIGS/FOG (MAYBE MORE TOWARD LOW CIGS
DUE TO PERSISTENT S/SW SURFACE WINDS AT AROUND 10 KTS). HOWEVER...WE
HAD TO LEAVE IT TO THE NEXT SHIFT TO EVALUATE.

ELSEWHERE...SHOWERS/TS WILL CONTINUE TO MOVE AWAY FROM THE TERMINALS
OVER THE NEXT HOUR OR SO...LEADING TO IMPROVING CONDITIONS IN
CIG/VISBY...ALTHOUGH MVFR CIGS MAY PERSIST INTO THE EVENING.
ADDITIONAL SHOWERS/TSTMS WILL LIKELY MOVE INTO THE FAR WESTERN NC
MTNS BY LATE THIS EVENING...BUT IT IT DIFFICULT TO SAY AT THIS POINT
HOW FAR EAST THIS ACTIVITY WILL PUSH BEFORE DISSIPATING. HAVE
GENERALLY LIMITED A VCTS MENTION TO KAVL/KHKY LATE TONIGHT. LATE
TONIGHT...WITH THE UPPER LEVELS DRYING OUT...THE POTENTIAL WILL
EXIST FOR LOW CIGS/FOG (MAYBE MORE TOWARD LOW CIGS DUE TO PERSISTENT
S/SW SURFACE WINDS AT AROUND 10 KTS). HOWEVER...WE HAD TO LEAVE IT
TO THE NEXT SHIFT TO EVALUATE.

OUTLOOK...CONDITIONS WILL IMPROVE ON TUE THROUGH MIDWEEK AS UPPER
LEVEL HIGH PRESSURE BUILDS IN. THUNDERSTORMS COULD ARRIVE FROM THE
NORTHWEST LATE WED AND AGAIN ON THU.

CONFIDENCE TABLE...

            18-24Z        00-06Z        06-12Z        12-18Z
KCLT       MED   63%     MED   78%     HIGH  87%     HIGH  94%
KGSP       MED   73%     HIGH  85%     HIGH  90%     HIGH  93%
KAVL       HIGH  98%     HIGH  98%     HIGH  86%     HIGH  91%
KHKY       MED   74%     MED   75%     LOW   57%     HIGH  87%
KGMU       MED   78%     HIGH  85%     HIGH  84%     HIGH  94%
KAND       MED   74%     HIGH  85%     HIGH  84%     HIGH  81%

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...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR GAZ010-017-
     018-026-028-029.
NC...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR NCZ033-
     035>037-048>053-056>059-062>065-068>072-082-501>510.
SC...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR SCZ001>014-
     019.

&&

SYNOPSIS...ARK
NEAR TERM...JDL/PM
SHORT TERM...ARK
LONG TERM...ARK
AVIATION...JDL

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
205 PM EDT MON JUN 10 2013

GAZ010-017-018-026-028-029-NCZ033-048>053-058-059-062>065-SCZ001-002-
004-005-010-111815-
RABUN-HABERSHAM-STEPHENS-FRANKLIN-HART-ELBERT-AVERY-MADISON-YANCEY-
MITCHELL-SWAIN-HAYWOOD-BUNCOMBE-GRAHAM-NORTHERN JACKSON-MACON-
SOUTHERN JACKSON-TRANSYLVANIA-HENDERSON-OCONEE MOUNTAINS-
PICKENS MOUNTAINS-GREATER OCONEE-GREATER PICKENS-ANDERSON-
205 PM EDT MON JUN 10 2013

...FLASH FLOOD WATCH IN EFFECT UNTIL 6 PM EDT THIS EVENING...

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

   FLASH FLOOD WATCH.

ADDITIONAL THUNDERSTORMS MAY OVER THE MOUNTAINS LATE THIS
EVENING...PRODUCING A THREAT OF CLOUD TO GROUND LIGHTNING.

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

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SKYWARN SPOTTERS ARE REQUESTED TO FORWARD ANY REPORTS OF FLASH
FLOODING TO OUR OFFICE.

NCZ035>037-056-057-068>072-082-501>510-SCZ003-006>009-011>014-019-
111815-
ALEXANDER-IREDELL-DAVIE-CATAWBA-ROWAN-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-
GREENVILLE MOUNTAINS-GREATER GREENVILLE-SPARTANBURG-CHEROKEE-YORK-
ABBEVILLE-LAURENS-UNION SC-CHESTER-GREENWOOD-
205 PM EDT MON JUN 10 2013

...FLASH FLOOD WATCH IN EFFECT UNTIL 6 PM EDT THIS EVENING...
...TORNADO WATCH 292 IN EFFECT UNTIL 10 PM EDT THIS EVENING...

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

   TORNADO WATCH.
   FLASH FLOOD WATCH.

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

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

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

LANE

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
214 PM EDT MON JUN 10 2013

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

0139 PM     TSTM WND DMG     HONEA PATH              34.45N 82.39W
06/10/2013                   ANDERSON           SC   LAW ENFORCEMENT

            TREES DOWN AT THE HIGHWAYS 76 AND 178 INTERCHANGE

&&

LG

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
216 PM EDT MON JUN 10 2013

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

0132 PM     TSTM WND DMG     2 WSW SIMPSONVILLE      34.72N 82.29W
06/10/2013                   GREENVILLE         SC   TRAINED SPOTTER

            LINES DOWN NEELY FERRY RD/WEST GEORGIA ROAD

&&

LG

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
231 PM EDT MON JUN 10 2013

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

0105 PM     TSTM WND DMG     2 SE MARIETTA           35.01N 82.47W
06/10/2013                   GREENVILLE         SC   LAW ENFORCEMENT

            TREES DOWN AT HWYS 276 AND 414

&&

LG

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
234 PM EDT MON JUN 10 2013

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

0115 PM     TSTM WND DMG     3 WNW TAYLORS           34.93N 82.37W
06/10/2013                   GREENVILLE         SC   LAW ENFORCEMENT

            TREES DOWN AT STATE PARK AND JENNIFER CT RDS

&&

LG

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
236 PM EDT MON JUN 10 2013

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

0105 PM     TSTM WND DMG     5 WNW HICKORY TAVERN    34.56N 82.27W
06/10/2013                   GREENVILLE         SC   LAW ENFORCEMENT

            TREES DOWN ON HWY 414

&&

LG

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
238 PM EDT MON JUN 10 2013

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

0118 PM     TSTM WND DMG     PIEDMONT                34.71N 82.46W
06/10/2013                   ANDERSON           SC   LAW ENFORCEMENT

            TREES DOWNN ON SALUDA DR.

&&

LG