000
FXUS62 KILM 240534
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
1235 AM EST TUE NOV 24 2009

.SYNOPSIS...
CLOUDY CONDITIONS ARE EXPECTED OVERNIGHT THROUGH TUESDAY AS
RESIDUAL MOISTURE IS LIFTED OVER COOL AIR NOSING SOUTH FROM NEW
ENGLAND. LOW PRESSURE DEVELOPING EARLY WEDNESDAY OVER FLORIDA WILL
MOVE NORTHEAST ALONG THE CAROLINA COAST THURSDAY. THIS LOW WILL BE
CLOSELY FOLLOWED BY A COLD FRONT THAT WILL USHER IN COLDER AIR FOR
THE WEEKEND...ALONG WITH THE POTENTIAL FOR FROST OR FREEZING
CONDITIONS. 

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 930 PM MONDAY...SFC LOW HAS INCHED ITS WAY NE TO CAPE HATTERAS 
WITH MOIST SFC N TO NW FLOW BEHIND IT TO ENCOMPASS THE AREA. HOURLY 
NAM AND 3-HOURLY GFS BUFR SOUNDINGS KEEP MOISTURE TRAPPED ROUGHLY 
BELOW 1500 FEET DURING THE OVERNIGHT. SOUNDINGS EXHIBIT MORE OF A 
LOW STRATUS CLOUD EVENT OVERNITE ACROSS THE ILM CWA THEN WIDESPREAD 
DENSE FOG AT THIS TIME. AS A RESULT...WILL CONTINUE WITH THE CLOUDY 
SKY CONDITIONS WITH AREAS OF FOG WITH POSSIBLE LIGHT DRIZZLE. ONLY 
TRACE QPF AT MOST EXPECTED FROM THE DRIZZLE AND WILL THEREFORE NOT 
EXHIBIT A POP. MIN TEMPS LOOK ON TARGET AND SEE NO REASON TO TWEAK. 
DUE TO THE TIGHTENED SFC PRESSURE PATTERN AROUND THE SFC LOW...
THE WIND DIRECTION/SPEED WILL NEED TWEAKING ACROSS LAND AREAS WITH 
SPEEDS BASICALLY 5 MPH...OR LESS WEST OF I-95.      

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 3 PM MONDAY...MODELS ARE NOT IN AGREEMENT WITH HOW TO HANDLE
THIS PORTION OF THE FORECAST. ALL GUIDANCE INCLUDING THE CANADIAN
AND ECMWF WAS PERUSED AND TWO CAMPS OF MODEL SOLUTIONS ARE
EVIDENT. MOST OF THE GUIDANCE SHOWS LOW PRESSURE DEVELOPING OVER
FLORIDA EARLY WEDNESDAY...TRACKING UP THE SOUTHEAST COAST AND
SPREADING A BAND OF GENERALLY LIGHT RAIN INTO THE COASTAL COUNTIES
WEDNESDAY INTO WEDNESDAY NIGHT. THE NAM SHOWS A MUCH WEAKER AND
FARTHER EAST LOW WHICH DOES NOT SPREAD MOISTURE FAR ENOUGH WEST TO
HAVE ANY IMPACT ON OUR WEATHER. THIS EXPLAINS THE NAM MOS GUIDANCE
SHOWING MUCH DRIER AND COOLER WEATHER...ESPECIALLY ON WEDNESDAY.

HPC SUGGESTS...AND WE AGREE...THAT THE NAM IS LIKELY AN OUTLIER
AND THAT THE LOW WILL INDEED TRACK CLOSE ENOUGH TO THE COAST TO
SPREAD SOME RAIN INLAND. OUR FORECAST IS THEREFORE LITTLE CHANGED
FROM THE PREVIOUS SHIFT. PRECIPITATION CHANCES WEDNESDAY INTO
WEDNESDAY NIGHT WILL RANGE FROM 40% ALONG THE COAST TO 20% ON THE
I-95 CORRIDOR. OFFSHORE RAIN CHANCES ARE BETTER THAN 50/50.

DAY/NIGHT TEMPERATURE RANGES WILL BE COMPRESSED DUE TO PLENTY OF
CLOUD COVER EXPECTED. EVEN TUESDAY SHOULD REMAIN CLOUDY DUE TO
RESIDUAL EFFECTS FROM THE COLD AIR WEDGE. OUR TEMPERATURE
FORECASTS ARE VERY CLOSE TO THE GFS MOS GIVEN ITS CLOUDIER OUTLOOK
COMPARED TO THE NAM.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 3 PM MONDAY...HIGH AMPLITUDE MID TO UPPER TROUGH WILL DIG DOWN 
FROM THE GREAT LAKES DOWN TO THE GULF COAST THURS INTO FRI WHILE IT 
PUSHES EASTWARD THROUGH TIME ACROSS THE EASTERN CONUS. THIS SYSTEM 
WILL PUSH A STRONG COLD FRONT THROUGH ON THURS. A COASTAL TROUGH/LOW 
OFF THE NORTH CAROLINA COAST THURS MORNING COULD INITIALLY PROVIDE 
SOME EARLY PCP ON THURS BUT WILL MOVE OFF TO THE NORTHEAST AS FRONT 
MOVES OFF SHORE. THEREFORE ALL WEATHER WILL CLEAR OUT THROUGH THURS 
LEAVING PLENTY OF COOL AND DRY AIR IN PLACE. A VERY SHARP GRADIENT 
WILL EXIST INITIALLY WITH PCP WATER VALUES UP OVER AN INCH ALONG THE 
COAST AND LESS THAN A HALF INCH INLAND...BUT BY THURS EVENING A 
STRONG WESTERLY FLOW ALOFT WILL CARRY PLENTY OF DRY AIR INTO THE 
CAROLINAS. WILL SEE PCP WATER VALUES DOWN TO LESS THAN A QUARTER OF 
AN INCH BY FRI MORNING. ONCE COLD FRONT MOVES THROUGH ON THURS 
PLENTY OF DRY AND COLD AIR WILL MOVE IN BEHIND IT WHILE H5 LOW STILL 
REMAINS BACK OVER THE GREAT LAKES KEEPING W-SW FLOW ALOFT. ONCE THE 
MID TO UPPER TROUGH SWINGS THROUGH ON FRI...DEEP LAYER NW FLOW WILL 
REINFORCE CAA FRI THROUGH SAT. NORTHWEST FLOW WILL CONTINUE INTO SAT 
ON FRONT END OF HIGH PRESSURE SYSTEM. LOW LEVEL THICKNESSES TAKE A 
DEEP PLUNGE LATE THURS INTO FRI MORNING FROM NEAR 1370 THURS AFTN 
DOWN TO LESS THAN 1320 BY FRI MORNING AND THEN CONTINUE A GRADUAL 
DECLINE EVEN FURTHER TO AROUND 1310 BY SAT MORNING. 850 TEMPS DROP 
BELOW 0C FRI MORNING AND REMAIN BELOW THROUGH EARLY SAT. THEREFORE 
TEMPS WILL START OUT AT OR ABOVE CLIMO...IN THE MID 60S ON THURS 
BEFORE A COOLING TREND BEGINS BEHIND COLD FRONT. TEMPS THURS NIGHT 
MAY STAY A LITTLE WARMER IN THE 40S MOST PLACES...BUT BY FRI PLENTY 
OF COLD AND DRY AIR WILL BRING DEW POINT TEMPS DOWN TO THE LOWER 30S 
BY FRI NIGHT. HIGHS ON FRI WILL MOST LIKELY NOT MAKE IT OUT OF 50S 
WITH CAA IN FULL SWING. BY FRI NIGHT TEMPS WILL DROP INTO THE 30S.

HIGH PRESSURE WILL MIGRATE EASTWARD THROUGH SAT AS STRONG RIDGE 
BUILDS ALOFT. THIS SHOULD HELP MODERATE TEMPS HEADING INTO THE 
SECOND HALF OF THE WEEKEND AND EARLY NEXT WEEK. ALTHOUGH BEST CAA 
WILL END BY SAT MORNING CLEAR SKIES AND CALM WINDS WILL PRODUCE 
IDEAL RADIATIONAL COOLING CONDITIONS SAT NIGHT KEEPING TEMPS DOWN 
IN THE 30S ONCE AGAIN. HIGH TEMPS SAT SHOULD BEGIN TO MODIFY BUT 
WITH SUCH A COOL START EXPECT HIGHS IN 50S IN MOST PLACES ONCE 
AGAIN. 

WILL CONTINUE ON A WARMING TREND THROUGH SUN WITH PLENTY OF SUNSHINE 
EXPECT TEMPS BACK TOWARD NORMAL...IN THE MID 60S. ANOTHER COOL NIGHT 
SUN NIGHT DOWN IN THE 40S AND THEN AS HIGH SLIPS OFF SHORE A WARMER 
RETURN FLOW SETS UP THROUGH MONDAY. AFTER A VERY DRY PERIOD FROM FRI 
THROUGH SUN...CHANCES OF PCP WILL START TO ENTER BACK IN THE PICTURE 
MON INTO TUES AS MOISTURE INCREASES IN RETURN FLOW BETWEEN NEXT 
STORM SYSTEM APPROACHING FROM THE WEST AND HIGH PRESSURE TO THE
EAST.

&&

.AVIATION /06Z MONDAY THROUGH SATURDAY/...
WEDGE OF HIGH PRESSURE WILL REMAIN THROUGH THE END OF THE FORECAST 
PERIOD KEEPING CEILINGS IFR OR LOWER. ANY SLIGHT IMPROVEMENT IN 
CEILINGS DURING THE AFTERNOON WILL LOWER AGAIN TO LIFR/IFR SHORTLY 
AFTER SUNSET.

EXTENDED OUTLOOK...IFR CEILINGS/VISIBILITIES WILL CONTINUE THROUGH 
WEDNESDAY MORNING. IMPROVING CONDITIONS WEDNESDAY AFTERNOON.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 930 PM MONDAY...NO ADVISORIES OR CAUTIONS THIS GO AROUND. 
THE SFC LOW HAS MOVED TO THE VICINITY OF CAPE HATTERAS WITH A SLIGHT 
TIGHTENING OF THE SFC PG VIA LATEST MSAS. AS A RESULT...HAVE 
SLIGHTLY INCREASED THE NW WINDS OVERNIGHT WITH ITS EFFECTS BASICALLY 
AIDING IN CONTINUING TO KNOCK DOWN THE ONCE PROFOUND SEAS. MAIN 
CONCERN FOR MARINERS WILL BE CLOSER TO THE IMMEDIATE COAST VIA 
INLETS TO/FROM THE ATLANTIC...THE INTRA-COASTAL WATERWAY AND INLAND 
BAYS AND SOUNDS WHERE THE LOW STRATUS CLOUDINESS AND POSSIBLY AREAS 
OF FOG COULD HAMPER ALL MARITIME NAVIGATION.    

SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 3 PM MONDAY...HIGH PRESSURE OVER NEW ENGLAND WILL EXTEND
DOWN THE U.S. EAST COAST TUESDAY MORNING...BUT WILL LOSE ITS
INFLUENCE LATER IN THE DAY AS LOW PRESSURE BEGINS TO ORGANIZE OVER
CENTRAL FLORIDA. THIS LOW IS EXPECTED TO TRACK NORTHEASTWARD AND
JUST OFF THE NC/SC COAST WEDNESDAY AND WEDNESDAY NIGHT. ALTHOUGH
THERE IS SIGNIFICANT SPREAD IN MODEL SOLUTIONS...IT APPEARS WINDS
WILL NOT INCREASE BEYOND 15 KNOTS AT ANY POINT TUESDAY THROUGH
WEDNESDAY NIGHT...WITH DIRECTIONS VARYING FROM NORTHEAST THROUGH
NORTHWEST. MUCH FARTHER OFFSHORE...CONDITIONS WILL BE MUCH
STORMIER AND WE ARE EXPECTING CONSIDERABLE BACKSWELL TO THE MOVING
INTO THE CAROLINA COASTAL WATERS WITH SEAS BUILDING TO 3-5 FT.

LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 3 PM MONDAY...COASTAL TROUGH/LOW OFF NORTH CAROLINA COAST 
MAY PRODUCE TRICKY FORECAST FOR WINDS THURS MORNING...BUT MOST
WATERS SHOULD START OUT WITH NORTHERLY WINDS. OVERALL EXPECT LIGHT
OFF SHORE FLOW OR NORTHERLY THROUGH EARLY THURS WITH SEAS LESS
THAN 3 FT. BY THURS AFTERNOON A STRONG COLD FRONT WILL MOVE
THROUGH THE WATERS WITH DECENT COLD SURGE BEHIND IT. THEREFORE
EXPECT WINDS AND SEAS TO INCREASE FURTHER THROUGH THURS AFTN INTO
FRI IN COLD SURGE AND ENHANCED GRADIENT FLOW. MAY SEE SEAS UP NEAR
4 TO 5 FT IN OUTER WATERS IN STRONGER W-NW FLOW THURS NIGHT
THROUGH EARLY SAT...WITH WINDS GREATER IN COLDER AIR IN WELL MIXED
ATMOSPHERE OVERNIGHT. AS HIGH PRESSURE MIGRATES EASTWARD THROUGH
SAT WINDS WILL LIGHTEN UP AND BECOME MORE VARIABLE THROUGH SAT
NIGHT WITH SEAS DECREASING TO LESS THAN 2 FT BY END OF PERIOD.

&&

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

&&

$$

SYNOPSIS...TRA
NEAR TERM...DCH
SHORT TERM...TRA
LONG TERM...RGZ
AVIATION...43/RJD