Flash Flood Warning 7, NWS Greenville-Spartanburg, SC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
756 PM EDT THU MAY 14 2009

.SYNOPSIS...
HIGH PRESSURE WILL MOVE EAST ACROSS THE ATLANTIC OCEAN FRIDAY AND
SATURDAY...ALLOWING MOISTURE TO RETURN FROM THE GULF OF MEXICO AHEAD
OF AN APPROACHING COLD FRONT. THE FRONT IS EXPECTED TO MOVE IN FROM
THE WEST SUNDAY AND MAY LINGER ACROSS THE CAROLINAS INTO MONDAY.

&&

.NEAR TERM /THROUGH FRIDAY/...
DEEP MOISTURE BAND ASSOCIATED WITH WEAKENING FRONTAL ZONE WILL MOVE
INTO THE NC MTNS BY EARLY EVENING. THIS COMBINED WITH A MODERATE
DEGREE OF INSTABILITY SHOULD RESULT IN SCATTERED CONVECTIVE
DEVELOPMENT ACROSS THE HIGHER TERRAIN THIS EVENING. WITH THE BAND OF
MOISTURE REMAINING OVER WESTERN SECTIONS OF THE CWFA...AT LEAST
SLIGHT CHANCE POPS WILL BE CARRIED THROUGH THE OVERNIGHT ACROSS THE
MTNS.

THE FRONT WILL DISSIPATE OVER THE SOUTHEAST ON FRIDAY...ALTHOUGH
MOISTURE WILL REMAIN ENSCONCED ACROSS THE AREA. IN FACT...A
DEEPENING SOUTHEAST FLOW WILL ACTUALLY ALLOW FOR AN INCREASE IN
ATLANTIC MOISTURE ACROSS THE CAROLINAS. IN ADDITION...MODEL
SOLUTIONS AGREE THAT MODERATE DESTABILIZATION WILL OCCUR FRIDAY
AFTERNOON. THIS IS EXPECTED TO RESULT IN AT LEAST SCATTERED DIURNAL
CONVECTION ACROSS THE AREA...WITH THE HIGHEST POPS EXISTING ACROSS
THE MTNS...PARTICULARLY THE SOUTHERN ESCARPMENT.

&&

.SHORT TERM /FRIDAY NIGHT THROUGH MONDAY/...
AS OF 230 PM THURSDAY...WARM...MOIST AND UNSTABLE AIR MASS REMAINS
IN PLACE FRI NITE AND SATURDAY. HIGHEST POP CHANCES WILL BE MAINLY
DIURNAL. HOWEVER...WITH THE VERY MOIST AND WEAKLY UNSTABLE AIR MASS
AND SELY FLOW...CONVECTION WILL LINGER/FIRE DURING THE NON-DIURNAL
TIMES AS WELL. DISREGARDED THE VERY LOW CAPE ON THE OPS NAM GIVEN
THE MODERATE INSTABILITY SEEN ON THE OPS GFS AND THE SREF. SHEAR
WILL BE VERY WEAK THOUGH...SO HEAVY RAINFALL A POSSIBILITY WITH SLOW
MOVING STORMS. FOLLOWED A GUIDANCE BLEND FOR TEMPS.

COLD FRONT MOVES INTO THE AREA SAT NITE AND THRU THE AREA SUNDAY.
POP INCREASES INTO AT LEAST THE LIKELY RANGE WITH THE ADDED FORCING
AND UPPER DIVERGENCE FROM A JET MAX. SHEAR IS A LITTLE BETTER
SUNDAY...BUT INSTABILITY DROPS OFF BY AFTERNOON AS THE FRONT MOVES
THRU. LOWS REMAIN MILD SAT NITE WITH HIGHS TAKING A SIGNIFICANT
TUMBLE...AROUND 10 DEGREES...SUNDAY WITH PRECIP AND FROPA.

GFS HAS COME INTO BETTER AGREEMENT WITH THE ECMWF TAKING ON A MORE
PROGRESSIVE PATTERN MONDAY WITH THE FRONT AND ANY DEVELOPING UPPER
CLOSED LOW. THIS MEANS DECREASING POP SUNDAY NIGHT...AND ONLY A
SLIGHT CHC ALONG THE SRN TIER OF THE CWFA FOR MONDAY. LOWS SUN NITE
AROUND 10 DEGREES COOLER THAN SAT NITE WITH HIGHS MONDAY FROM 5 TO
10 DEGREES COOLER THAN SUN.

&&

.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
AS OF 200 PM THURSDAY...VERY LITTLE CONFIDENCE REMAINS IN THE EXT
PERIOD. THE 12Z GFS HAS COME INTO LINE A BIT WITH THE 00Z
ECMWF...HOWEVER THE LARGE SCALE PATTERN AND SENSIBLE WX EXPECTED
WITH EACH SCENARIO ARE AT MAJOR ODDS WITH EACH OTHER. AN ATTEMPT WAS
MADE TO FIND A CONSENSUS MODEL...HOWEVER THE GGEM AND NOGAPS BOTH
HAVE UNIQUE SOLNS OF THEIR OWN. THE FORMER INDICATING A TROPICAL
SYSTEM MOVING UP THE EAST COAST...AND THE LATTER PROGRESSING A
FRONTAL BAND OUT TO SEA WITH NO CLOSED OFF UPPER LOW. THIS LEAVES
LITTLE GUIDANCE TO RELY ON...SO THE LARGE SCALE UPPER PATTERN WILL
ENTAIL A COMPROMISE BTW THE 00Z EC AND THE 12Z GFS. THUS...A CLOSED
UPPER LOW OF MODERATE STRENGTH WILL BE EXPECTED TO DEVELOP OFF THE
ATL COAST LATE IN THE DAY TUE...AND SLOWLY RETROGRADE WEST SOUTH OF
RISING HEIGHTS AND A DEVELOPING HIGH ACROSS THE OH VALLEY AND GL
REGION.

AT THE LOW LEVELS...DRY AIR WILL BE SLOW TO OVERCOME TUE AS DEEP
SUBSIDENCE SHOULD BE THE STRONGEST IN A FAIRLY TIGHT Z/GRAD ALOFT
AND A WEDGE HIGH BUILDING IN AT THE SFC PRODUCING RATHER STAUNCH AND
GUSTY NE WINDS. WONT EXPECT MUCH CLOUD COVER IN THIS SITUATION...SO
EVEN THO SFC THETA/E WILL BE LOWERING DURING THE...MAX TEMPS SHOULD
STILL BE ABLE TO REACH NEAR NORMAL LEVELS. THE FORECAST GETS MUCH
TRICKIER AND LESS CONFIDENT WED THROUGH THU....YET THE MAIN IDEA
WILL BE TO ADVECT HIGHER AMOUNTS OF ATL MOISTURE TO THE AREA AS THE
SFC WAVE EITHER PERSISTS ALONG THE COASTAL BOUNDARY OR MOVES WEST
ACROSS S/RN GA. THEREFORE...POPS WILL BE INCREASED TO LOW END
CHANCES THROUGH THU...PRIMARILY ACROSS THE UPSLOPE REGIONS. MAX
TEMPS WILL REMAIN ADVERTISED NEAR NORMAL OR EVEN A FEW DEGREES BELOW
AS WIDESPREAD CLOUDINESS IS EXPECTED TO DEVELOP IN E/LY OR NE/LY
FLOW.

&&

.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
SCATTERED TO NUMEROUS TSTMS WILL LINGER ACROSS THE MOUNTAINS BEFORE
BECOMING ISOLATED LATER THIS EVENING. WILL HAVE TO MONITOR THE
PROGRESS THROUGH ABOUT 02 UTC...AS STORMS NEAR KAVL.
OTHERWISE...JUST VARIABLE...BUT MOSTLY SCT VFR LVL CLOUDS WILL BE
SEEN ACRS THE FA. STILL EXPECTING REDEVELOPMENT OF NOCTURNAL
STRATOCU...BUT CIG RESTRICTIONS ARE EXPECTED TO BE LIMITED. AREAS OF
5-6SM IN PRE-DAWN BR IS EXPECTED AS WELL...WITH LOCALLY IFR VSBYS
POSSIBLE IN THE MTN VALLEYS. GREATER CVRG OF AFTERNOON TSTMS ARE
EXPECTED ON FRIDAY AND HAVE INTRODUCED CB AT ALL TERMINAL LOCATIONS.

AT KCLT...SCT VFR LVL STRATOCU WILL LINGER INTO THE OVERNIGHT
HOURS...WITH LIGHT SE WINDS. WILL STICK CLOSE TO THE LATEST MAV/LAV
GUIDANCE FOR FLIGHT RESTRICTIONS...HANGING TOUGH WITH LOW VFR...BUT
KEEPING A HEDGE SCT LAYER FOR MVFR AND EVEN A FEW IFR STRATUS DURING
THE PRE-DAWN HOURS. ALSO PLAN ON JUST VFR LVL BR. WINDS TO REMAIN ON
LIGHT SIDE AND WITH A SOUTHERLY COMPONENT. INCREASED AFTERNOON TSTM
CHANCES WARRANTS AND INTRODUCTION OF CB MENTION.

OUTLOOK...PRECIP CHANCES INCREASE THROUGH SATURDAY...ESPECIALLY OVER
THE MTNS. MORNING FOG AND STRATUS ARE POSSIBLE...ESPECIALLY WHERE
RAIN FALLS. A COLD FRONT WILL CROSS THE AREA ON SUNDAY...POSSIBLY
BRINGING WIDESPREAD FLIGHT RESTRICTIONS TO THE AREA. VFR IS EXPECTED
MONDAY...THOUGH MOISTURE MAY NOT BE TOO FAR OFF TO OUR SOUTHEAST
ALONG THE STALLING FRONT.

&&

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

&&

SYNOPSIS...SBK
NEAR TERM...JDL
SHORT TERM...RWH
LONG TERM...SBK
AVIATION...CSH/JDL

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
342 PM EDT THU MAY 14 2009

GAZ010-017-018-026-NCZ033-035>037-048>053-056>059-062>065-068>070-
501>510-SCZ001>008-010-151945-
RABUN-HABERSHAM-STEPHENS-FRANKLIN-AVERY-ALEXANDER-IREDELL-DAVIE-
MADISON-YANCEY-MITCHELL-SWAIN-HAYWOOD-BUNCOMBE-CATAWBA-ROWAN-GRAHAM-
NORTHERN JACKSON-MACON-SOUTHERN JACKSON-TRANSYLVANIA-HENDERSON-
CLEVELAND-LINCOLN-GASTON-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-ANDERSON-
342 PM EDT THU MAY 14 2009

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 ARE IN THE FORECAST FOR THIS EVENING. THE
MAIN THREAT FROM THESE STORMS WILL BE LIGHTNING.

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

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

NONE.

GAZ028-029-NCZ071-072-082-SCZ009-011>014-019-151945-
HART-ELBERT-MECKLENBURG-CABARRUS-UNION NC-YORK-ABBEVILLE-LAURENS-
UNION SC-CHESTER-GREENWOOD-
342 PM EDT THU MAY 14 2009

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

.DAY ONE...THIS AFTERNOON AND TONIGHT.

ISOLATED THUNDERSTORMS ARE IN THE FORECAST FOR THIS EVENING. THE
MAIN THREAT FROM THESE STORMS WILL BE LIGHTNING.

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

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

NONE.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
618 PM EDT THU MAY 14 2009

NCZ049-050-142245-
MITCHELL-YANCEY-
618 PM EDT THU MAY 14 2009

...STRONG THUNDERSTORMS WILL AFFECT NORTHERN YANCEY AND MITCHELL
COUNTIES THROUGH 645 PM EDT...

AT 616 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SERIES OF STRONG THUNDERSTORMS STRETCHING FROM 5 MILES SOUTHWEST OF
BANNER HILL TO JUST NORTH OF ROCKY FORK...MOVING EAST AT 15 MPH.

THESE THUNDERSTORMS WILL MOVE ACROSS NORTHERN PARTS OF YANCEY AND
MITCHELL COUNTIES THROUGH 645 PM EDT. SMALL HAIL...WIND GUSTS OF 30
TO 40 MPH...AND TORRENTIAL RAINFALL ARE EXPECTED WITH THESE
STORMS.

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
648 PM EDT THU MAY 14 2009

NCZ033-048>050-142330-
AVERY-MADISON-MITCHELL-YANCEY-
648 PM EDT THU MAY 14 2009

...STRONG THUNDERSTORMS WILL AFFECT AVERY...MADISON...MITCHELL AND
YANCEY COUNTIES THROUGH 730 PM EDT...

AT 645 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM BULADEAN TO HOT
SPRINGS. THESE THUNDERSTORMS WERE MOVING EAST AT 15 MPH.

THE THUNDERSTORMS WILL AFFECT LOCATIONS FROM MARSHALL TO BURNSVILLE
TO NEWLAND THROUGH 730 PM THIS EVENING. ANY OF THE THUNDERSTORMS
ALONG THIS LINE COULD PRODUCE PEA SIZE HAIL...WIND GUSTS TO 35
MPH...TORRENTIAL DOWNPOURS...AND FREQUENT LIGHTNING. GO INSIDE AS
THIS LINE OF STORMS APPROACHES YOUR LOCATION.

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
733 PM EDT THU MAY 14 2009

NCZ033-048>050-052-053-150015-
AVERY-BUNCOMBE-HAYWOOD-MADISON-MITCHELL-YANCEY-
733 PM EDT THU MAY 14 2009

...STRONG THUNDERSTORMS AND HEAVY RAINFALL WILL AFFECT LOCATIONS
FROM ASHEVILLE TO NEWLAND THROUGH 815 PM EDT...

AT 728 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
HEAVY SHOWERS AND STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM
BAKERSVILLE TO NEAR CANTON...AND WEST TO THE TENNESSEE
BORDER...MOVING EAST AT 15 MPH.

THESE THUNDERSTORMS WILL HAVE THE POTENTIAL TO PRODUCE GUSTY WINDS
TO 35 MPH...SMALL HAIL...AND VERY HEAVY RAINFALL. RAINFALL RATES OF
1 TO 2 INCHES PER HOUR WILL BE POSSIBLE IN THE HEAVIEST SHOWERS.
THIS COULD PRODUCE LOCALIZED FLOODING...ESPECIALLY ACROSS PARTS OF
WESTERN MADISON COUNTY AND NORTHERN YANCEY COUNTY. A FLOOD ADVISORY
IS ALREADY IN EFFECT FOR NORTHERN HAYWOOD COUNTY.

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
803 PM EDT THU MAY 14 2009

NCZ049-150030-
YANCEY-
803 PM EDT THU MAY 14 2009

...A STRONG THUNDERSTORM WILL AFFECT YANCEY COUNTY THROUGH 830 PM
EDT...

AT 801 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 5 MILES WEST OF BURNSVILLE...MOVING EAST AT 15
MPH. THIS THUNDERSTORM WILL AFFECT MAINLY LOCATIONS IN AND NEAR
BURNSVILLE.

PEA SIZE HAIL AND WIND GUSTS OF 30 TO 40 MPH ARE EXPECTED WITH THIS
STORM. VERY HEAVY RAINFALL IS ALSO OCCURRING...WHICH COULD FLOOD LOW
LYING AREAS SUCH AS DITCHES AND UNDERPASSES. WATER LEVELS OF SMALL
STREAMS AND RIVERS WILL ALSO RISE.

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
847 PM EDT THU MAY 14 2009

NCZ049-150200-
YANCEY-
847 PM EDT THU MAY 14 2009

...HEAVY RAINFALL TO CONTINUE ACROSS YANCEY COUNTY THROUGH 945
PM...

A SERIES OF SHOWERS AND THUNDERSTORMS WILL CONTINUE TO PRODUCE
LOCALLY HEAVY RAINFALL ACROSS YANCEY COUNTY THROUGH 945 PM. RECENT
HEAVY DOWNPOURS HAVE PRODUCED RAINFALL AT RATES OF 2 TO 3 INCHES
PER HOUR IN THE BURNSVILLE AREA...AND ADDITIONAL RAINFALL AMOUNTS
OF ONE HALF TO ONE INCH WILL BE POSSIBLE.

HIGH WATER CONDITIONS ARE DEVELOPING ALONG BANKS CREEK AND THE
CANE RIVER WEST OF BURNSVILLE. WATER LEVELS COULD APPROACH OR
EXCEED BANKFULL IN LOW LYING AREAS THIS EVENING. BE VERY CAREFUL
IF DRIVING AFTER DARK. DO NOT ATTEMPT TO DRIVE THROUGH ANY FLOODED
ROADWAYS.

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
931 PM EDT THU MAY 14 2009

NCZ051-058-150230-
GRAHAM-SWAIN-
931 PM EDT THU MAY 14 2009

...STRONG THUNDERSTORMS WILL AFFECT GRAHAM AND SWAIN COUNTIES
THROUGH 1030 PM EDT...

AT 929 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM 3 MILES SOUTH OF
MARYVILLE TO 4 MILES WEST OF TAPOCO TO 17 MILES NORTHWEST OF
MURPHY...MOVING EAST AT 20 MPH.

THESE STORMS WILL AFFECT GRAHAM AND SWAIN COUNTIES THROUGH 1030
PM...INCLUDING TAPOCO...FONTANA VILLAGE...SANTEETLAH LAKE...FONTANA
LAKE AND STECOAH.

SMALL HAIL...WIND GUSTS OF 30 TO 40 MPH...AND VERY HEAVY RAINFALL
ARE POSSIBLE WITH THESE THUNDERSTORMS.

HG