Flash Flood in North Carolina, July 19, 2012

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
235 PM EDT THU JUL 19 2012

.SYNOPSIS...
HIGH PRESSURE WILL WEAKEN AND MOVE SOUTH TODAY. THIS WILL ALLOW
A FRONTAL BOUNDARY OVER THE OHIO VALLEY TO DROP SOUTH...INTO THE
CAROLINAS EARLY SATURDAY. THE FRONT WILL REMAIN OVER OR JUST SOUTH
OF THE REGION THROUGH THE WEEKEND AND DISSIPATE ON MONDAY.

&&

.NEAR TERM /THROUGH FRIDAY/...
AT 230 PM EDT THURSDAY...AN UPPER TROUGH WILL AMPLIFY ALONG THE EAST
COAST TONIGHT AND FRIDAY. A WEAK IMPULSE REACHING THE BASE OF THE
TROUGH IS EXPECTED TO SUPPORT INCREASED CONVECTIVE COVER THIS
AFTERNOON AND EVENING...IN A MOIST UNSTABLE AIR MASS THAT WILL
SUPPORT PULSE SEVERE THUNDERSTORMS WITH LARGE HAIL AND DAMAGING
WIND. STEERING FLOW WILL NOT BE AS WEAK AS EARLIER THIS
WEEK...LIMITING RAINFALL ACCUMULATIONS. CONVECTION WILL GRADUALLY
DIMINISH THIS EVENING WITH THE LOSS OF HEATING. MODEL GUIDANCE
SUGGEST THAT FOG CAN BE EXPECTED ACROSS MUCH OF OF THE AREA BY
DAYBREAK...BUT ONLY FEW MOUNTAIN VALLEYS ARE EXPECTED OT HAVE DENSE
FOG. MINIMUM TEMPERATURES WILL SLIGHTLY ABOVE NORMAL IN A MOIST AIR
MASS UNDER CLOUDS.

A COLD FRONT WILL APPROACH FROM THE NORTH ON FRIDAY...WHILE A PAIR
OF SHORTWAVES MOVES INTO THE BASE OF THE TROUGH. POPS AND QPF WILL
BE SIGNIFICANTLY HIGHER ON FRIDAY IN ADVANCE OF THE FRONT.
INSTABILITY WILL BE SUFFICIENT FOR SEVERE THUNDERSTORMS AGAIN...AND
WITH UNIDIRECTIONAL SHEAR PRESENT...SOME ORGANIZATION IS POSSIBLE...
ESPECIALLY IN THE PIEDMONT. WITH BETTER STEERING FLOW AND MOVING
STORMS...ANY HEAVY PRECIPITATION AMOUNTS WOULD BE FROM TRAINING OR
REPEATING CELLS. MAXIMUM TEMPERATURES WILL BE NEAR NORMAL...AS
ENOUGH BREAK IN CLOUD COVER WILL PERMIT HEATING TO OCCUR.

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
AS OF 235 PM THURSDAY...SHORT WAVE TROF WITH A SERIES OF ENERGY
MAXES REMAINS OVER THE AREA FRI NITE AND SAT. SFC COLD FRONT BECOMES
STALLED ACROSS THE AREA AS WELL. THE ENERGY MAXES AND RIGHT ENTRANCE
REGION OF THE UPPER JET WILL PROVIDE SOME SYNOPTIC SCALE FORCING AND
UPPER DIVERGENCE WHILE THE FRONT PROVIDES LOW LEVEL CONVERGENCE.
STILL EXPECT A DIURNAL TREND TO THE CONVECTION...BUT THE COPIOUS
MOISTURE AND LARGE SCALE FORCING SHUD KEEP AT LEAST SOME ACTIVITY
GOING MUCH OF THE NIGHT FRI NITE. NUMEROUS COVERAGE IS EXPECTED
AGAIN FOR SATURDAY FOR THE SAME REASONS...AS IS THE LINGERING
COVERAGE OVERNIGHT. HOWEVER...AREAS OUTSIDE OF THE WRN MOUNTAINS
COULD SEE BETTER COVERAGE. LOWS WILL BE NEAR NORMAL...BUT HIGHS WILL
BE BELOW NORMAL WITH MORE CLOUDS EARLIER PRECIP ONSET.

THE SHORT WAVE TROF MOVES EAST OF THE AREA SUNDAY...BUT A SHEAR AXIS
WILL REMAIN IN ITS PLACE. THE FRONT WILL BEGIN TO WASH OUT...BUT A
WEAK BOUNDARY WILL LIKELY LINGER. LOOKS LIKE COVERAGE COULD BE A
LITTLE LESS THAN SATURDAY WITH LESS UPPER SUPPORT...BUT SHUD BE AT
LEAST SCT. LOWS WILL BE A TAD COOLER...BUT HIGHS SHUD REBOUND TO
JUST BELOW NORMAL.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
AS OF 215 PM THURSDAY...A WEAK TROF WILL KEEP A SPLIT OVER THE AREA
BETWEEN THE WEST-CENTRAL CONUS RIDGE AND THE BERMUDA RIDGE. AT THE
SFC...A LEE TROF AND COPIOUS LOW LEVEL MOISTURE WILL BE OVER THE
AREA. THIS WILL LEAD TO SCT DIURNAL TSRA AND NEAR TO SLIGHTLY ABOVE
NORMAL TEMPS. ON TUE AND WED...SHORT WAVES MOVING THRU THE NRN
STREAM FLOW HELP CARVE OUT AN UPPER TROF OVER THE EAST COAST. AT THE
SFC...LOW LEVEL MOISTURE AND THE LEE TROF REMAIN IN PLACE FOR TUE
WHILE A BACK DOOR COLD FRONT APPROACHES ON WED. AGAIN...GIVEN THE
MOISTURE...INSTABILITY AND WEAK FORCING...GENERALLY SCT DIURNAL
CONVECTION IS EXPECTED BOTH DAYS. TEMPS WILL INCREASE TO ABOVE
NORMAL BY WED. THE TROF MOVES OFF THE COAST THU AND RIDGING BEGINS
TO REASSERT ITSELF OVER THE SERN US AS MORE SHORT WAVE ENERGY MOVES
ACROSS THE NRN TIER OF THE COUNTRY. THE BACK DOOR FRONT MOVES NORTH
AWAY FROM THE AREA AS WELL. STILL EXPECT ENUF MOISTURE AND
INSTABILITY TO LINGER FOR SCT DIURNAL CONVECTION ONCE AGAIN. TEMPS
WILL FALL A DEGREE OR TWO FOR THU.

&&

.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
AT KCLT...CONVECTION SHOULD HAVE GREATER COVERAGE TODAY AS A WEAK
UPPER IMPULSE MOVES INTO THE AREA. A TEMPO FOR GUSTY WINDS...MVFR
VSBY AND LOW VFR CIG WILL BE CARRIED FOR SEVERAL HOURS THIS
AFTERNOON. GUIDANCE AND TRENDS FAVOR MVFR FOG AROUND DAYBREAK
FRIDAY. GUIDANCE SUPPORTS A VFR CIG...BUT SOME SCATTERED VERY LOW
CLOUDS WILL BE CARRIED IN THE TAF. PRECIPITATION ASSOCIATED WITH AN
APPROACHING COLD FRONT ON FRIDAY SHOULD NOT BE A FACTOR UNTIL AFTER
THIS FORECAST PERIOD.

ELSEWHERE...CONVECTION IS ALREADY FIRING IN THE MOUNTAINS...BUT IS
EXPECTED OT SPREAD INTO THE FOOTHILLS...AND ALL SITES WILL GET A
TEMPO FOR MVFR CONDITIONS IN THUNDERSTORMS THIS AFTERNOON. GUIDANCE
AND RECENT TRENDS FAVOR FOG RETRACTIONS AT DAYBREAK FRIDAY...IFR AT
KAVL...AND MVFR IN THE FOOTHILLS. GUIDANCE FAVORS VFR DAYBREAK CIGS
AT TAF SITES...BUT TRENDS WOULD FAVOR A RESTRICTION AT KAVL...AND AN
IFR CIG WILL BE CARRIED THERE. CONVECTION IS EXPECTED TO GET GOING
EARLIER ON FRIDAY AS A COLD FRONT ARRIVES...BUT ONLY KAVL WILL HAVE
ENOUGH COVERAGE BEFORE THE END OF THE FORECAST PERIOD TO CARRY
THUNDER.

OUTLOOK...PRECIPITATION AND ASSOCIATED RESTRICTIONS REMAIN POSSIBLE
THROUGH THE WEEKEND. FOG AND STRATUS CHANCE WILL BE GREATEST IN THE
MORNING...ESPECIALLY 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

&&

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

&&

SYNOPSIS...PAT
NEAR TERM...JAT
SHORT TERM...RWH
LONG TERM...RWH
AVIATION...JAT

HAZARDOUS WEATHER OUTLOOK...CORRECTED
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
447 AM EDT THU JUL 19 2012

GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065-
068>072-082-501>510-SCZ001>014-019-200900-
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-
447 AM EDT THU JUL 19 2012

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

.DAY ONE...TODAY AND TONIGHT.

NUMEROUS THUNDERSTORMS WILL DEVELOP ACROSS THE WESTERN CAROLINAS
AND NORTHEAST GEORGIA AGAIN TODAY. THE STORMS ARE EXPECTED TO
INITIALLY DEVELOP ACROSS THE MOUNTAINS...THEN SPREAD INTO THE
FOOTHILLS AND PIEDMONT LATER IN AFTERNOON.

SEVERAL OF THE STORMS TODAY COULD BECOME SEVERE...PRODUCING AREAS
OF WIND DAMAGE AND LARGE HAIL. THE EFFECTS OF HEAVY DOWNPOURS AND
SATURATED SOILS WILL ENHANCE THE THREAT OF FALLING TREES. LOCALLY
VERY HEAVY RAINFALL WILL ACCOMPANY THE STORMS AND FLOODING OF POOR
DRAINAGE AREAS AND A FEW STREAMS MAY DEVELOP. THE STORMS WILL ALSO
PRODUCE FREQUENT CLOUD TO GROUND LIGHTNING.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

NONE.

14

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
435 PM EDT THU JUL 19 2012

NCZ037-057-192100-
DAVIE-ROWAN-
435 PM EDT THU JUL 19 2012

...A STRONG THUNDERSTORM WILL AFFECT NORTHWESTERN ROWAN AND
SOUTHEASTERN DAVIE COUNTIES THROUGH 500 PM EDT...

AT 435 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR CLEVELAND...OR 11 MILES NORTHWEST OF
SALISBURY...MOVING EAST AT 10 MPH.

THIS STORM WILL IMPACT LOCATIONS NEAR...
  COOLEEMEE...

PEA SIZE HAIL...WIND GUSTS UP TO 40 MPH...AND TORRENTIAL RAIN ARE
EXPECTED WITH THIS STORM.

LAT...LON 3563 8040 3565 8076 3571 8076 3583 8072
      3585 8040 3584 8040 3585 8041 3583 8043
      3582 8047 3579 8047 3577 8045 3574 8045
      3572 8040

HG

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
441 PM EDT THU JUL 19 2012

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

0407 PM     TSTM WND DMG     1 SW STATESVILLE        35.78N 80.90W
07/19/2012                   IREDELL            NC   911 CALL CENTER

            TREE DOWN ON SHED AT HILL STREET

&&

RWH

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
442 PM EDT THU JUL 19 2012

SCZ010-192115-
ANDERSON-
442 PM EDT THU JUL 19 2012

...A STRONG THUNDERSTORM WILL AFFECT NORTHERN ANDERSON COUNTY THROUGH
515 PM EDT...

AT 442 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR PENDLETON...OR 3 MILES SOUTHEAST OF
CLEMSON...MOVING SOUTHEAST AT 10 MPH.

THIS STORM WILL IMPACT LOCATIONS NEAR...
  SANDY SPRINGS...

PEA SIZE HAIL...WIND GUSTS UP TO 40 MPH...AND TORRENTIAL RAIN ARE
EXPECTED WITH THIS STORM.

LAT...LON 3446 8262 3460 8286 3467 8279 3473 8267
      3465 8248

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
443 PM EDT THU JUL 19 2012

NCZ051-052-059-192115-
HAYWOOD-NORTHERN JACKSON-SWAIN-
443 PM EDT THU JUL 19 2012

...A STRONG THUNDERSTORM WILL AFFECT CENTRAL HAYWOOD...NORTHEASTERN
SWAIN AND NORTHERN JACKSON COUNTIES THROUGH 515 PM EDT...

AT 443 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 6 MILES NORTHWEST OF MAGGIE VALLEY...OR 12 MILES
NORTHWEST OF WAYNESVILLE...MOVING SOUTHEAST AT 10 MPH.

THIS STORM WILL IMPACT LOCATIONS NEAR...
  MAGGIE VALLEY...

PEA SIZE HAIL...WIND GUSTS UP TO 40 MPH...AND TORRENTIAL RAIN ARE
EXPECTED WITH THIS STORM.

LAT...LON 3550 8291 3536 8313 3559 8331 3570 8314

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
449 PM EDT THU JUL 19 2012

NCZ036-056-192115-
CATAWBA-IREDELL-
449 PM EDT THU JUL 19 2012

...A STRONG THUNDERSTORM WILL AFFECT SOUTHEASTERN CATAWBA AND
SOUTHERN IREDELL COUNTIES THROUGH 515 PM EDT...

AT 450 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR TERRELL...OR 13 MILES SOUTHWEST OF
STATESVILLE...MOVING EAST AT 5 MPH.

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

LAT...LON 3550 8079 3552 8090 3551 8092 3551 8096
      3553 8096 3553 8094 3555 8096 3555 8109
      3572 8107 3570 8076

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
455 PM EDT THU JUL 19 2012

NCZ052-053-064-065-192130-
BUNCOMBE-HAYWOOD-HENDERSON-TRANSYLVANIA-
455 PM EDT THU JUL 19 2012

...A STRONG THUNDERSTORM WILL AFFECT EASTERN HAYWOOD...NORTHEASTERN
TRANSYLVANIA...NORTHWESTERN HENDERSON AND SOUTHWESTERN BUNCOMBE
COUNTIES THROUGH 530 PM EDT...

AT 455 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 4 MILES NORTHEAST OF CRUSO...OR 13 MILES EAST OF
WAYNESVILLE...MOVING SOUTHEAST AT 15 MPH.

THIS STORM WILL IMPACT LOCATIONS NEAR...
  ETOWAH...

PEA SIZE HAIL...WIND GUSTS UP TO 40 MPH...AND TORRENTIAL RAIN ARE
EXPECTED WITH THIS STORM.

LAT...LON 3543 8247 3525 8263 3544 8291 3558 8278

HG