Severe Thunderstorm Warning 154, NWS Greenville-Spartanburg, SC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
226 PM EDT WED JUN 18 2014

.SYNOPSIS...
DEEP HIGH PRESSURE AND AN ASSOCIATED UPPER LEVEL RIDGE WILL PERSIST
THROUGHOUT THE AREA THROUGH THE END OF THE WEEK. THIS WILL KEEP A
SEASONABLY WARM AIR MASS IN PLACE THROUGH THE WEEKEND. HIGH PRESSURE
WILL WEAKEN AS THE RIDGE BREAKS DOWN BY FRIDAY AFTERNOON WHICH
SHOULD YIELD A GREATER COVERAGE OF SHOWERS AND STORMS ACROSS THE
ENTIRE AREA OVER THE WEEKEND.

&&

.NEAR TERM /THROUGH THURSDAY/...
AS OF 200 PM...CONVECTION IS BLOSSOMING MORE READILY THAN YESTERDAY
ACRS THE MTNS. I UPDATED THE POP TO TRY TO MATCH TRENDS. MOST OF THE
HIGH TERRAIN LOOKS TO GET WORKED OVER BY THE CONVECTION BY SUNSET.
HOWEVER...CONFIDENCE IS STILL LOW ON HOW MUCH WILL DEVELOP ACRS THE
PIEDMONT. STORM MOTION IS VERY SLOW...AND CELLS HAVE GENERALLY
WEAKENED SO FAR AS THEY TRY TO ROLL OFF THE ESCARPMENT.
HOWEVER...THE VIS SAT IMAGERY SHOWS A CUMULUS FIELD GETTING MORE
ROBUST...WITH A COUPLE OF ISOLD STORMS DEVELOPING EAST OF CHARLOTTE.
THE 15Z-16Z HRRR RUNS ARE SHOWING A CLUSTER OF STORMS DEVELOPING
SOUTH CHARLOTTE...WITH OUTFLOW FANNING OUT AND TRIGGERING NEW CELLS
ACRS MUCH OF THE PIEDMONT LATE AFTN INTO EARLY EVENING. THE HRRR
TENDS TO BE OVERDONE...BUT IT DOES SHOW THE POTENTIAL. SO I DID
INCREASE POPS FOR PORTIONS OF THE PIEDMONT...BUT STILL GENERALLY
SLGT CHC TO LOW-END CHC. AS FOR SEVERE POTENTIAL...IT LOOKS LIKE
CELLS ARE TOPPING OUT JUST SHORT OF OBJECTIVE CRITERIA SO FAR. LAPS
CAPE ANALYSIS SHOWS 3000-4000 J/KG ACRS MUCH OF THE PIEDMONT. SO I
THINK THERE WILL BE A FEW PULSE SEVERE STORMS...WITH QUARTER-SIZE
HAIL AND/OR DAMAGING WINDS.

TONIGHT...CONVECTION SHUD WANE QUICKLY AROUND SUNSET. SIMILAR TO
LAST COUPLE NIGHTS...CLOUDS SHUD DISSIPATE AND WINDS REMAIN
CALM/LIGHT. THERE WILL BE SOME VLY FOG IN THE NC MTNS. TEMPS WILL BE
ABOVE NORMAL IN THE 60S MTNS AND UPR 60S TO LWR 70S PIEDMONT.

THURSDAY...A SHORTWAVE TROF WILL DIVE INTO THE GREAT LAKES...HELPING
WEAKEN THE LARGE UPPER RIDGE ATOP THE CWFA. HOWEVER...GUIDANCE SHOWS
ONLY SUBTLE CHANGES IN THE ENVIRONMENT FOR OUR AREA. SO EXPECT
ANOTHER HOT DAY WITH SCT-NUM AFTN SHWRS/TSTMS IN THE MTNS AND
ISOLD-SCT IN THE PIEDMONT.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
AS OF 300 PM WEDNESDAY...THE UPPER RIDGE OVER THE CAROLINAS AND GA
WILL GRADUALLY BREAK DOWN FROM THE EAST FROM THURSDAY NIGHT THROUGH
SATURDAY...AS A LOW AMPLITUDE UPPER TROUGH SETS UP OFF THE EAST
COAST. THIS WILL ALLOW A COLD FRONT TO MOVE SOUTH INTO NORTH
CAROLINAS ON THURSDAY NIGHT AND FRIDAY. THE GFS STALLS THE FRONT
NEAR THE SC BORDER ON FRIDAY NIGHT...WHILE THE NAM IS SLIGHT FARTHER
NORTH. IN ANY EVENT AN INCREASE IN CONVECTIVE ACTIVITY IS EXPECTED
WITH THE ARRIVAL OF THIS BOUNDARY. MODEL SOUNDING SHOW A BIT MORE
SHEAR BY THIS TIME...ALTHOUGH INSTABILITY IS MODEST. ALTHOUGH
STEERING FLOW IS BETTER THAN IN PREVIOUS DAYS...MOVING CELLS
ALONG...SOME CONCERN EXISTS FOR REPEAT CELLS TRAINING EAST ALONG THE
BOUNDARY RESULTING IN HEAVY RAINFALL. TEMPERATURES ARE EXPECTED TO
REMAIN ABOVE NORMAL...BUT NOT AS MUCH SO ALONG INTERSTATE 40 WHERE
CLOUD COVER WILL BE BEST ALONG THE BOUNDARY.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 115 PM EDT WEDNESDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z
ON SUNDAY WITH PERSISTENT UPPER RIDGING TO OUR WEST AND BROAD UPPER
TROFFING TO OUR NE. THE PATTERN IS EXPECTED TO FLATTEN OUT EARLY IN
THE PERIOD BEFORE ANOTHER...DEEPER UPPER TROF DIGS DOWN OVER THE
GREAT LAKES WITH THE TROF AXIS TO OUR NORTH BY THE END OF THE MEDIUM
RANGE. THE LONG RANGE MODELS DIFFER A FAIR AMOUNT WRT THE EVOLUTION
OF THE UPPER TROF WITH THE ECMWF DEVELOPING A MORE AMPLIFIED AND
COHERENT SYSTEM COMPARED TO THE GFS. THE GFS TRIES TO DEVELOP THE
TROF 1 TO 2 DAYS EARLIER AND KEEPS IT FARTHER NORTH AS IT PROGRESSES
EASTWARD. DIURNAL POPS WERE INCREASED A BIT ON BOTH MON AND TUES
NEXT WEEK TO REFLECT GENERALLY MORE MOIST GUIDANCE. OTHER THAN
THAT...NO MAJOR CHANGES WERE MADE TO THE SENSIBLE FCST.

&&

.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
AT KCLT...THE ATMOSPHERE APPEARS A BIT MORE UNSTABLE THAN THE
EARLIER GUIDANCE LED ON...BASED ON CURRENT TRENDS. NUMEROUS
SHRA/TSRA HAVE DEVELOPED ACRS THE SOUTHERN APPALACHIANS...AND THE
VIS SAT IMAGERY SHOWS CUMULUS CONGESTUS INCREASING ACRS THE CAROLINA
PIEDMONT. THE LATEST HRRR ALLOWS SEVERAL CELLS TO DEVELOP WHERE THIS
CONGESTUS IS...SO I THINK THERE WILL BE A FEW STORMS AROUND KCLT
THIS AFTN. ENUF TO WARRANT A TEMPO FOR TS. WINDS WILL BE LIGHT AND
FAVOR A SW DIRECTION...EXCEPT NEAR TS...WHERE OUTFLOWS WILL BE
VARIABLE. CONVECTION SHUD WANE QUICKLY THIS EVENING...WITH LIGHT
WINDS AND CLEARING SKIES OVERNIGHT. NOT EXPECTING MUCH FOG POTENTIAL
THURSDAY MORNING. ANOTHER ROUND OF DIURNAL SHRA/TSRA EXPECTING
SIMILAR TO LAST FEW DAYS...BUT BEYOND THE 18Z TAF PERIOD FOR KCLT.

ELSEWHERE...AS MENTIONED ABOVE...CONVECTION WILL BE MAIN CONCERN
THIS AFTN. HAVE VCTS AND TEMPO GROUPS FOR TS AT ALL SITES...GIVEN
THE SCATTERED NATURE OF STORMS. CHCS ARE STILL ONLY 20-30% FOR
DIRECT IMPACT AT MOST SITES...WITH BEST CHC AT KAVL. CONVECTION
WANES QUICKLY AFTER SUNSET. GUIDANCE SHOWING SOME FOG POTENTIAL AT
KAVL...BUT OTHERWISE...NOT ENUF CONFIDENCE TO MENTION IN THE TAFS.
WINDS WILL BE LIGHT...EXCEPT NEAR TSTMS.

OUTLOOK...ISOLATED TO SCATTERED AFTERNOON AND EVENING THUNDERSTORMS
ARE EXPECTED THROUGH THE WEEK...WITH THE GREATEST COVERAGE ACROSS
THE MTNS. RESTRICTIONS MAY OCCUR DURING TSRA AND ALSO IN THE MTN
VALLEYS EACH MORNING WHERE LOW CLOUDS AND FOG MAY FORM OVER AREAS OF
RECENT RAINFALL.

CONFIDENCE TABLE...

            18-24Z        00-06Z        06-12Z        12-18Z
KCLT       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KGSP       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KAVL       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KHKY       HIGH 100%     HIGH 100%     HIGH  91%     HIGH 100%
KGMU       HIGH 100%     HIGH 100%     HIGH 100%     HIGH 100%
KAND       HIGH 100%     HIGH 100%     HIGH  97%     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...STAARMANN
NEAR TERM...ARK
SHORT TERM...JAT
LONG TERM...JPT
AVIATION...ARK

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
314 PM EDT WED JUN 18 2014

GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065-
068>072-082-501>510-SCZ001>014-019-191915-
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-
314 PM EDT WED JUN 18 2014

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

.DAY ONE...THIS AFTERNOON AND TONIGHT.

SLOW MOVING THUNDERSTORMS WILL CONTINUE INTO THIS EVENING. THE
MAIN THREAT FROM THE THUNDERSTORMS WILL BE CLOUD TO GROUND
LIGHTNING AND HEAVY RAINFALL. A FEW OF THE STORMS COULD BECOME
SEVERE WITH DAMAGING WIND GUSTS AND LARGE HAIL.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY.

..THURSDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..FRIDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..SATURDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..SUNDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..MONDAY...NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.
..TUESDAY...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.

07

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
227 PM EDT WED JUN 18 2014

NCZ068-181915-
CLEVELAND-
227 PM EDT WED JUN 18 2014

...A STRONG THUNDERSTORM WILL AFFECT CENTRAL CLEVELAND COUNTY THROUGH
315 PM EDT...

AT 223 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR LAWNDALE...OR 8 MILES NORTH OF SHELBY...
MOVING EAST AT 5 MPH.

THIS STORM WILL IMPACT LOCATIONS NEAR...
  LAWNDALE...

SMALL HAIL...WIND GUSTS UP TO 40 MPH AND TORRENTIAL RAINFALL ARE
EXPECTED WITH THIS STORM.

DIME TO NICKEL SIZE HAIL CAN CAUSE CONSIDERABLE DAMAGE TO VEHICLES.
CONSIDER MOVING VEHICLES TO A COVERED STORAGE AREA BEFORE THE STORM
ARRIVES.

LAT...LON 3545 8147 3542 8146 3536 8141 3533 8136
      3531 8137 3530 8168 3542 8170 3548 8170
      3552 8151

07

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
247 PM EDT WED JUN 18 2014

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

0245 PM     HAIL             LEICESTER               35.65N 82.69W
06/18/2014  E1.00 INCH       BUNCOMBE           NC   PUBLIC

&&

07

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
253 PM EDT WED JUN 18 2014

NCZ505-506-508-181945-
EASTERN MCDOWELL-GREATER RUTHERFORD-MCDOWELL MOUNTAINS-
253 PM EDT WED JUN 18 2014

...A STRONG THUNDERSTORM WILL AFFECT NORTHERN RUTHERFORD AND
SOUTHEASTERN MCDOWELL COUNTIES THROUGH 345 PM EDT...

AT 253 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR THERMAL CITY...OR 11 MILES SOUTH OF
MARION...MOVING EAST AT 5 MPH.

THIS STORM WILL IMPACT LOCATIONS NEAR...
  THERMAL CITY...
  GLENWOOD...
  DYSARTSVILLE...

PENNY SIZE HAIL...WIND GUSTS UP TO 40 MPH...AND TORRENTIAL RAINFALL
ARE EXPECTED WITH THIS STORM. GUSTY WINDS CAN BLOW DOWN TREES THAT
ARE DEAD...OR THAT HAVE WEAKENED ROOT SYSTEMS. OUTDOOR FURNITURE AND
SIMILAR ITEMS CAN BE TOSSED AROUND IF NOT ANCHORED. SEEK SHELTER
INDOORS.

FREQUENT LIGHTNING IS OCCURRING WITH THIS STORM. IF OUTDOORS...TRY TO
GET INDOORS OR INTO A HARD TOPPED VEHICLE. OTHERWISE...STAY AWAY FROM
OPEN AREAS AND ISOLATED HIGH OBJECTS SUCH AS TREES. WHEN INDOORS...
STAY AWAY FROM WINDOWS AND DOORS AND AVOID USING WIRED ELECTRONIC
DEVICES. TRY TO UNPLUG UNNECESSARY APPLIANCES BEFORE THE STORM
APPROACHES.

LAT...LON 3558 8183 3558 8180 3559 8180 3559 8178
      3561 8177 3544 8173 3542 8209 3551 8211
      3553 8208 3553 8211 3560 8213 3567 8185

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
310 PM EDT WED JUN 18 2014

NCZ068-181945-
CLEVELAND-
310 PM EDT WED JUN 18 2014

...A STRONG THUNDERSTORM WILL AFFECT CLEVELAND COUNTY THROUGH 345 PM
EDT...

AT 310 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR SHELBY...MOVING SOUTHEAST AT 5 MPH.

THIS STORM WILL IMPACT LOCATIONS NEAR...
  SHELBY...

PEA SIZE HAIL...WIND GUSTS UP TO 40 MPH AND TORRENTIAL RAINFALL ARE
EXPECTED WITH THIS STORM. GUSTY WINDS CAN BLOW DOWN TREES THAT ARE
DEAD...OR THAT HAVE WEAKENED ROOT SYSTEMS. OUTDOOR FURNITURE AND
SIMILAR ITEMS CAN BE TOSSED AROUND IF NOT ANCHORED. SEEK SHELTER
INDOORS.

LAT...LON 3540 8144 3536 8141 3533 8136 3531 8137
      3528 8135 3517 8142 3517 8144 3529 8169
      3545 8159

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
314 PM EDT WED JUN 18 2014

NCZ056-504-181945-
CATAWBA-GREATER BURKE-
314 PM EDT WED JUN 18 2014

...A STRONG THUNDERSTORM WILL AFFECT EAST CENTRAL BURKE AND WESTERN
CATAWBA COUNTIES THROUGH 345 PM EDT...

AT 314 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR ICARD...OR 8 MILES WEST OF HICKORY...MOVING
EAST AT 10 MPH.

THIS STORM WILL IMPACT LOCATIONS NEAR...
  LONGVIEW...
  HICKORY...

PENNY SIZE HAIL...WIND GUSTS UP TO 40 MPH AND TORRENTIAL RAINFALL ARE
EXPECTED WITH THIS STORM. GUSTY WINDS CAN BLOW DOWN TREES THAT ARE
DEAD...OR THAT HAVE WEAKENED ROOT SYSTEMS. OUTDOOR FURNITURE AND
SIMILAR ITEMS CAN BE TOSSED AROUND IF NOT ANCHORED. SEEK SHELTER
INDOORS.

FREQUENT LIGHTNING IS OCCURRING WITH THIS STORM. IF OUTDOORS...TRY TO
GET INDOORS OR INTO A HARD TOPPED VEHICLE. OTHERWISE...STAY AWAY FROM
OPEN AREAS AND ISOLATED HIGH OBJECTS SUCH AS TREES. WHEN INDOORS...
STAY AWAY FROM WINDOWS AND DOORS AND AVOID USING WIRED ELECTRONIC
DEVICES. TRY TO UNPLUG UNNECESSARY APPLIANCES BEFORE THE STORM
APPROACHES.

LAT...LON 3580 8121 3558 8126 3565 8159 3578 8156
      3579 8145 3577 8143 3576 8138 3577 8135
      3580 8134 3580 8130 3581 8128

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
315 PM EDT WED JUN 18 2014

NCZ053-181945-
BUNCOMBE-
315 PM EDT WED JUN 18 2014

...A STRONG THUNDERSTORM WILL AFFECT EAST CENTRAL BUNCOMBE COUNTY
THROUGH 345 PM EDT...

AT 316 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR SWANNANOA...OR 10 MILES NORTHEAST OF
DOWNTOWN ASHEVILLE...MOVING EAST AT 10 MPH.

THIS STORM WILL IMPACT LOCATIONS NEAR...
  BLACK MOUNTAIN...

DIME SIZE HAIL...WIND GUSTS UP TO 40 MPH AND TORRENTIAL RAINFALL ARE
EXPECTED WITH THIS STORM. GUSTY WINDS CAN BLOW DOWN TREES THAT ARE
DEAD...OR THAT HAVE WEAKENED ROOT SYSTEMS. OUTDOOR FURNITURE AND
SIMILAR ITEMS CAN BE TOSSED AROUND IF NOT ANCHORED. SEEK SHELTER
INDOORS.

LAT...LON 3573 8231 3573 8229 3571 8228 3569 8230
      3568 8228 3565 8229 3561 8227 3559 8229
      3556 8224 3555 8221 3558 8250 3576 8249
      3576 8234

HG