Special Weather Statement, NWS Greenville-Spartanburg, SC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
252 PM EDT WED JUL 4 2012

.SYNOPSIS...
A WEAK UPPER LEVEL TROUGH OVER THE AREA WILL CONTINUE MOVING EAST
THROUGH FRIDAY. STRONG UPPER LEVEL RIDGING WILL BUILD IN FOR THE
WEEKEND AND ALLOW TEMPERATURES TO REMAIN ABOVE NORMAL WITH VARYING
COVERAGE OF AFTERNOON AND EVENING THUNDERSTORMS.

&&

.NEAR TERM /THROUGH THURSDAY/...
CONVECTION HAS FIRED OVER THE HIGH TERRAIN AS EXPECTED...AND ALONG A
LEE TROUGH/CONVERGENT AXIS ACROSS THE NC PIEDMONT. COVERAGE SHOULD
CONTINUE TO GRADUALLY EXPAND...AS MID-LEVEL SHORT WAVE TROUGH
CONTINUES TO DROP TOWARD THE REGION...SO WE CONTINUE TO FEEL GOOD
ABOUT THE 40-50 POPS COVERING MUCH OF THE AREA. INSTABILITY IS QUITE
A BIT LESS THAN YESTERDAY...OWING TO WEAKER MID-LEVEL LAPSE RATES.
THEREFORE...WE/RE NOT EXPECTING THE COVERAGE OF PULSE SEVERE STORMS
THAT WE SAW YESTERDAY. HOWEVER...LOW LEVEL SHEAR IS STRONGER THAN
YESTERDAY...SO THERE IS A CHANCE THAT CONVECTION WILL CLUSTER ALONG
COLD POOLS...AND THIS WOULD POSE A HIGHER DOWNBURST THREAT.

CONSIDERING THE EARLY START TO CONVECTION...AND THAT THE SHORT WAVE
WILL PASS SOUTH OF THE AREA THIS EVENING...COVERAGE SHOULD DIMINISH
FAIRLY QUICKLY AFTER SUNSET. THE FLOW IS EXPECTED TO VEER SOMEWHAT
TONIGHT...AS HEIGHTS BEGIN TO RISE IN THE WAKE OF THE SHORT WAVE.
THIS RETURN TO MORE NORTHERLY FLOW WILL POSE THE POTENTIAL FOR
CONVECTION ORIGINATING OVER THE GREAT LAKES REGION TO DROP TOWARD
THE AREA EARLY THURSDAY MORNING. ALTHOUGH SOME OF THE HIGH RES
MODELS HINT AT THIS OCCURRENCE...I DONT PUT A GREAT DEAL OF FAITH IN
IT...AS SHEAR IS AWFULLY WEAK EVEN THAT FAR UPSTREAM.
NEVERTHELESS... WILL INTRODUCE CHANCE POPS ACROSS THE NORTHWEST
ZONES AT THE START OF THE SECOND PERIOD.

AS THE RIDGE BEGINS TO NOSE BACK INTO THE AREA THURSDAY...FLOW ALOFT
BECOMES VERY WEAK AND TEMPS WARM A LITTLE ALOFT. MODEL CAPE VALUES
AND FORECAST SOUNDINGS ARE STILL QUITE UNSTABLE...BUT INTERESTINGLY
ENOUGH...NEITHER THE NAM NOR THE GFS GENERATE ANY CONVECTIVE PRECIP
OUTSIDE THE MTNS. WE WILL NEVERTHELESS FEATURE CHANCE POPS IN ALL
AREAS TOMORROW...BUT COVERAGE SHOULD BE LESS THAN THIS AFTERNOON.
TEMPS THROUGH THE PERIOD REMAIN AT LEAST A CATEGORY ABOVE CLIMO.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
AS OF 115 PM WEDNESDAY...UPPER HEIGHTS WILL RISE ACROSS THE EAST
FROM THE SPRAWLING RIDGE CENTERED OVER THE MIDWEST THU NIGHT THROUGH
FRI. CANNOT RULE OUT AN MCS MAKING A RUN SE FROM THE OH VALLEY FRI
MORNING...BUT THE BETTER CONVECTIVE CHANCES APPEAR TO BE DURING THE
DIURNALLY FAVORED FRI AFTN/EVENING PERIOD. SCT CONVECTIVE
DEVELOPMENT SHOULD OCCUR OVER THE MTNS EARLY FRI AFTERNOON AND THEN
OVER THE PIEDMONT LATER ON IN NRLY STEERING FLOW AND WITH LOW LEVEL
LEE TROUGH CONVERGENCE. THE NAM FEATURES SOME 4000 TO 5000 J/KG SFC
BASED CAPES FRI AFTN...BUT THIS APPEARS A BIT OVERDONE GIVEN THE NAM
SFC DEWPOINTS IN THE UPPER 70S. ALTHOUGH MID LEVEL LAPSE RATES ARE A
LITTLE LACKLUSTER GIVEN THE WARM AIRMASS...SLIGHT MID LEVEL DRYING
WILL LIKELY ENHANCE THE MICROBURST THREAT...ESPECIALLY OVER THE
PIEDMONT FRI AFTN/EVENING. TEMPS REMAIN WELL ABOVE NORMAL BUT BELOW
HEAT ADVISORY LEVELS.

THE GRADUALLY FLATTENING RIDGE WILL STRETCH ACROSS THE FORECAST AREA
THROUGH SATURDAY. WITH DRYING IN THE PROFILES FROM THE NE...THE BEST
CONVECTIVE CHANCES MAY GET SHUNTED SW TOWARD THE UPPER SAVANNAH
RIVER AREA...BUT WILL LIKELY PERSIST OVER THE HIGHER TERRAIN. SAT
AFTN MAX TEMPS SHOULD BE COMPARABLE TO FRI AFTN VALUES.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
AS OF 100 PM WEDNESDAY...NO BIG CHANGES ARE NEEDED FOR THE EXT
RANGE. THE MODELS HAVE BEEN PRETTY CONSISTENT WITH THE OVERALL
PATTERN EVOLUTION THE PAST SEVERAL RUNS. THE LATEST GEFS ENS ALSO
CONTINUES TO SHOW LITTLE SPREAD AROUND THE H5 Z MEAN. STILL
ANTICIPATE THE UPPER RIDGE TO WEAKEN AS AN EAST COAST TROF FORMS IN
RESPONSE TO -NAO BLOCKING DOWNSTREAM. THIS WILL ALLOW A SFC HIGH
ACROSS THE OH VALLEY TO BE REINFORCED AND PUSH A COLD FRONT INTO THE
REGION BY LATE MONDAY OR TUESDAY MORNING. THERE ARE TIMING
DIFFERENCES BTW THE ECMWF AND GFS WITH THE FRONTAL MOVEMENT...BUT
ONLY ABOUT 6-8 HRS BY MON NIGHT. SO...DECENT CONFIDENCE IS HAD IN
INCREASING POPS AHEAD OF THE FRONT SUN NIGHT THROUGH TUE WHEN THE
FRONT BECOMES STATIONARY ACROSS THE SRN ZONES OR NRN MIDLANDS. STILL
KEPT POPS IN THE CHANCE RANGE...BUT AT THE HIGH END MON AFTERNOON
AND EVENING MAINLY ACROSS THE HIGHER ELEVATIONS. THERE SHOULD BE
SOME ENHANCEMENT TO THE TSTM ACTIVITY WITH THE LLVL LIFT AND DEEPER
SHEAR DEVELOPING AHEAD OF THE TROF AXIS...THUS CONTINUED BOUTS OF
STRONG TO SEVERE STORMS EACH AFTERNOON IS EXPECTED. MAX TEMPS WILL
BEGIN THE PERIOD A FEW DEGREES ABOVE NORMAL SUN...THEN LOWER A
COUPLE DEGREES FOR MON AND TUE AS THE BOUNDARY HELPS INDUCES A GOOD
AMOUNT OF CLOUD COVERAGE OVER THE FA.

&&

.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
AT KCLT AND ELSEWHERE...CONVECTION IS FIRING OVER THE HIGHER TERRAIN
ONCE AGAIN THIS AFTERNOON IN A MODERATELY UNSTABLE AIR MASS. AS
CONDITIONS CONTINUE TO DESTABILIZE...COVERAGE OF CONVECTION SHOULD
INCREASE. WITH AN UPPER LEVEL DISTURBANCE CROSSING THE REGION THIS
AFTERNOON AND STRONGER FLOW ALOFT...OVERALL COVERAGE SHOULD BE A
LITTLE HIGHER THAN YESTERDAY...AND A TEMPO FOR TS HAS BEEN INCLUDED
AT KCLT BY 20Z...WITH VCTS AT ALL OTHER TERMINALS. A WEAK LEE TROUGH
CURRENTLY BISECTS THE FORECAST AREA...AND IT APPEARS THAT THIS WILL
KEEP WINDS N OR NW AT KCLT FOR THE TIME BEING...BUT A TURN TO THE W
AND SW IS POSSIBLE AS THE POSITION OF THE LEE TROUGH FLUCTUATES.
OTHERWISE...VFR CONDITIONS ARE ANTICIPATED THROUGH THE PERIOD.

OUTLOOK...ISOLATED TO SCATTERED AFTN/EVE SHRA/TSRA EXPECTED EACH DAY
THROUGH THE REST OF THE WEEK...WITH AREAS OF MORNING FOG/STRATUS
POSSIBLE...ESP IN THE MTN VALLEYS.

AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE
PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE
CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)...

WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM

&&

.CLIMATE...
RECORD HIGH TEMPERATURES THAT WILL BE APPROACHED AND POSSIBLY
EXCEEDED...

AVL
JULY 5TH 96 IN 1948
JULY 6TH 93 IN 1993

GSP
JULY 5TH 98 IN 1993
JULY 6TH 100 IN 1993

CLT
JULY 5TH 100 IN 1954
JULY 6TH 99 IN 1930

&&

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

&&

SYNOPSIS...SBK
NEAR TERM...JDL
SHORT TERM...HG
LONG TERM...SBK
AVIATION...JDL
CLIMATE...

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
256 PM EDT WED JUL 4 2012

GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065-
068>072-082-501>510-SCZ001>014-019-051900-
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-
256 PM EDT WED JUL 4 2012

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

.DAY ONE...THIS AFTERNOON AND TONIGHT.

SCATTERED THUNDERSTORMS WILL CONTINUE TO DEVELOP ACROSS THE AREA
THROUGH THIS EVENING. SOME OF THESE STORMS WILL BECOME SEVERE...WITH
THE MAIN THREAT BEING BRIEF DAMAGING WIND GUSTS AND LARGE HAIL.
LOCALLY HEAVY RAINFALL WILL ALSO BE POSSIBLE WITH SLOWER MOVING
STORMS.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH 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...OR FLASH FLOODING TO OUR OFFICE.

LANE

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
228 PM EDT WED JUL 4 2012

NCZ070-SCZ009-041915-
GASTON-YORK-
228 PM EDT WED JUL 4 2012

...A STRONG THUNDERSTORM WILL AFFECT NORTHERN YORK AND SOUTHERN
GASTON COUNTIES THROUGH 315 PM EDT...

AT 228 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 3 MILES WEST OF CROWDERS...OR 6 MILES SOUTHWEST
OF GASTONIA...MOVING SOUTH AT 5 MPH.

THIS STORM WILL BE NEAR...
  CLOVER...

DIME SIZE HAIL AND WIND GUSTS UP TO 40 MPH ARE EXPECTED WITH THIS
STORM.

LAT...LON 3498 8132 3517 8137 3517 8133 3527 8132
      3531 8118 3509 8105 3506 8106

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
233 PM EDT WED JUL 4 2012

NCZ505>508-041915-
EASTERN MCDOWELL-GREATER RUTHERFORD-MCDOWELL MOUNTAINS-RUTHERFORD
MOUNTAINS-
233 PM EDT WED JUL 4 2012

...A STRONG THUNDERSTORM WILL AFFECT NORTHWESTERN RUTHERFORD AND
SOUTHWESTERN MCDOWELL COUNTIES THROUGH 315 PM EDT...

AT 233 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 5 MILES SOUTHEAST OF OLD FORT...OR 10 MILES
SOUTHWEST OF MARION...MOVING SOUTHEAST AT 10 MPH.

THIS STORM WILL BE NEAR...
  THERMAL CITY...

PEA SIZE HAIL AND WIND GUSTS OF 30 TO 40 MPH ARE EXPECTED WITH THIS
STORM.

LAT...LON 3542 8185 3533 8205 3534 8208 3540 8213
      3541 8218 3552 8224 3553 8217 3556 8224
      3559 8228 3568 8209

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
245 PM EDT WED JUL 4 2012

NCZ503>505-041930-
BURKE MOUNTAINS-GREATER BURKE-MCDOWELL MOUNTAINS-
245 PM EDT WED JUL 4 2012

...A STRONG THUNDERSTORM WILL AFFECT NORTHEASTERN MCDOWELL AND
NORTHWESTERN BURKE COUNTIES THROUGH 330 PM EDT...

AT 245 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 4 MILES NORTHEAST OF ASHFORD...OR 9 MILES EAST OF
SPRUCE PINE...MOVING SOUTHEAST AT 10 MPH.

THIS STORM WILL BE NEAR...
  ASHFORD...

DIME SIZE HAIL...WIND GUSTS OF 30 TO 40 MPH...AND TORRENTIAL RAIN
ARE EXPECTED WITH THIS STORM.

LAT...LON 3598 8187 3595 8178 3578 8161 3565 8185
      3571 8187 3576 8194 3588 8202 3587 8200
      3589 8198 3591 8198 3592 8195 3595 8196
      3600 8189

HG

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
301 PM EDT WED JUL 04 2012

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

0210 PM     TSTM WND DMG     ETOWAH                  35.32N 82.60W
07/04/2012                   HENDERSON          NC   FIRE DEPT/RESCUE

            A TREE WAS BLOWN DOWN IN ETOWAH.

&&

MCAVOY

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
305 PM EDT WED JUL 4 2012

NCZ082-041930-
UNION-
305 PM EDT WED JUL 4 2012

...A STRONG THUNDERSTORM WILL AFFECT WESTERN UNION COUNTY THROUGH 330
PM EDT...

AT 301 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR WEDDINGTON...OR 12 MILES WEST OF MONROE...
MOVING SOUTHEAST AT 5 MPH.

* OTHER LOCATIONS AFFECTED INCLUDE BUT ARE NOT LIMITED TO MINERAL
  SPRINGS AND WEDDINGTON.

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

LAT...LON 3493 8077 3502 8081 3507 8072 3493 8062

MCAVOY

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
321 PM EDT WED JUL 4 2012

NCZ053-064-065-042000-
BUNCOMBE-HENDERSON-TRANSYLVANIA-
321 PM EDT WED JUL 4 2012

...A STRONG THUNDERSTORM WILL AFFECT NORTHEASTERN TRANSYLVANIA...
SOUTHWESTERN BUNCOMBE AND WESTERN HENDERSON COUNTIES THROUGH 400 PM
EDT...

AT 321 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 5 MILES SOUTH OF CANDLER...OR 13 MILES SOUTHWEST
OF DOWNTOWN ASHEVILLE...MOVING SOUTHEAST AT 10 MPH.

THIS STORM WILL BE NEAR...
  AVERY CREEK...
  ETOWAH...

DIME SIZE HAIL...WIND GUSTS OF 30 TO 40 MPH...AND TORRENTIAL RAIN
ARE EXPECTED WITH THIS STORM.

LAT...LON 3535 8240 3519 8264 3538 8279 3541 8274
      3543 8275 3544 8278 3547 8280 3551 8278
      3558 8269

HG