Flash Flood in North Carolina, September 5, 2006

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
312 AM EDT TUE SEP 5 2006

.SHORT TERM /TODAY THROUGH THURSDAY NIGHT/...
SHOWERS AND THUNDERSTORMS WITH VERY HEAVY RAIN WERE ONGOING ALONG
THE EASTERN ESCARPMENT AT 3 AM. FLOW IS EXPECTED TO CONTINUE TO
VEER OUT OF THE WEST IN THE LOW LEVELS THIS MORNING...WHICH SHOULD
LIMIT FLASH FLOOD THREAT ALONG THE LEE SLOPES. THAT IS IF THE GFS
IS RIGHT. THE NAM/WRF MAINTAINS MORE OF A BACKED FLOW...BUT SO FAR
IT/S TRACK RECORD WITH THIS SYSTEM HAS NOT BEEN AS GOOD AS THE
GFS/S. ALSO...VEERING HAS BEEN EVIDENT ON THE KGSP-WSR88D OVER THE
PAST COUPLE HOURS. THIS IS ALSO THE RADAR TREND AS WELL AS CELLS
ARE NOT HUGGING THE LEE SLOPES OF THE NC FOOTHILLS THE WAY THEY
DID LAST NIGHT. HOPEFULLY THIS WILL KEEP THE HEAVIER RAIN CLEAR OF
THE ROCKY BROAD RIVER/LAKE LURE AREA WHICH HAD 2 TO 4 INCHES OF
RAIN ABOUT 24 HOURS AGO.

WHILE BOTH THE GFS AND WRF BRING THE RT ENTRANCE REGION OF A STRONG
250 MB JET ACROSS THE REGION TODAY...THE MODELS HAVE SOME
SIGNIFICANT DIFFERENCES AT THE SURFACE WHICH WILL AFFECT GREATLY THE
DISTRIBUTION AND INTENSITY OF RAINFALL. THE NAM MAINTAINS AN E-W
ORIENTED SURFACE BNDRY ACROSS THE NC FOOTHILLS AND PIEDMONT. THE GFS
ON THE OTHER HAND CONTINUES TO DEVELOP A MORE N-S ORIENTED BNDRY
FARTHER EAST OVER CENTRAL NC AND LOSES THE WEAK CAD. IF THE NAM IS
RIGHT...THE POTENTIAL EXISTS FOR A FAIRLY LARGE AREA OF HEAVY RAIN
OVER THE NC FOOTHILLS AND PIEDMONT THIS AFTERNOON AND EVENING. THE
GFS WOULD IMPLY THE THREAT IS HIGHER FARTHER EAST. AS HPC
MENTIONED...THERE IS AN AXIS OF GREATER THAN 2 INCH PW/S OVER THE
EASTERN CAROLINAS...WHICH WOULD IMPLY A GREATER THREAT TO OUR EAST.
IN FACT...THEIR DAY 1 QPF GENERALLY HAS A HALF INCH OR LESS OF QPF
OVER OUR FORECAST AREA...AND FAVORS THE N-S ORIENTATION OF THE GFS/S
SURFACE PRESSURE FIELD.

THE FORECAST OFFICES IN RNK AND RAH HAVE BOTH ISSUED FLASH FLOOD
WATCHES ALONG OUR COMMON BORDERS...AND I CERTAINLY DON/T BLAME THEM.
I AM GOING TO WAIT UNTIL THE 0600 UTC WRF COMES IN...TO SEE IF IT
CONTINUES TO MAINTAIN THE IN SITU CAD BNDRY. IF IT DOES...THEN I
WILL PROBABLY ALSO ISSUE A WATCH FOR SOME OR ALL OF MY NC FOOTHILLS
OR PIEDMONT ZONES SOMETIME BETWEEN 4 AND 6 AM LOCAL TIME WHICH
WILL LIKELY RUN THROUGH MIDNIGHT.

WED AND THU LOOK TO BE FAIR WEATHER DAYS...WITH HIGHS GENERALLY
IN THE 70S MTNS...AND LOW 80S ELSEWHERE...WITH MUCH LOWER
DEWPOINTS.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
A LONGWAVE TROUGH WILL SLOWLY DEAMPLIFY OVER A LARGE PORTION OF
THE EASTERN STATES FOR THE REMAINDER OF THE WEEK...AS A SHORTWAVE
TROUGH BEGINS TO AMPLIFY AND MOVE OVER THE UPPER GREAT LAKES EARLY
SATURDAY. SLIGHT CHANCES OF DIURNAL CONVECTION WILL BE THE NORM
EVERY AFTERNOON THROUGH MONDAY...WHEN THE WEAK FRONT IS EXPECTED
TO LAY OUT OVER THE MOUNTAINS AND POSSIBLY WASH OUT SHORTLY
THEREAFTER. THIS FEATURE IS THE MOST UNCERTAIN PART OF THE
EXTENDED PERIOD...THOUGH MODELS ARE IN GOOD AGREEMENT THAT THERE
WILL BE LITTLE IN THE AMOUNT OF RAIN FOR THE CWA FROM MID WEEK TO
THE END OF THE WEEK. WEAK HIGH PRESSURE WILL BUILD OVER THE MID
MISSISSIPPI VALLEY...EXTENDING INTO THE MID ATLANTIC
STATES...ALLOWING FOR MAX TEMPS TO GET BACK INTO THE MID 80 DEGREE
RANGE FOR THE PIEDMONT AREAS...WITH FAIRLY LOW DEWPOINTS DURING
THIS DRIER PERIOD.

&&

.AVIATION...
CLOSER TO BETTER LARGE SCALE LIFT...KAVL WILL RATE THE GREATEST
SHOWER CHANCES AND VSBY REDUCTIONS DUE TO PCPN THROUGH THE NEAR
TERM...WITH THE MAIN THREAT OF SIG WX AT KGSP/KAND/KCLT SHAPING UP
TO BE A PERIOD OF IFR CONDS...MAINLY FROM CIGS...WITHIN THE MOIST
WAA PATTERN. SHOWER MENTION WILL BE CARRIED AT KGSP/KCLT/KAND WITHIN
PRE-DAWN TEMPO GROUPS OF IFR AND/OR LOW MVFR. DEPENDING ON PCPN CVRG
AS THE DAYTIME MORNING PERIOD WEARS ON...PROBABLY WILL TAKE UNTIL
MIDDAY TO LOSE MOST OF THE CIG/VBSY RESTRICTION. WILL CONTINUE WITH
VCSH/CB COMBO AT ALL TERMINALS THIS AFTERNOON WITH INSTABILITY AXIS
OUT AHEAD OF COLD FRONT. OVERALL PCPN CHANCES THIS AFTERNOON PRETTY
HIGH...PROBABLY WILL WARRANT AT LEAST A TEMPO GROUP FOR SHOWERS...
BUT DUE TO TIMING UNCERTAINTY WILL LEAVE AS VICINITY.

&&

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

SHORT TERM...MCAVOY
LONG TERM...GMS
AVIATION...CSH

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
601 AM EDT MON SEP 4 2006

GAZ010-017-018-026-028-029-NCZ033-035>037-048>053-056>059-062>065-
068>072-082-501>510-SCZ001>014-019-051015-
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-
601 AM EDT MON SEP 4 2006

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

.DAY ONE...TODAY AND TONIGHT

NUMEROUS TO WIDESPREAD SHOWERS AND THUNDERSTORMS WILL AFFECT THE
REGION TODAY AND TONIGHT. ACTIVITY WILL BE THE MOST WIDESPREAD
OVER THE MOUNTAINS AND FOOTHILLS OF THE WESTERN CAROLINAS. A
COUPLE INCHES OF RAIN IS POSSIBLE IN PARTS OF THIS AREA. IF THE
RAIN FALLS WHERE THE GROUND IS ALREADY SATURATED...ISOLATED FLASH
FLOODING MAY DEVELOP.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY
NUMEROUS SHOWERS AND THUNDERSTORMS WILL CONTINUE INTO TUESDAY
EVENING ACROSS THE WESTERN CAROLINAS AND NORTHEAST GEORGIA. THE
HEAVY RAIN THREAT IS EXPECTED TO SHIFT EAST INTO THE PIEDMONT ON
TUESDAY. AGAIN...A FEW LOCATIONS COULD SEE LOCALLY EXCESSIVE
RAINFALL.

.SPOTTER INFORMATION STATEMENT...
SPOTTERS ACTIVATION MAY BE NEEDED LATER TODAY FOR THE PURPOSE OF
REPORTING RAINFALL AMOUNTS AND STREAM LEVELS.

MCAVOY

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1108 PM EDT MON SEP 4 2006

NCZ072-050430-
CABARRUS-
1108 PM EDT MON SEP 4 2006

...THUNDERSTORMS WILL PRODUCE HEAVY RAIN OVER CABARRUS COUNTY
THROUGH 1230 AM...

AT 1057 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
THUNDERSTORMS PRODUCING VERY HEAVY RAINFALL IN LOCATIONS FROM
KANNAPOLIS SOUTH TO THE SPEEDWAY AREA. AS THIS ACTIVITY MOVES
NORTHEAST ACROSS THE COUNTY...HOURLY RAINFALL RATES OF OVER AN INCH
WILL BE LIKELY ACROSS THE NORTHERN PART OF THE COUNTY...INCLUDING
THE CITIES OF CONCORD AND KANNAPOLIS.

HEAVY RAINS MAY FLOOD LOW LYING AREAS SUCH AS DITCHES AND
UNDERPASSES. AVOID THESE AREAS AND DO NOT CROSS FLOODED ROADS. WATER
LEVELS OF SMALL STREAMS AND RIVERS MAY ALSO RISE...THEREFORE SEEK
HIGHER GROUND IF THREATENED BY FLOOD WATERS.

LANE

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1140 PM EDT MON SEP 04 2006

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

1045 PM     FLOOD            8 N CHARLOTTE           35.31N 80.83W
09/04/2006                   MECKLENBURG        NC   FIRE DEPT/RESCUE

            FLOODING REPORTED BY CHARLOTTE FIRE DISPATCH AT LAKEVIEW
            ROAD AND TRINITY ROAD. ALSO AT HARRIS BLVD AND MT. HOLLY
            HUNTERSVILLE ROAD WITH CARS STUCK IN 3 FT OF WATER.

&&

BSH

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
1218 AM EDT TUE SEP 5 2006

NCZ064-065-509-050530-
HENDERSON-POLK MOUNTAINS-TRANSYLVANIA-
1218 AM EDT TUE SEP 5 2006

...SHOWERS AND THUNDERSTORMS WITH HEAVY RAINFALL INCREASING ACROSS
THE SOUTHERN MOUNTAINS...

AT 1215 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
THUNDERSTORMS PRODUCING RAINFALL RATES OF 1 TO 2 INCHES PER HOUR
EXTENDING FROM NEAR ETOWAH...TO BREVARD...TO THE ROSMAN AREA.

THESE SHOWERS AND STORMS WILL CONTINUE TO PRODUCE VERY HEAVY
RAINFALL ACROSS MUCH OF TRANSYLVANIA COUNTY...AS WELL AS WESTERN
HENDERSON COUNTY THROUGH 130 AM.

HEAVY RAINS MAY FLOOD LOW LYING AREAS SUCH AS DITCHES AND
UNDERPASSES. AVOID THESE AREAS AND DO NOT CROSS FLOODED ROADS. WATER
LEVELS OF SMALL STREAMS AND RIVERS MAY ALSO RISE...THEREFORE SEEK
HIGHER GROUND IF THREATENED BY FLOOD WATERS.

LANE

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
156 AM EDT TUE SEP 5 2006

NCZ065-050700-
HENDERSON-
156 AM EDT TUE SEP 5 2006

...STRONG THUNDERSTORMS PRODUCING HEAVY RAINFALL OVER HENDERSON
COUNTY...

AT 150 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS EXTENDING FROM FLAT ROCK...WEST TO THE
TRANSYLVANIA COUNTY LINE. THESE STORMS WERE PRODUCING HOURLY
RAINFALL RATES OF 1 TO 2 INCHES PER HOUR ACROSS THE SOUTHWEST PART
OF THE COUNTY.

AS THIS ACTIVITY CONTINUES TO SHIFT NORTHEAST...RAINFALL RATES CAN
BE EXPECTED TO INCREASE IN THE HENDERSONVILLE...DANA...AND FLAT ROCK
AREAS. AREAS ACROSS THE EASTERN PORTION OF THE COUNTY EXPERIENCED
HEAVY RAINFALL LAST NIGHT...AND THE ADDITIONAL RAINFALL MAY RESULT
IN RAPID RISES ON STREAMS LEADING OUT OF THE MOUNTAINS EARLY THIS
MORNING.

HEAVY RAINS MAY FLOOD LOW LYING AREAS SUCH AS DITCHES AND
UNDERPASSES. AVOID THESE AREAS AND DO NOT CROSS FLOODED ROADS. WATER
LEVELS OF SMALL STREAMS AND RIVERS MAY ALSO RISE...THEREFORE SEEK
HIGHER GROUND IF THREATENED BY FLOOD WATERS.

LANE

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
234 AM EDT TUE SEP 5 2006

NCZ064-050730-
TRANSYLVANIA-
234 AM EDT TUE SEP 5 2006

...STRONG THUNDERSTORMS PRODUCING HEAVY RAINFALL LINGERING OVER
SOUTHEAST TRANSYLVANIA COUNTY...

AT 230 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
HEAVY THUNDERSTORMS SOUTH OF US 64. THESE STORMS WERE PRODUCING
HOURLY RAINFALL RATES OF 1 TO 2 INCHES PER HOUR ACROSS THE SOUTHEAST
PART OF THE COUNTY. RESIDENTS ARE ADVISED TO BE WARY OF ELEVATED
STREAM LEVELS IN THIS AREA AND WATCH OUT FOR STANDING WATER ON
ROADS...ESPECIALLY US 276.

HEAVY RAINS MAY FLOOD LOW LYING AREAS SUCH AS DITCHES AND
UNDERPASSES. AVOID THESE AREAS AND DO NOT CROSS FLOODED ROADS. WATER
LEVELS OF SMALL STREAMS AND RIVERS MAY ALSO RISE...THEREFORE SEEK
HIGHER GROUND IF THREATENED BY FLOOD WATERS.

CSH

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
239 AM EDT TUE SEP 5 2006

NCZ062-050745-
MACON-
239 AM EDT TUE SEP 5 2006

...HEAVY SHOWERS AND SOME THUNDERSTORMS POSSIBLE OVER MACON COUNTY
EARLY THIS MORNING...

AT 235 AM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
INCREASING SHOWERS AND A FEW THUNDERSTORMS ALL ACROSS THE COUNTY. THE
GENERAL WEATHER PATTERN IS FAVORABLE FOR ENHANCED PRECIPITATION
ACROSS THIS PART OF THE NORTH CAROLINA MOUNTAINS. LOCALIZED HOURLY
RAINFALL RATES OF 1 TO 2 INCHES PER HOUR COULD DEVELOP.  RESIDENTS
ARE ADVISED TO BE WARY OF ELEVATED STREAM LEVELS IN THIS AREA AND
WATCH OUT FOR STANDING WATER ON ROADS THROUGHOUT THE LATE NIGHT
HOURS.

HEAVY RAINS MAY FLOOD LOW LYING AREAS SUCH AS DITCHES AND
UNDERPASSES. AVOID THESE AREAS AND DO NOT CROSS FLOODED ROADS. WATER
LEVELS OF SMALL STREAMS AND RIVERS MAY ALSO RISE...THEREFORE SEEK
HIGHER GROUND IF THREATENED BY FLOOD WATERS.

CSH