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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KILM 092312
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
610 PM EST TUE FEB 9 2010

.SYNOPSIS...
A DEVELOPING AREA OF LOW PRESSURE OFF THE CAROLINA COAST WILL
MOVE NORTHEAST OF THE AREA THIS EVENING BEFORE BEGINNING TO
RAPIDLY INTENSIFY LATE TONIGHT AND WEDNESDAY. THIS WILL CREATE A
VERY TIGHT PRESSURE GRADIENT ACROSS THE AREA WHICH WILL LINGER
INTO THURSDAY AS THE STORM DEEPENS FURTHER SOUTHEAST OF NEW
ENGLAND. THE NEXT IN THE PARADE OF LOW PRESSURE SYSTEMS WILL MOVE
BY TO OUR SOUTH FRIDAY NIGHT AND SATURDAY BRINGING A CHANCE OF
SNOW. HIGH PRESSURE WILL BUILD IN FOR THE LATTER HALF OF THE
WEEKEND.

&&

.UPDATE...
-- Changed Discussion --
AS OF 6 PM...WE HAVE UPDATED THE PUBLIC GRIDS/ZONE FORECASTS TO
INCLUDE THE POTENTIAL OF LOCALIZED DENSE FOG FOR THE NEXT SEVERAL
HOURS IN THE CAPE FEAR REGION. LIGHT WINDS WITHIN THE CENTER OF THE
DEVELOPING SURFACE LOW COMBINED WITH HIGH HUMIDITY FROM THE EARLIER
RAINFALL WILL HELP CREATE THIS POTENTIAL. ONCE THE SURFACE LOW EDGES
OFFSHORE IN A FEW HOURS SOUTHWESTERLY WINDS WILL HELP TO MIX THE FOG
OUT. THE ARCTIC FRONT APPROACHING FROM THE WEST AFTER MIDNIGHT WILL
BRING SHARPLY DRIER AIR IN ON EVEN STRONGER WESTERLY WINDS.

VISIBILITIES COULD DROP BELOW ONE QUARTER MILE AT TIMES ACROSS
BURGAW...WILMINGTON...LELAND...BOLIVIA...WHITEVILLE AND
ELIZABETHTOWN THROUGH ABOUT 9 PM...WITH IMPROVING CONDITIONS THEN
EXPECTED.
-- End Changed Discussion --

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
AS OF 3 PM TUESDAY...HEAVIEST RAIN CONTINUES TO SHIFT NE AS
CONSOLIDATING LOW PRESSURE NEAR CAPE FEAR SLOWLY MOVES TO THE NE.
THIS AREA OF LOW PRESSURE WILL BE N OF CAPE LOOKOUT THIS EVE AND
WILL INTENSIFY RAPIDLY LATE TONIGHT AND ON WED...SIGNIFICANTLY
TIGHTENING THE PRESSURE GRADIENT ACROSS THE EASTERN CAROLINAS.
ANY RISK OF THUNDERSTORMS ACROSS CAPE FEAR REGION WILL QUICKLY END
MID TO LATE AFTERNOON. STILL CAN NOT REMOVE MENTION OF PRECIPITATION
UNTIL THE COLD FRONT SWEEPS FROM W TO E ACROSS OUR AREA 04-08Z.
HOWEVER...ADDITIONAL QPF AFTER 22Z WILL BE LIGHT. WINDS WILL SHIFT
FROM SW TO WNW WITH FRONTAL PASSAGE AND WIND SPEEDS WILL INCREASE
SHARPLY AS MAGNITUDE OF COLD AND DRY AIR INCREASES. HIGHER MOMENTUM
AIR ALOFT WILL REACH THE SURFACE AS MIXED LAYER INCREASES IN DEPTH
TOWARD DAYBREAK WED. TEMPS WILL NOT CHANGE MUCH THIS EVE...BUT WILL
FALL SHARPLY WITH THE PASSAGE OF THE COLD FRONT AFTER MIDNIGHT.
TEMPS IN THE MID AND UPPER 30S AT DAYBREAK WILL COMBINE WITH THE
STRONG WINDS TO MAKE IT FEEL AS IF IT WERE WELL DOWN IN THE 20S.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
AS OF 3 PM TUESDAY...COLD AND WINDY CONDITIONS CAN BE EXPECTED ON
WEDNESDAY AS LOW PRESSURE SYSTEM DEEPENS OFF THE MID ATLANTIC
COAST. WINDS QUICKLY REACH UP TO 35 TO 40 KTS JUST ABOVE THE
SURFACE EARLY WED MORNING. AS MIXING OCCURS THROUGH THE DAY EXPECT
GUSTS TO EASILY REACH THIS HIGH AND SUSTAINED WINDS UP AROUND 25
TO 30 KTS. WILL JUST TIP THE SCALE IN TERMS OF A WIND ADVISORY AND
THEREFORE WILL GO AHEAD AND ISSUE ONE MAINLY TO ACCOUNT FOR THE
SATURATED SOILS ACROSS THE AREA AND POSSIBILITY OF TREES FALLING.
EXPECT MAX WINDS FOR A FEW HOURS IN THE AFTERNOON UP AROUND 25 TO
35 MPH. MOST OF THE DAY SHOULD SEE WINDS IN THE 20 TO 30 MPH WITH
GUSTS UP TO 45 MPH. WITH PLENTY OF CAA THROUGH WED TEMPS SHOULD
MAX OUT IN THE LOW 40S MOST PLACES. COMBINE THESE TEMPS WITH GUSTY
NW WINDS TO PRODUCE WIND CHILL VALUES IN THE 30S DURING WED AFTN.

AS ARCTIC HIGH PRESSURE BUILDS IN AND LOW TRACKS FARTHER OFF TO
THE NORTHEAST THROUGH WED NIGHT...THE GRADIENT WILL REMAIN FAIRLY
TIGHT. EXPECT WINDS TO AROUND 10 TO 15 MPH BY THURS MORNING.
ALTHOUGH MAX CAA WILL BE OVER BY WED NIGHT AND ATMOSPHERE WILL
REMAIN WELL MIXED...850 TEMPS WILL STILL BE DOWN WELL BELOW 0C.
EXPECT TEMPS DOWN IN THE 20S.

GRADIENT WILL WEAKEN EVEN FURTHER BY THURS BUT SHOULD STILL HAVE
COOL NORTHWEST WINDS AND TEMPS HOLDING IN THE 40S MOST PLACES. BY
THURS NIGHT UNDER BETTER RADIATIONAL COOLING CONDITIONS...TEMPS
WILL ONCE AGAIN DROP INTO THE 20S. TRADITIONALLY COOLER SPOTS
ACROSS THE AREA MAY END UP SEEING COLDER TEMPS THURS NIGHT THAN
WED NIGHT. WITH PCP WATER LESS THAN A QUARTER OF AN INCH...EXPECT
A DRY FORECAST THROUGH THE PERIOD. OVERALL WILL HAVE SUNNY DRY AND
COLD WEATHER THROUGH MID WEEK WITH TEMPS RUNNING A GOOD 10 DEGREES
BELOW NORMAL.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 3 PM TUESDAY...BROAD UPPER TROF OVER THE EAST COAST WILL BE
THE MAIN PLAYER IN THE EXTENDED. THE RESULT IN THE EASTERN CAROLINAS
WILL BE A PROLONGED PERIOD OF BELOW NORMAL TEMPERATURES...WITH
DAYTIME READINGS STRUGGLING TO CRACK 50 AND MINS GENERALLY AROUND
30.  SEVERAL NORTHERN STREAM IMPULSES WILL ROTATE THRU THIS
TROF...BUT THE FORCING WILL REMAIN TOO FAR NORTH AND MOISTURE WILL
REMAIN TOO LIMITED.  THEREFORE WILL NOT INCLUDE ANY PRECIP IN THE
EXTENDED.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
LOTS OF LOW LEVEL MOISTURE AND LIGHT WINDS FOR THE FIRST COUPLE OF
HOURS...PARTICULARLY ALONG THE COAST. FOR THIS REASON...WILL BE A
DECENT CHANCE FOR SOME MODERATE TO DENSE FOG AT THE ONSET. AFTER
02Z...WINDS WILL BEGIN TO COME IN FROM THE WEST AS LOW PRESSURE
MOVES NORTHEAST. THIS WILL MIX OUT ANY DENSE FOG IF PRESENT. AROUND
08Z...COLD AIR ADVECTION BEGINS WITH WINDS INCREASING RAPIDLY TO
AROUND 15 KTS WITH GUSTS OVER 20. BY 12Z...GOOD MIXING THROUGHOUT
THE COLUMN WILL BRING STRONG WINDS DOWN TO THE SURFACE...WITH GUSTS
OVER 35 KTS POSSIBLE THROUGHOUT THE DAY...WITH LBT AND ILM IN THE
STRONGEST GRADIENT. EXPECTED ONLY A SLIGHT DECREASE IN THE WINDS AT
THE END OF THE FORECAST PERIOD WITH VFR CONDITIONS. THERE WILL BE A
SLIGHT CHANCE OF A MVFR/VFR STRATA CU CEILING AROUND MID MORNING.

EXTENDED OUTLOOK...HIGH CONFIDENCE VFR WEDNESDAY EVENING THROUGH
FRIDAY. MEDIUM CONFIDENCE FOR PERIODS OF MVFR SATURDAY AS UPPER
LEVEL SHORT WAVE TROUGH BRINGS SHOWERS. SUNDAY STARTS VFR THEN AS
COLD FRONT APPROACHES FROM THE WEST...PERIODS OF MVFR/IFR WITH
SHOWERS.
-- End Changed Discussion --

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 3 PM TUESDAY...LOW PRESSURE WILL MOVE NE OF THE AREA THIS EVE
AND RAPIDLY INTENSIFY LATE TONIGHT AND WED. THIS WILL SIGNIFICANTLY
TIGHTEN THE PRESSURE GRADIENT ACROSS THE WATERS. WINDS WILL SHIFT
FROM SW TO WNW...AND INCREASE SHARPLY 07-09Z WITH THE PASSAGE OF A
COLD FRONT...APPROACHING FROM THE W. AS DRY AND COLD AIR SWEEP
ACROSS THE WATERS...MIXING WILL INCREASE THROUGH A DEEPENING LAYER
ALLOWING HIGHER MOMENTUM AIR TO REACH THE SURFACE. ONGOING/
DEVELOPING SMALL CRAFT ADVISORY CONDITIONS THROUGH THIS EVE WILL
TRANSITION TO GALE WARNING AFTER MIDNIGHT. SEAS WILL CONTINUE TO
BUILD THROUGH THE NIGHT. HOWEVER...SINCE THE STRONGEST WINDS WILL
OCCUR WHEN THE WIND DIRECTION IS WNW...SEAS WILL NEVER FULLY
DEVELOP. THEREFORE...SEAS WILL NOT REACH LEVELS THAT WIND SPEEDS
ALONE WOULD INDICATE. STILL WE DO EXPECT SEAS TO REACH ABOVE 6 FT
WITHIN 20 NM...HIGHEST SEAS WILL OCCUR OVERNIGHT AND WED.

SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 PM TUESDAY...WITH COLD FRONT PUSHING FARTHER OFF SHORE AND
LOW PRESSURE DEEPENING OFF THE MID ATLANTIC COAST WILL HAVE A VERY
TIGHT GRADIENT FLOW OVER LOCAL WATERS. WINDS WILL REACH GALE FORCE
IN THE OUTER WATERS IN A STRONG OFF SHORE NW FLOW. EXPECT MAX
WINDS FROM WED AFTN THROUGH EARLY EVENING UP AROUND 35 TO 40 KTS.
WITH OFF SHORE COMPONENT TO THE FLOW NEAR SHORE SEAS WILL DIMINISH
TO 3 TO 5 FT BY WED AFTN WHILE SEAS IN THE OUTER WATERS WILL BE UP
AROUND 7 TO 9 FT. SEAS WILL DIMINISH EVEN FURTHER WED NIGHT INTO
THURS REACHING DOWN TO 3 TO 5 FT THROUGH THURS MORNING AND 4 FT OR
LESS BY THURS EVENING INTO FRI MORNING.

WINDS WILL BE SLOW TO DECREASE AS GRADIENT REMAINS TIGHT THROUGH
WED NIGHT AS LOW PRESSURE DEEPENS EVEN FURTHER AS IT PASSES SOUTH
OF NEW ENGLAND. BY THURS MORNING EXPECT GALE FORCE WINDS TO BE
OVER WITH...BUT WILL STILL BE IN SCA THRESHOLDS WITH WINDS 25 TO
30 KTS. THROUGH THURS GRADIENT WILL CONTINUE TO RELAX IN AN OFF
SHORE FLOW DOWN TO 15 TO 20 KTS BY THE END OF THE DAY.

LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 3 PM TUESDAY...NOT MUCH GRADIENT TO SPEAK OF DURING THE
EXTENDED AS THE HIGH BUILDING FROM THE OHIO VALLEY IS QUITE WEAK.
NORTHERN STREAM IMPULSE WILL MOVE OFF THE MID-ATLANTIC COAST...AND
BETWEEN THAT AND THE COLD...FAIRLY DEEPLY-MIXED AIRMASS...WILL BUMP
THE WINDS TO A SOLID 15 KT SAT AFTERNOON AND EVENING. COULD SEE
WINDS BACK TO WESTERLY ON SUNDAY AS A CLIPPER LOW DIVES INTO THE
OHIO VALLEY.

OFFSHORE TRAJECTORY WILL KEEP SEAS FAIRLY WELL IN CHECK. CAPPED THE
SEAS AT 4 FT NEAR FRYING PAN BUOY AND 3 FT WITHIN 20NM.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...WIND ADVISORY FROM 8 AM TO 8 PM EST WEDNESDAY FOR SCZ017-023-
     024-032>034-039-046.

NC...WIND ADVISORY FROM 8 AM TO 8 PM EST WEDNESDAY FOR NCZ087-096-
     097-099>101.

MARINE...SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO 1 AM EST
     WEDNESDAY FOR AMZ254-256.

     GALE WARNING FROM 1 AM WEDNESDAY TO 5 AM EST THURSDAY FOR
     AMZ250-252-254-256.

     SMALL CRAFT ADVISORY UNTIL 1 AM EST WEDNESDAY FOR AMZ250-252.

&&

$$
SYNOPSIS...RGZ
NEAR TERM...RJD
SHORT TERM...RGZ
LONG TERM...RAS
AVIATION...43
MARINE...