FXUS62 KILM 301737
AFDILM
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
1237 PM EST MON NOV 30 2009
.SYNOPSIS...
A COLD FRONT WILL CROSS THE AREA THIS EVENING ACCOMPANIED BY A FEW
SHOWERS...BUT OVERALL RAIN AMOUNTS WILL BE LIGHT. HIGH PRESSURE WILL
BUILD QUICKLY INTO THE AREA LATE TONIGHT...PASSING ACROSS THE REGION
TUESDAY. LOW PRESSURE EMERGING FROM THE GULF OF MEXICO MAY BRING
MORE SIGNIFICANT RAINFALL TO THE EASTERN CAROLINAS WEDNESDAY THROUGH
EARLY THURSDAY. BUILDING HIGH PRESSURE IS EXPECTED TO OFFER UP
COOLER AND DRIER WEATHER ACROSS THE REGION LATE IN THE WEEK HEADING
INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 945 AM MONDAY...IMAGERY THIS MORNING SHOWS A SWIFT NORTHERN
STREAM SHORT-WAVE DROPPING SE INTO THE CENTRAL MISSISSIPPI VALLEY.
THIS FEATURE WILL HELP ACCELERATE A FRONTAL BOUNDARY THROUGH THE
EASTERN CAROLINAS THIS EVENING. MUCH OF THE RAIN WITH THIS FRONT
WILL FALL WEST OF THE APPALACHIANS AND SQUEEZED-OUT IN OROGRAPHICS
OVER THE UPSTREAM RIDGES TODAY. RELATIVELY DRY AIR IN PLACE LOCALLY
AND A SPEEDY FRONTAL PASSAGE WILL RESULT IN LIGHT RAIN AMOUNTS THIS
EVENING...WITH MOST LOCATIONS RECEIVING LESS THAN A TENTH OF AN INCH
WITH THIS PROGRESSIVE FEATURE IN QUICK MOVING SHOWERS. IT LOOKS LIKE
THE NC ZONES WILL BE SLIGHTLY MORE FAVORED IN THE 12Z QPF FIELDS.
LATEST DATA SUGGEST FRONTAL PASSAGE WILL OCCUR BETWEEN 7P-8P ACROSS
FAR INTERIOR LOCATIONS THIS EVENING AND AROUND MIDNIGHT TO CLEAR THE
0-20NM COASTAL WATERS. DRY NORTHERLY FLOW WILL PUNCH INTO THE AREA
THROUGH THE WEE HOURS OF TUESDAY WITH BLUSTERY NORTH WIND GUSTS TO
GREET DAYBREAK TUESDAY.
&&
.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
AS OF 300 AM MONDAY...EXPECT FAIR WEATHER ON TUESDAY WITH HIGHS
AROUND 60 AS HIGH PRESSURE CONTROLS AREA WEATHER. INCREASING CLOUDS
ARE EXPECTED TUESDAY NIGHT AS SW FLOW ALOFT RIDES OVER HIGH PRESSURE
AT THE SURFACE. RAIN IS POSSIBLE AFTER ABOUT 06Z. THERE IS SOME
DISAGREEMENT BETWEEN THE NAM AND GFS REGARDING THE TRACK OF THE LOW
WEDNESDAY. THE NAM TAKES THE LOW NORTHWARD THROUGH WESTERN
TENNESSEE TOWARD CENTRAL OHIO WHILE THE GFS RUNS THE LOW UP THE
SPINE OF THE APPALACHIANS INTO WEST-CENTRAL PA. THIS DIFFERENCE
COULD HAVE SIGNIFICANT IMPACTS ON THE WEATHER WEDNESDAY AND
WEDNESDAY NIGHT.
THE MORE EASTWARD TRACK AND DEEPER CENTRAL PRESSURE OF THE GFS WOULD
LIKELY RESULT IN AN INITIAL ONSET OF RAIN WITH A TRANSITION TOWARD
CONVECTION AND A SEVERE WEATHER EVENT IN THE LATE AFTERNOON AND
NIGHT WEDNESDAY. THE MODEL FORECASTS A LOW LEVEL JET IN EXCESS OF
60 KT WITH OUR AREA IN THE WARM SECTOR. SHOULD THE LOW TRACK
FARTHER WEST AS IN THE NAM...ITS POSSIBLE THAT WE COULD REMAIN IN
THE COOL SECTOR AS AN IN-SITU DAMMING EVENT SETS UP WITH CONFLUENT
FLOW AT H5 OVER THE NE U.S. AT PRECIPITATION ONSET. IF THERE WERE
SEVERE WEATHER IN THIS CASE...IT WOULD LIKELY BE ALONG A COASTAL
FRONT WITH LITTLE INLAND PENETRATION.
THE PRESENT FORECAST FOR WEDNESDAY AND WEDNESDAY NIGHT MORE CLOSELY
RESEMBLES THE GFS WITH A RAIN EVENT TRANSITIONING TO THE CONVECTIVE
MODE BY WEDNESDAY NIGHT. AT THIS TIME...THE FORECAST DOES NOT
REFLECT SEVERE WEATHER POTENTIAL DUE TO THE MODEL CONFLICT.
TEMPERATURES WEDNESDAY ARE PROBLEMATIC AT BEST AS WE COULD SEE MOST
OF THE AREA STUCK IN THE 50S WITH RAIN WEDNESDAY AND WEDNESDAY NIGHT
OR TEMPERATURES COULD REBOUND WELL INTO THE 60S OR LOWER 70S IF WE
GET INTO THE WARM SECTOR. AT PRESENT...THE FORECAST GOES FOR UPPER
50S INLAND TO MID 60S COASTAL AREAS WEDNESDAY WITH MINS WEDNESDAY
NIGHT WITHIN ABOUT 5 DEGREES OF WEDNESDAYS HIGHS.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 300 AM MONDAY...AFTER SOME RESIDUAL CLOUDS AND PERHAPS A FEW
SHOWERS THE FIRST HALF OF THURSDAY...A COLD FRONT WILL SWEEP THROUGH
THE AREA AND HIGH PRESSURE WILL BUILD INTO THE AREA IN ITS WAKE.
THE RESULT WILL BE FAIR BUT COOL WEATHER THROUGH SUNDAY.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AS OF 18Z TERMINALS ARE VFR WITH SCATTERED MID AND HIGH LEVEL CLOUDS
AT THE COASTAL TERMINALS AND MID-LEVEL CEILINGS DEVELOPING AT
FLO/LBT. A DISSIPATING AREA OF RAIN CONTINUES TO MOVE EAST
TOWARDS THE TERMINALS AHEAD OF AN ADVANCING COLD FRONT. EXPECT THE
RAIN TO HOLD TOGETHER ENOUGH TO AFFECT THE FLO/LBT TERMINALS
AROUND 22Z AND CONTINUE TO AFFECT THE TERMINALS FOR SEVERAL HOURS
WITH TEMPO SHOWERS/MVFR VISIBILITIES. THE AREA OF RAIN WILL
CONTINUE ADVANCING EAST...AFFECTING THE COASTAL TERMINALS BY
01-02Z.
THE COLD FRONT WILL MOVE THROUGH THE FLO/LBT TERMINALS 01Z-03Z AND
THE COASTAL TERMINALS 03Z-05Z WITH WINDS SHIFTING TO THE NORTHWEST
AROUND 10 KNOTS...WITH A FEW GUSTS TO 20 KNOTS POSSIBLE FOR SEVERAL
HOURS AFTER FROPA. COULD BE A BRIEF PERIOD OF POST FRONTAL MVFR
CEILINGS BUT CHANCES ARE LOW ATTM THUS WILL NOT INCLUDE IN TAFS.
SKIES WILL BECOME CLEAR AFTER MIDNIGHT WITH WINDS VEERING TO THE
NORTH AND DECREASING TO LESS THAN 10 KNOTS IN THE PRE-DAWN HOURS.
COULD BE SOME LIGHT FOG DEVELOP IN THE PRE-DAWN HOURS WITH MOIST
SOILS...CLEAR SKIES AND COOL AIR ADVECTION...BUT THINK WIND SPEEDS
WILL CONTINUE TO PROVIDE SUFFICIENT MIXING TO INHIBIT FOG FORMATION.
VFR/CLEAR SKIES EXPECTED TUESDAY MORNING WITH NORTHEAST WINDS AROUND
8 KNOTS.
EXTENDED OUTLOOK...IFR CONDITIONS/ISOLATED THUNDERSTORMS POSSIBLE
WEDNESDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 945 AM MONDAY...SMALL CRAFT ADVISORY REMAINS POSTED FOR THE
WATERS THIS EVENING AND OVERNIGHT...AS GUSTY 25 KT WINDS SET UP
AHEAD AND BEHIND FRONTAL PASSAGE. IT APPEARS MORE LIKELY THAT 25
KNOT WINDS WILL VERIFY BETTER THAN 6 FOOT SEAS...BUT A PRETTY GOOD
BET THAT 6 FOOT SEAS WILL BE FOUND BETWEEN 15-20NM OUT OVERNIGHT.
2 TO 4 FOOT SEAS MUCH OF TODAY WITH FRYING PAN AND OUTER SEAS
APPROACHING 5 FEET LATER THIS AFTERNOON. DOMINANT WAVE PERIODS WILL
RUN AROUND BETWEEN 4-6 SECONDS AS SW CHOP HOLDS MOST OF THE WAVE
ENERGY THROUGH TONIGHT. WEAK SE SWELL WAS EVENT IN SPECTRAL PLOTS
THIS MORNING...BUT THIS ONLY AROUND A FOOT THROUGH THE NEAR TERM.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 300 AM MONDAY...TUESDAY WILL BEGIN WITH N TO NW WINDS AT OR
JUST BELOW SCA CRITERIA. WINDS WILL DIMINISH TUESDAY AND TUESDAY
NIGHT AS THEY BECOME N TO NE AT 15 KT OR LESS BY EVENING. SEAS WILL
FALL TO 2 TO 3 FEET BY TUESDAY NIGHT. THE IMPROVED CONDITIONS WILL
BE SHORT LIVED THOUGH AS WINDS VEER THROUGH EAST TO S TO SW
WEDNESDAY AND WEDNESDAY NIGHT. SPEEDS WILL RAMP UP TO 25 TO 30 KT
AND SEAS COULD BUILD AS HIGH AS 8 TO 10 FEET AT 20 NM.
LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 300 AM MONDAY...WINDS WILL SHIFT TO THE W THURSDAY MORNING
THEN NW THURSDAY AFTERNOON AND DECREASE TO AROUND 15 KT. WINDS WILL
TURN MORE NORTHERLY BY FRIDAY AT 10 TO 15 KT. SEAS WILL SUBSIDE
THROUGH THE PERIOD...REACHING 2 TO 3 FEET BY FRIDAY.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST
TUESDAY FOR AMZ250-252-254-256.
&&
$$
NEAR TERM....COLBY
SHORT TERM...RICKN
LONG TERM....RICKN
AVIATION.....MRMR
