Damaging Winds in North Carolina, April 4, 2008

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
257 PM EDT FRI APR 4 2008

.SYNOPSIS...
THE WEDGE OF HIGH PRESSURE THAT HAS BEEN OVER OUR AREA CONTINUES TO
WEAKEN AND RETREAT NORTHEASTWARD. A COLD FRONT IS EXPECTED TO CROSS
THE CAROLINAS LATE FRIDAY AND INTO EARLY SATURDAY MORNING. A WEAK AND
RELATIVELY DRY WEDGE OF HIGH PRESSURE WILL THEN MOVE OVER THE
EASTERN UNITED STATES ON SUNDAY AND REMAIN LARGELY IN PLACE THROUGH
THE MIDDLE OF NEXT WEEK. LATER IN THE WEEK...ANOTHER WEAK LOW IS
PROJECTED TO MOVE OVER THE REGION.

&&

.NEAR TERM /THROUGH SATURDAY/...
AN UPPER TROUGH WILL CROSS THE MS RIVER VALLEY TONIGHT...AND THE
SOUTHERN APPALACHIANS ON SATURDAY. COLD AIR DAMMING OVER THE AREA IS
ERODING...BUT SOME AREAS ALONG THE BLUE RIDGE MAY BE SLOW TO SEE
THE WARM SECTOR AIR ARRIVE. UPGLIDE CONTINUES TO DECREASE...BUT AS A
COLD FRONT APPROACHES FROM THE WEST...INSTABILITY AND OMEGA WILL
INCREASE...SUPPORTING INCREASING PRECIPITATION COVERAGE AND AMOUNTS.
WITH SUBSTANTIAL SHEAR PRESENT...A THREAT OF SEVERE WEATHER EXISTS
INTO TONIGHT...AND A TORNADO WATCH HAS BEEN ISSUED FOR NORTHEAST
GEORGIA AND WESTERN PORTIONS OF THE UPSTATE INTO LATE EVENING...
NEAR THE THERMAL MOISTURE BOUNDARY AT THE PERIPHERY OF THE WEDGE.
MINIMUM TEMPERATURES WILL BE RATHER WARM UNDER CLOUDS AND WITH THE
WIND UP IN A TIGHTENING GRADIENT.

A SURFACE WAVE IS EXPECTED TO MOVE ALONG THE FRONT SATURDAY...
REACHING OUR AREA FROM THE SOUTHWEST AROUND DAWN...WHILE THE FRONT
SLOWS. THIS WILL SET THE NORTHERN AND CENTRAL PORTIONS OF THE AREA
UP FOR A PROLONGED PERIOD OF STRATIFORM RAIN NORTH OF THE SURFACE
WAVE...WHILE THE SOUTHEASTERN PORTION OF THE AREA REMAINS IN THE
UNSTABLE WARM SECTOR. HIGH POPS WILL BE CARRIED THROUGH THE
DAY...WITH TEMPERATURE GAIN LIMITED...ESPECIALLY OUTSIDE THE WARM
SECTOR.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
AS OF 300 PM FRIDAY...TIMING APPEARS TO BE THE MAJOR DIFFERENCE IN
THE MDLS EARLY IN THE SHORT RANGE. GFS IS THE FASTEST WITH THE
DEPARTING SHORT WAVES SAT NITE. THE NAM...SREF AND ECMWF ALL ARE
DEEPER AND SLOWER WITH THE WAVES. THIS RESULTS IN A SLOWER SURFACE
LOW TRACKING UP THE EAST COAST SAT NITE. WILL TREND TOWARD THE
SLOWER MODELS AND KEEP HIGH POP EARLY FRI EVENING...THEN DIMINISH TO
NO POP AFTER MIDNIGHT. DAMMING HIGH PRESSURE SETS UP ACROSS THE AREA
SUNDAY AND HOLDS ON THRU MONDAY. LOOKS LIKE CLOUDS WILL CLEAR SUNDAY
BEFORE FLOW ABOVE THE HIGH PRESSURE DOME TURNS SLY AND LOW LEVEL
MOISTURE RETURNS SUNDAY NIGHT INTO MONDAY. SUNDAY SHOULD BE DRY WITH
PATCHY LIGHT RAIN RETURNING SUNDAY NIGHT AND MONDAY. LOWS SHOULD BE
ABOVE NORMAL SAT AND SUN NITES. HIGHS NEAR NORMAL SUNDAY THEN A
LITTLE COOLER MONDAY WITH INCREASING CLOUDS.

&&

.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
AS OF 230 PM FRIDAY...NOT MUCH CHANGE FROM THE PREVIOUS DAYS MEDIUM
RANGE FORECAST. THE MAIN SYNOPTIC FEATURE CONTINUES TO BE THE
PERSISTENT WEDGE OF WEAK HIGH PRESSURE OVER THE CAROLINAS THAT
STICKS AROUND THROUGH THURSDAY OF NEXT WEEK. THE WEDGE SHOULD
EVENTUALLY BREAK DOWN AS A WEAK COLD FRONT ASSOCIATED WITH A LOW
WELL TO OUR NORTH PUSHES THE WEDGE FURTHER OFFSHORE. DECIDED NOT TO
ALTER POPS VERY MUCH FOR TUES...WED...OR THURS...BUT I DID INCREASE
THEM TO SOLID CHANCE FOR FRI AND EARLY SAT. HPCS POPS CONTINUE TO BE
A BIT MORE OPTIMISTIC FOR MOST OF THE PERIOD...HOWEVER I AM STILL
NOT CONVINCED THERE WILL BE ENOUGH LOW LEVEL DYNAMIC FORCING TO
PRODUCE PRECIP. AS FAR AS TEMPS GO...VALUES SHOULD REMAIN CLOSE TO
CLIMATOLOGY IF NOT A FEW DEGREES ABOVE AS LONG AS THE PREDOMINATE
WINDS STAY FROM THE SOUTHEAST.

&&

.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
A COMPLEX FORECAST WITH THIS PACKAGE. THE COLD AIR DAMMING NOW IN
PLACE IS EXPECTED TO ERODE WITH HEATING AND INCREASING LOW LEVEL
WINDS THIS AFTERNOON...RESULTING IN IFR CONDITIONS....AND SCATTERED
CONVECTION. BY LATE EVENING CEILINGS ARE EXPECTED TO LOWER AGAIN TO
MVFR AS THE COLD FRONT APPROACHES FROM THE WEST. AFTER MIDNIGHT
SHOWERS AND THUNDERSTORMS ASSOCIATED WITH THE FRONT WILL LOWER
VISIBILITY TO MVFR WHILE CEILINGS LOWER TO IFR. SHORTLY AFTER DAWN A
SLOW MOVING SURFACE WAVE MOVING ALONG THE STALLING FRONT WILL SPREAD
STRATIFORM PRECIPITATION ACROSS ALL THE TAF SITES BUT KAND...WHICH
REMAINS IN THE WARM SECTOR WITH A SOUTHERLY WIND. WINDS AT OTHER
SITES WILL RANGE FROM NORTHERLY TO NORTHEASTERLY. MODEL GUIDANCE IS
IN FAIR AGREEMENT ON HOLDING CEILINGS AND VISIBILITY DOWN AS THE
WAVE SLOWLY CROSSES THE AREA SATURDAY MORNING...DESPITE A WEAK
DOWNSLOPE COMPONENT AT SOME FOOTHILL TAF SITES...AS UPGLIDE SETS UP
OVER THE NEWLY ARRIVING SURFACE RIDGE NORTH OF THE WAVE.

OUTLOOK...SHOWER AND TSTM CHANCES WILL REMAIN QUITE HIGH THROUGH AT
LEAST SATURDAY AFTERNOON. CONDITIONS MAY IMPROVE BRIEFLY SAT
NIGHT/SUNDAY...BUT ANOTHER COLD AIR DAMMING EPISODE APPEARS LIKELY
FOR MUCH OF NEXT WEEK.

&&

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

&&

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

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
346 PM EDT FRI APR 4 2008

GAZ010-017-018-026-028-029-SCZ001-002-004-005-010-011-052000-
RABUN-HABERSHAM-STEPHENS-FRANKLIN-HART-ELBERT-OCONEE MOUNTAINS-
PICKENS MOUNTAINS-GREATER OCONEE-GREATER PICKENS-ANDERSON-ABBEVILLE-
346 PM EDT FRI APR 4 2008

...TORNADO WATCH 165 IN EFFECT UNTIL 10 PM EDT THIS EVENING...

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

.DAY ONE...THIS AFTERNOON AND TONIGHT

PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE
INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS.

   TORNADO WATCH.

A COLD FRONT WILL CONTINUE TO PUSH EASTWARD INTO THE NORTHEAST
GEORGIA AND THE WESTERN UPSTATE TONIGHT. SOME OF THE THUNDERSTORMS
ASSOCIATED WITH THIS FRONT WILL BECOME SEVERE WITH DAMAGING WIND
GUSTS...AND POSSIBLY POSSIBLY A BRIEF ISOLATED TORNADO OR TWO.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

THE THREAT FOR SEVERE WEATHER COULD LINGER INTO SATURDAY MORNING
AS A LINE OF THUNDERSTORMS ALONG A COLD FRONT CONTINUES TO PUSH
EASTWARD. THE MAIN THREAT AREA FOR SATURDAY MORNING WOULD BE
SOUTH AND EAST OF THE I-85 CORRIDOR WHERE THESE THUNDERSTORMS
COULD PRODUCE STRONG DAMAGING WIND GUSTS...AND A BRIEF ISOLATED
TORNADO OR TWO.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

NCZ033-035>037-048>053-056>059-062>065-068>072-082-501>510-SCZ003-
006>009-012>014-019-052000-
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-
GREENVILLE MOUNTAINS-GREATER GREENVILLE-SPARTANBURG-CHEROKEE-YORK-
LAURENS-UNION SC-CHESTER-GREENWOOD-
346 PM EDT FRI APR 4 2008

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

.DAY ONE...THIS AFTERNOON AND TONIGHT

A COLD FRONT WILL THEN PUSH EASTWARD INTO THE WESTERN CAROLINAS
TONIGHT. AHEAD OF THIS FRONT...NUMEROUS SHOWERS AND SCATTERED
THUNDERSTORMS WILL DEVELOP THIS EVENING. LATER TONIGHT ALONG THIS
FRONT...A LINE OF THUNDERSTORMS IS EXPECTED TO DEVELOP. WITH A
STRONGLY FORCED ATMOSPHERE IN PLACE...STRONG SHEAR AND WEAK
INSTABILITY WILL COMBINE TO CREATE THE THREAT FOR SEVERE WEATHER.
SOME OF THE THUNDERSTORMS THIS EVENING OR LATER TONIGHT COULD
BECOME SEVERE PRODUCING STRONG...DAMAGING WIND GUSTS AND POSSIBLY
A BRIEF ISOLATED TORNADO OR TWO.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

THE THREAT FOR SEVERE WEATHER COULD LINGER INTO SATURDAY MORNING
AS A LINE OF THUNDERSTORMS ALONG A COLD FRONT CONTINUES TO PUSH
EASTWARD. THE MAIN THREAT AREA FOR SATURDAY MORNING WOULD BE
SOUTH AND EAST OF THE I-85 CORRIDOR WHERE THESE THUNDERSTORMS
COULD PRODUCE STRONG DAMAGING WIND GUSTS...AND A BRIEF ISOLATED
TORNADO OR TWO.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
425 PM EDT FRI APR 4 2008

GAZ010-017-042200-
HABERSHAM-RABUN-
425 PM EDT FRI APR 4 2008

...STRONG THUNDERSTORMS WILL AFFECT HABERSHAM AND RABUN COUNTIES
AFTER 545 PM EDT...

AT 425 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM ELLIJAY TO
FAIRMOUNT IN NORTHERN GEORGIA...OR ROUGHLY 30 MILES WEST OF
DAHLONEGA...MOVING NORTHEAST AT 35 MPH.

THESE THUNDERSTORMS HAVE A HISTORY OF PRODUCING LARGE HAIL. THE
STORMS WILL BE CLOSELY MONITORED AS THEY PROGRESS EASTWARD TOWARD
RABUN AND HABERSHAM COUNTIES OVER THE NEXT HOUR...AND A WARNING
COULD BE NEEDED IF THEY HOLD TOGETHER.

AT A MINIMUM...BE PREPARED FOR TORRENTIAL RAINFALL...FREQUENT
LIGHTING...WIND GUSTS TO 40 MPH...AND SMALL HAIL FROM CLAYTON TO
CLARKESVILLE AFTER 545 PM EDT THIS EVENING.

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
515 PM EDT FRI APR 4 2008

GAZ010-017-018-SCZ001-004-042215-
GREATER OCONEE-HABERSHAM-OCONEE MOUNTAINS-RABUN-STEPHENS-
515 PM EDT FRI APR 4 2008

...STRONG THUNDERSTORMS WILL AFFECT HABERSHAM...RABUN...STEPHENS AND
WESTERN OCONEE COUNTIES THROUGH 615 PM EDT...

AT 515 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM MURPHY TO 11 MILES
SOUTHWEST OF DAHLONEGA...MOVING EAST AT 35 MPH.

THESE STORMS WILL BE NEAR...
  BATESVILLE BY 550 PM EDT.
  DEMOREST BY 555 PM EDT.
  NACOOHE LAKE BY 600 PM EDT.
  LAKE RABUN BY 610 PM EDT.
  TALLULAH FALLS BY 615 PM EDT.

PEA SIZE HAIL...WIND GUSTS UP TO 40 MPH...AND TORRENTIAL RAINFALL
ARE EXPECTED WITH THESE STORMS.

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
522 PM EDT FRI APR 4 2008

NCZ051-058-059-062-063-042215-
GRAHAM-MACON-NORTHERN JACKSON-SOUTHERN JACKSON-SWAIN-
522 PM EDT FRI APR 4 2008

...STRONG THUNDERSTORMS WILL AFFECT JACKSON...MACON...SOUTHEASTERN
GRAHAM AND SOUTHERN SWAIN COUNTIES THROUGH 615 PM EDT...

AT 522 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM ROBBINSVILLE TO 3
MILES NORTHWEST OF YOUNG HARRIS...MOVING EAST AT 40 MPH.

THESE STORMS WILL BE NEAR...
  STECOAH BY 530 PM EDT.
  NANTAHALA LAKE BY 535 PM EDT.
  ALARKA BY 550 PM EDT.
  OTTO BY 600 PM EDT.
  SYLVA BY 610 PM EDT.
  CULLOWHEE BY 615 PM EDT.

WIND GUSTS OF 30 TO 40 MPH ARE EXPECTED WITH THESE STORMS...AND PEA
SIZE HAIL IS POSSIBLE.

HG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
539 PM EDT FRI APR 4 2008

GAZ018-026-028-042245-
FRANKLIN-HART-STEPHENS-
539 PM EDT FRI APR 4 2008

...A STRONG THUNDERSTORM WILL AFFECT FRANKLIN...NORTHERN HART AND
SOUTHEASTERN STEPHENS COUNTIES THROUGH 645 PM EDT...

AT 539 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 4 MILES WEST OF JEFFERSON...MOVING NORTHEAST AT
35 MPH.

THIS STORM WILL BE NEAR...
  CARNESVILLE BY 620 PM EDT.
  MARTIN BY 630 PM EDT.
  LAVONIA BY 635 PM EDT.
  WHITWORTH BY 640 PM EDT.

PEA SIZE HAIL...AND WIND GUSTS OF 30 TO 40 MPH ARE EXPECTED WITH THIS
STORM. FREQUENT LIGHTNING IS ALSO POSSIBLE WITH THIS STORM. IF
OUTDOORS...STAY AWAY FROM ISOLATED HIGH OBJECTS SUCH AS TREES. MOVE
INDOORS IF POSSIBLE. WHEN INDOORS...STAY AWAY FROM WINDOWS AND DOORS
AND AVOID USING TELEPHONES UNLESS IT IS AN EMERGENCY. TRY TO UNPLUG
UNNECESSARY ELECTRICAL APPLIANCES BEFORE THE THUNDERSTORM APPROACHES.

HG