Severe Thunderstorm Warning 9, NWS Wilmington, NC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
254 PM EDT SUN MAY 2 2004

.DISCUSSION...
TONS OF CONVECTION THIS AFTERNOON ACROSS THE INLAND COUNTIES
IS A PRECURSOR FOR WHAT IS TO COME TONIGHT. MODEL OMEGA FIELDS AND
UPSTREAM ACTIVITY DEVELOPING ACROSS GEORGIA INDICATE A SQUALL
LINE...OR AT LEAST A MASSED AREA OF DEEP CONVECTION MOVING FROM WEST
TO EAST ACROSS THE EASTERN CAROLINAS AHEAD OF A COLD FRONT. HAVE
GONE WITH CATEGORICAL POPS ACROSS THE ENTIRE AREA TONIGHT WITH THIS
FRONT. SUBTLE TIMING DIFFERENCES EXIST WITH THE FRONT - THE ETA IS
SLOWER THAN EITHER THE GFS OR THE NGM. DIFFERENCES ONLY ADD UP TO A
COUPLE HOURS EITHER WAY AT THE COAST...BUT THE ETA SEEMED A LITTLE
SLOW WITH THE FRONT EARLIER THIS MORNING ACROSS THE MOUNTAINS AND
NORTH GEORGIA. HAVE TRENDED TOWARD THE SLIGHTLY FASTER GFS/NGM.

WITH PRECIPITABLE WATER VALUES RUNNING NEARLY 1.7 INCHES...WELL
ABOVE CLIMATOLOGICAL NORMS...TRAINING THUNDERSTORMS WILL BE ABLE TO
DROP EXCESSIVE RAINS VERY QUICKLY. STORM TOTAL PRECIP OFF THE RADAR
SHOWS A SWATH ACROSS THE CAPE FEAR COUNTIES OF 2-4 INCHES BEGINNING
YESTERDAY MORNING. PLENTY OF WATER IS STANDING IN THE YARD OF THE
NWS OFFICE CURRENTLY TOO. HAVE INCLUDED MENTION OF HEAVY RAINFALL IN
THE ZONES AGAIN TONIGHT.

THE FRONT SHOULD DECELERATE AS IT CROSSES THE COASTLINE MONDAY
MORNING...WITH CLOUD COVER AND LINGERING SHOWERS TAKING A GOOD
PORTION OF THE DAY TO CLEAR AT THE COAST. INLAND AREAS COULD SEE
SOME SUNSHINE ESPECIALLY IN THE AFTERNOON. TEMPERATURES WILL NOT
BUDGE MUCH WITH COLD ADVECTION BEHIND THE FRONT. TEMPERATURES MONDAY
NIGHT AND AGAIN TUESDAY NIGHT WILL REACH THE UPPER 40S TO NEAR 50
AWAY FROM THE IMMEDIATE COAST.

THE REMAINDER OF THE PERIOD LOOKS DRY WITH A MAINLY OFFSHORE FLOW
EXPECTED. A LARGE RIDGE ALOFT ACROSS THE EASTERN U.S. AND RAPIDLY
WARMING 850 MB TEMPS THE SECOND HALF OF THE WEEK WILL TRANSLATE TO
HIGHS POSSIBLY IN THE UPPER 80S INLAND BY FRIDAY AND SATURDAY. THE
POSSIBILITY EXISTS FOR A BACKDOOR FRONT TO SLIDE DOWN THE EAST COAST
NEXT SATURDAY OR SUNDAY...BUT POTENTIAL LOOKS TOO SMALL TO AFFECT
THE FORECAST HIGHS AT THIS POINT.

&&

.MARINE...
A MAJORITY OF THE ACTION OVER THE COASTAL WATERS WILL OCCUR WITHIN
THE NEXT 24 TO 36 HOURS. STRONG S TO SW FLOW AHEAD OF ADVANCING COLD
FRONT WILL NECESSITATE SCA TONIGHT...CONTINUING TOMORROW. FRONTAL
TIMING IS BIGGEST QUESTION MARK RIGHT NOW. GFS TIMES FROPA MON AFTN
WHILE ETA DELAYS FROPA BY ABOUT 6 HOURS.

COMPARING BOTH MODELS...THE GFS SOLUTION SEEMS TO BE THE BETTER OF
THE TWO. THE 12Z ETA 18Z PANEL WAS A FEW HOURS SLOWER THAN THE SFC
FRONT...WITH THE GFS SLIGHTLY FASTER. THE LARGE PROBLEM WITH THE
GFS CONTINUES TO BE WIND SPEEDS THAT ARE TOO STRONG. WILL USE ETA
WIND SPEEDS AHEAD OF THE FRONT...WHICH IS TYPICALLY WHERE ETA WINDS
BEAT THE GFS. AFTER FROPA GFS WINDS SEEM A LITTLE MORE REASONABLE.

OVERALL WW3 GUIDANCE IS DOING A GOOD JOB WITH CURRENT CONDITIONS.
18Z OUTPUT WAS 6.7 FT AT 41013 COMPARED TO THE 6.6 FT 18Z READING.
SEE NO REASON TO ARGUE WITH WW3 NUMBERS BUT DID KNOCK ABOUT A FOOT
OFF OF OUTPUT LATE TONIGHT AND MON DUE TO AGGRESSIVE GFS PRE-FRONTAL
WINDS.

OFFSHORE FLOW DEVELOPING MON CONTINUES INTO MON NIGHT. LITTLE TO NO
CAA BEHIND THE FRONT...DO NOT EXPECT WINDS TO GO OVER 20 KT. HIGH
BUILDING INTO THE REGION TUE MOVES OFF THE COAST TUE NIGHT THEN
SLOWLY DRIFTS S OF THE WATERS WED THRU FRI.

&&

.PRELIMINARY POINT TEMPS/POPS...
WILMINGTON     68  73  50  71 / 100  90  20   0
FLORENCE       62  73  49  72 / 100  40   5   0
LUMBERTON      62  72  49  71 / 100  40  10   0
MYRTLE BEACH   67  73  51  70 / 100  70  10   0

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
SC...NONE.

PUBLIC...TRA
MARINE...TRL

HAZARDOUS WEATHER OUTLOOK...UPDATED TO INCREASE RIP CURRENT RISK
NATIONAL WEATHER SERVICE WILMINGTON NC
550 AM EDT SUN MAY 2 2004

NCZ087-096-097-099>101-SCZ017-023-024-032>034-039-046-021150-
BLADEN-BRUNSWICK-COLUMBUS-DARLINGTON-DILLON-FLORENCE-GEORGETOWN-
HORRY-MARION-MARLBORO-NEW HANOVER-PENDER-ROBESON-WILLIAMSBURG-
550 AM EDT SUN MAY 2 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHEASTERN NORTH CAROLINA
AND NORTHEASTERN SOUTH CAROLINA.

.DAY ONE...TODAY AND TONIGHT

THERE IS A HIGH RISK FOR RIP CURRENTS TODAY FOR THE SOUTH AND
SOUTHEAST FACING BEACHES. THE REMAINDER OF THE BEACHES WILL HAVE A
MODERATE RISK OF RIP CURRENTS TODAY.

THUNDERSTORMS WILL DEVELOP THIS AFTERNOON AND CONTINUE THROUGH
TONIGHT AS A COLD FRONT MOVES SLOWLY EAST ACROSS THE CAROLINAS.  SOME
OF THESE THUNDERSTORMS COULD BECOME STRONG LATE THIS AFTERNOON OR
EVENING...PRODUCING GUSTY WINDS NEAR SEVERE LIMITS...MAINLY WELL
INLAND.  LOCALLY HEAVY RAINFALL IS POSSIBLE TONIGHT...AND MAY CAUSE
PONDING OF WATER IN LOW LYING AREAS...ESPECIALLY NEAR THE COAST WHERE
HEAVY RAINS FELL ON SATURDAY.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

THUNDERSTORMS WILL CONTINUE INTO MONDAY MORNING...AND MAY PRODUCE
LOCALLY HEAVY RAINFALL.

.SPOTTER CALL TO ACTION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED LATE THIS AFTERNOON OR TONIGHT.

RAS