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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KILM 060202 AAA
AFDILM

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE WILMINGTON NC
902 PM EST WED MAR 5 2014

.SYNOPSIS...
A STRONG LOW PRESSURE SYSTEM WILL MOVE ACROSS FLORIDA THURSDAY...
INTENSIFYING AS IT MOVES OFF THE CAROLINA COAST THURSDAY NIGHT AND
FRIDAY. WINDY...CLOUDY...COLD AND WET CONDITIONS WILL CONTINUE
THROUGH FRIDAY AS A RESULT OF THE LOW. HIGH PRESSURE WILL BUILD IN
FOR THE WEEKEND WITH MUCH WARMER WEATHER EXPECTED SATURDAY THROUGH
THE MIDDLE OF NEXT WEEK. ANOTHER STORM SYSTEM MAY AFFECT THE AREA AT
THE END OF THE UPCOMING WEEK.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
-- Changed Discussion --
AS OF 745 PM WEDNESDAY...LATEST 88D ILLUSTRATES THE EXITING OF
THE MAIN AREA OF PCPN NE OF THE ILM CWA. RESIDUAL LOW CHANCE FOR
VERY LIGHT RAIN OR DRIZZLE WILL EXIST ACROSS MAINLY COASTAL
LOCATIONS WITHIN THE ILM CWA THRU MIDNIGHT. LOOKING AT THE LATEST
SAT IMAGERY TRENDS...IR 11-3.9 MICRON CHANNEL...TEMPORARY PARTIAL
CLEARING WILL OCCUR ACROSS THE NW PORTIONS OF THE ILM CWA THIS
EVENING. HOWEVER...FURTHER UPSTREAM ALONG WITH 18Z MODELS INDICATE
THE RAPID RETURN OF HIGH LEVEL AND EVENTUALLY MID LEVEL CLOUDINESS
FROM THE SW DURING THE PRE-DAWN THU HOURS. AFTER MIDNIGHT...
LOW LEVEL CLOUDS DEVELOPING LITERALLY OVERHEAD ACROSS THE FA IN
RESPONSE TO DECENT OVERRUNNING LOW LEVEL MOISTURE. WITH DYNAMICS
ALOFT PUSHING IN FROM THE SW...EXPECT INCREASING POPS TOWARD
DAYBREAK THU WITH THE HIGHEST POPS ACROSS THE SW PORTIONS OF THE
ILM CWA...AND LOWEST NE PORTIONS. NO PCPN TYPE ISSUES
EXPECTED...EVEN-THOUGH SFC TEMPS WILL BE CLOSE TO THE FREEZING
MARK. STRONG 1040+ MB ARCTIC/POLAR HIGH PRESSURE CENTERED OVER SE
CANADA WILL WEDGE/RIDGE SOUTHWARD ACROSS THE CAROLINAS LATER
TONIGHT AND INTO THE SHORT TERM PERIOD. THERE IS CAA THAT OCCURS
ACROSS THE FA OVERNIGHT DUE TO THIS WEDGE...WITH THE BEST OF THIS
COLD SURGE TO BE FELT ACROSS THE CENTRAL AND WESTERN CAROLINAS.
NEVERTHELESS...WILL HAVE TO MONITOR OVERNIGHT TEMPS SINCE THE
INLAND PORTIONS OF THE FA WILL BE IN THE NEIGHBORHOOD OF 32
DEGREES. AS FOR LOW TEMPS TONIGHT...THE GFS MOS GUIDANCE IS TOO
LOW...THE NAM MOS GUIDANCE TOO MILD. HAVE BASICALLY STAYED
COMPROMISED BETWEEN THE 2...WHICH STILL PAINTS A FEW 32 DEGREE MIN
TEMPS ACROSS THE FA.

FOR CLIMATE AFICIONADOS...A COUPLE OF TODAYS LOW HIGH
TEMPERATURES EITHER TIED OR SET NEW RECORDS FOR THIS DATE.
THEY INCLUDE...

NEW RECORD OF 41 NORTH MYRTLE BEACH SC...OLD RECORD 46 SET IN 2002.
TIED RECORD 41 LUMBERTON NC...OLD RECORD 41 SET IN 1957.

PREVIOUS DISCUSSION..........................................
AS OF 245 PM WEDNESDAY...AS AN UPPER LEVEL IMPULSE PUSHES
OVERHEAD AND OFFSHORE THIS EVENING...DRY MID-LEVEL AIR SHOULD END
THE WIDESPREAD LIGHT RAIN THAT HAS PLAGUED EASTERN SOUTH CAROLINA
AND SE NORTH CAROLINA MUCH OF THE DAY. RAIN SHOULD END ACROSS THE
SC PEE DEE REGION BY 5 PM...THE GRAND STRAND BY 7 PM...AND ACROSS
THE CAPE FEAR REGION NO LATER THAN 8-9 PM. IN THE WAKE OF THE
DISTURBANCE SKIES MAY ACTUALLY BECOME PARTIALLY CLEAR FROM
FLORENCE AND WHITEVILLE NORTH THROUGH ELIZABETHTOWN BUT IT IS
DOUBTFUL THE CLEARING LINE WILL MAKE IT MUCH CLOSER TO THE COAST
AS NORTHEAST LOW LEVEL FLOW SHOULD KEEP LOW CLOUDS SOLID FOR
WILMINGTON AND MYRTLE BEACH TONIGHT.

1041 MB ARCTIC HIGH PRESSURE CENTERED NORTH OF THE GREAT LAKES WILL
SURGE SOUTHWARD THROUGH THE INTERIOR CAROLINAS TONIGHT. GFS MODEL
PRESSURE RISES BETWEEN 00-12Z TONIGHT RANGE FROM 6-8 MB ACROSS THE
NC COASTAL PLAIN. THIS SHOULD PRODUCE A RENEWED SURGE OF NORTHERLY
WINDS ADVECTING COLD AIR SOUTHWARD WITHIN A THIN LAYER BARELY 1000
FEET THICK. LAST NIGHT`S MODELS APPARENTLY DID NOT SHOW THIS
POTENTIAL SO I HAVE MADE SIGNIFICANT DOWNWARD ADJUSTMENTS TO OUR LOW
TEMPERATURE FORECASTS AND OVERNIGHT POPS. LOWS ARE NOW EXPECTED TO
FALL TO FREEZING ALONG AND NORTH OF A LINE FROM DARLINGTON AND
FLORENCE TO MARION...THROUGH WHITEVILLE AND BURGAW.

LATE TONIGHT ISENTROPIC LIFT SHOULD BEGIN TO INCREASE ACROSS COASTAL
GEORGIA AND SOUTHERNMOST SOUTH CAROLINA AHEAD OF THE LOW COMING UP
FROM THE GULF. ODDS ARE PRECIPITATION WILL REMAIN SOUTH OF OUR
FORECAST AREA UNTIL AFTER DAYBREAK BUT I AM KEEPING SMALL (20-30
PERCENT) POPS IN NE SOUTH CAROLINA SOUTH OF FLORENCE AND MARION LATE
TONIGHT.

THE 12Z GFS IS THE PREFERRED MODEL FOR TONIGHT AS IT APPEARS THE 12Z
NAM IS TOO WARM AND SHOWS TOO MUCH LOW-LEVEL MOISTURE.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
AS OF 245 PM WEDNESDAY...ACTIVE SOUTHERN STREAM WILL CONTINUE
INTO THE SHORT TERM PERIOD AS THE SECOND MORE POTENT SYSTEM
IMPACTS THE FORECAST AREA. THE SHORTWAVE...CURRENTLY OVER
TX...WILL BECOME CLOSED AS IT APPROACHES THE REGION THURSDAY. THE
GFS/NAM ARE IN DECENT AGREEMENT WITH THE HANDLING OF THE H5 LOW
BUT THE GFS APPEARS A TOUCH TOO FAST WITH ITS PROGRESSION AND THE
NAM TOO SLOW. AT THE SURFACE...LOW PRESSURE WILL EVOLVE OFF THE
SOUTHEAST U.S. COAST AND IT WILL LIFT NORTH-NORTHEAST TO LIKELY
JUST EAST OF CAPE (NOT AS FAR EAST AS THE GFS INDICATES) BY EARLY
FRIDAY EVENING. THE PROGRESSION OF THE LOW SUGGESTS BACKING WINDS
AS IT PIVOTS BY...THUS SUBSEQUENTLY FAVOR UNDERCUTTING GUIDANCE A
BIT FOR MOST OF THE FORECAST AREA.

OVERALL RAINFALL AMOUNTS FROM THIS SYSTEM ARE IMPRESSIVE WITH QPF UP
TO 2 INCHES. AFTER THE PAUSE BETWEEN TODAY/S WAVE AND THE
APPROACHING SYSTEM ISENTROPIC LIFT WILL CONTINUE TO INCREASE DURING
THURSDAY MORNING AS WILL THE PRECIPITABLE WATER. IN ADDITION...
LOW-LEVEL CONVERGENCE AND SUPPORT FROM THE JET ALOFT WILL RESULT IN
DECENT UPWARD VERTICAL VELOCITIES THROUGH FRIDAY. AFTER THE SURFACE
LOW MOVES BY THE H5 LOW WILL TRANSLATE OVERHEAD FRIDAY NIGHT. H7-H5
LAPSE RATES WILL STEEPEN TO NEARLY 6.5 TO 7 C/KM WHICH WILL SUPPORT
CONTINUING CHANCES OF RAINFALL...POSSIBLY BECOMING MORE
CONVECTIVE...FRIDAY EVENING. HOWEVER BY THAT TIME THE DEEP MOISTURE
PLUME WILL HAVE SHIFTED OFF THE COAST SO ANY SHOWERS WOULD BECOME
SCATTERED.

OTHERWISE...WINDY CONDITIONS WILL PREVAIL THROUGH THE PERIOD ALONG
WITH ROUGH SURF AND THE POTENTIAL FOR EROSION. SOME MINOR OCEAN
OVERWASH IS ALSO POSSIBLE THURSDAY NIGHT WITH THE HIGH TIDE PRIOR TO
THE WINDS BACKING TO A NORTHERLY DIRECTION.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 245 PM WEDNESDAY...SATURDAY BRINGS SOME SEASONABLE
WEATHER...FINALLY. HIGH PRESSURE BUILDS INTO THE FL BIG BEND WHILE
MID LEVEL FLOW IS ZONAL TOGETHER BRINGING NEAR FULL SUNSHINE. THEN
WE GO FROM SEASONABLE TO EVEN MILDER ON SUNDAY AS PREFRONTAL FLOW
PROVIDES SOME ADDITIONAL WAA. THERE APPEARS TO BE INSUFFICIENT
MOISTURE FLUX AHEAD OF THE FRONT FOR ITS PASSAGE TO PRODUCE ANY
MEANINGFUL RAIN CHANCES. ALSO...WITH SUCH LOW AMPLITUDE ALOFT THE
BOUNDARY WILL NOT PROVIDE MUCH IN THE WAY OF CAA FOR THE PERIOD
HEADING INTO NEXT WEEK. MODELS HAVING TROUBLE TOWARDS THE END OF THE
PERIOD AS SPLIT FLOW CONTINUES. IT DOES APPEAR THAT A POTENT LATE
WEEK SYSTEM WILL BE DEVELOPING BUT IT MAY BE JUST AFTER THE VALID
LONG TERM PERIOD BEFORE IT AFFECTS US.

&&

.AVIATION /02Z THURSDAY THROUGH MONDAY/...
AS OF 00Z...MVFR/IFR ALONG THE COAST OVERNIGHT WITH VFR/MVFR INLAND.
RAIN CHANCES INCREASE AGAIN ON THURSDAY WITH MVFR/IFR DUE TO LOW
CIGS PERSISTING THROUGH THE REMAINDER OF THE VALID TAF PERIOD.

AS NORTH-NORTHEAST WINDS 5-10 KTS PERSIST THIS EVENING...LATEST
RADAR IMAGERY DEPICTS SOME AREAS OF -DZ ALONG THE COAST...QUICKLY
PUSHING OFFSHORE. CONDITIONS WILL REMAIN DRY OVERNIGHT...THOUGH LOW
CIGS ARE EXPECTED TO PERSIST ALONG THE COAST...WITH INTERMITTENT
PERIODS OF VFR POSSIBLE. INLAND...ANTICIPATE VFR BUT COULD
POSSIBLY SEE MVFR AT TIMES DUE TO LOW CIGS INTO THE EARLY MORNING
HOURS. GIVEN INCREASED WINDS OVERNIGHT...DO NOT ANTICIPATE FOG.
AFTER DAYBREAK...LOW PRESSURE OFFSHORE MOVES TOWARDS THE AREA AND
RAIN CHANCES WILL INCREASE...CONTINUING THROUGHOUT THE DAY.
ANTICIPATE MVFR/IFR THROUGHOUT THE DAY DUE TO LOWERED CIGS. AS FOR
WINDS...EXPECT NORTHEAST WINDS TO INCREASE TO AOB 15 KTS WITH
GUSTS UP TO 20-25 KTS BY THE AFTERNOON HOURS.

EXTENDED OUTLOOK...MVFR/IFR CONDITIONS EXPECTED THROUGH FRIDAY AS A
SERIES OF LOWS FORM ALONG THE EASTERN SEABOARD. VFR SATURDAY. SLIGHT
CHANCE FOR SHOWERS SUNDAY. VFR MONDAY.

&&

.MARINE...
-- Changed Discussion --
NEAR TERM /THROUGH TONIGHT/...
AS OF 745 PM WEDNESDAY...SCA CONDITIONS TONIGHT...WILL INCREASE TO
GALE CONDITIONS BY THU AFTERNOON AND CONTINUE THRU THU NIGHT.
UPDATED MARINE WEATHER MESSAGE ISSUED TO SHOW THE TIMING AND
CHARACTERISTICS OF BOTH WINDS/SEAS DURING THE NEXT 24 TO 36 HRS.

HIGH PRESSURE WEDGING SOUTHWARD ACROSS THE CENTRAL CAROLINAS FROM
ITS 1040+ MB CENTER LOCATED ACROSS SE CANADA...HAS NOW BECOME THE
DRIVING FORCE FOR THE OVERNIGHT N TO NE WINDS. THE SFC PG WILL RE-
TIGHTEN OVERNIGHT INTO THE SHORT TERM PERIOD...RESULTING WITH
INITIAL 15 TO 20 KT WIND SPEEDS...INCREASING TO 20 TO 25 KT WITH
POSSIBLE GUSTS UP TO 30 KT LATE IN THE PRE-DAWN THU HOURS. WITH
SOME CAA TO OCCUR...A FLUCTUATION IN WIND SPEEDS WILL OCCUR EARLY
ON...BUT SHOULD BECOME MORE STEADY AS THE NIGHT PROGRESSES DUE
TO THE TIGHTENING OF THE SFC PG. SIGNIFICANT SEAS WILL BE AT
THEIR LOWEST THIS EVENING...WITH A SLOW GRADUAL BUILDING TREND
OVERNIGHT INTO THE SHORT TERM. LOOKING AT 3 TO 7 FT BY DAYBREAK
THU. HIGHEST SEAS OFF CAPE FEAR AND OFF THE MOUTH OF WINYAH BAY.
THE LOWER SEAS TO OCCUR JUST WEST OF FRYING PAN SHOALS...AND THE
NEAR SHORE WATERS SOUTH OF CAPE FEAR TO MYRTLE BEACH. AVERAGE
PERIODS BETWEEN 4.5 AND 5.0 SECONDS.

PREVIOUS DISCUSSION.................................................
AS OF 245 PM WEDNESDAY...WEAK LOW PRESSURE ABOUT 250 MILES SOUTH-
SOUTHEAST OF CAPE FEAR WILL SLIP EASTWARD ALONG A STALLED FRONT
TONIGHT. THE BIGGER STORY WILL BE A SPRAWLING 1041 MB ARCTIC HIGH
PRESSURE JUST NORTH OF THE GREAT LAKES. THIS HIGH WILL SURGE
SOUTHWARD THROUGH THE INTERIOR CAROLINAS TONIGHT. 12-HOUR PRESSURE
RISES 6 TO 8 MILLIBARS ACROSS THE NC COASTAL PLAIN SHOULD BE
SUFFICIENT TO PUSH WINDS ON THE COASTAL WATERS UP TO 20-25 KNOTS BY
LATE THIS EVENING...WITH SEAS BUILDING TO 5-7 FT LATE. NORMALLY THIS
WOULD NECESSITATE A SMALL CRAFT ADVISORY...BUT SINCE CONDITIONS
SHOULD DETERIORATE FURTHER TOMORROW AS LOW PRESSURE DEVELOPS TO OUR
SOUTH WE WILL GO AHEAD AND RAISE A GALE WARNING THIS EVENING
EXTENDING THROUGH TOMORROW. AMONG 12Z MODEL GUIDANCE...THE GFS IS
PREFERRED OVER THE NAM.

SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 245 PM WEDNESDAY...THE GALE WATCH HAS BEEN UPGRADED TO A
WARNING FOR MARGINAL GALE CONDITIONS. NORTHEASTERLY WINDS WILL
LIKELY PEAK THURSDAY NIGHT THEN THEY WILL SLOWLY BACK TO THE
NORTHWEST BY FRIDAY NIGHT AS THE LOW PASSES BY THE WATERS. ONLY MADE
A FEW TWEAKS TO SWAN OUTPUT...FOCUSING THE HIGHEST WAVES AWAY FROM
THE COAST OFF CAPE FEAR THURSDAY NIGHT. WIDESPREAD RAINFALL EXPECTED
AND POSSIBLY SOME CONVECTION FRIDAY NIGHT AS THE UPPER LOW PASSES
OVERHEAD.

LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 245 PM WEDNESDAY...OFFSHORE WINDS GROW LIGHTER ON MONDAY AS
HIGH PRESSURE PROGRESSES INTO THE PANHANDLE/BIG BEND OF FL
PENINSULA. THE GRADIENT REMAINS FAIRLY WEAK ON SUNDAY DESPITE THE
APPROACH OF A COLD FRONT THAT WILL MOVE THROUGH ON SUNDAY. THERE
WILL BE NO REAL PUSH OF COOL AIR BEHIND THE BOUNDARY COME MONDAY SO
A CONTINUED LIGHT OFFSHORE FLOW IS EXPECTED. SEAS WILL EXHIBIT A
VERY STEADY AND GRADUAL ABATING TREND THROUGH THE PERIOD.
-- End Changed Discussion --

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...GALE WARNING UNTIL 1 PM EST FRIDAY FOR AMZ250-252-254-256.

&&

$$
SYNOPSIS...SRP
NEAR TERM...DCH/TRA
SHORT TERM...SRP
LONG TERM...MBB
AVIATION...SGL