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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KILM 051703
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
1204 PM EST THU DEC 5 2013

.SYNOPSIS...
MILD AND HUMID CONDITIONS WILL CONTINUE THROUGH EARLY SATURDAY
AS AN UPPER RIDGE MOVES ACROSS THE AREA. A COLD FRONT WILL BRING
COOLER AIR WITH OCCASIONAL RAIN LATE SATURDAY THROUGH SUNDAY. A
STRONGER COLD FRONT WILL SWEEP THROUGH THE EASTERN CAROLINAS ON
TUESDAY...SCOURING OUT CLOUDS AND HUMIDITY WHILE USHERING IN COLDER
AND DRIER AIR INTO MID-WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 10 AM THURSDAY...THE DENSE FOG ADVISORY WAS ALLOWED TO END
AT 900 AM BUT WE EXTENDED THE ADVISORY OVER THE COASTAL WATERS
UNTIL MIDDAY...WHILE ADDRESSING COASTAL ZONE VISIBILITIES WITH AN
SPS AS BOUTS OF SEA FOG DRIFT ASHORE. THE DENSE FOG ADVISORY OVER
THE WATER COULD REQUIRE AN EXTENSION INTO THE AFTERNOON.

PLENTY CLOUDS ABOVE THE FOG CAN BE SEEN UPSTREAM AND PRECIPITABLE
WATERS ARE EXPECTED TO SURGE BRIEFLY LATE THIS AFTERNOON...AS A
SLUG OF GULF MOISTURE AND THE ASSOCIATED DISTURBANCE ALOFT OVER
GEORGIA THIS MORNING TRACKS NE OVER THE WESTERN HALF OF OUR
FORECAST ZONES. THE IDEA THEREFORE OF SCATTERED SHOWERS BETWEEN
4PM-8PM OVER OUR INTERIOR ZONES LOOKS ON TARGET. MID-LEVEL
MOISTURE ADVECTION WILL INCREASE IN THE AFTERNOON.

SEA FOG MAY IMPACT IMMEDIATE COASTAL ZONE LOCALS...ESPECIALLY S
AND SE FACING COASTLINES. THE MYRTLES STILL REMAIN ENTRENCHED IN
DENSE FOG THIS MID MORNING. THE SEA FOG MAY LINGER ALL DAY AND
COULD MAKE A MOVE INLAND MORE INTO AFTERNOON AS A SEA BREEZE
RESULTANT WIND CIRCULATION GEARS UP. AS A RESULT...LOCATIONS
THAT REMAIN TRAPPED IN THE MARINE LAYER WILL BE SIGNIFICANTLY
COOLER THAN AREAS FARTHER INLAND.

TEPID CONDITIONS OVERNIGHT...AS MILD AND MOIST AIR PREVAILS OVER
THE AREA. LOWS OVERNIGHT WILL SETTLE ONLY A FEW DEGREES BELOW THE
NORMAL HIGH FOR EARLY DECEMBER. AREAS OF DENSE FOG WILL AGAIN BE
FAVORED TONIGHT INTO DAYBREAK FRIDAY...AND ADVISORIES MAY BE
NEEDED.

&&

.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
AS OF 300 AM THURSDAY...FRIDAY WILL BE THE WARMEST DAY OF THE WEEK
AND THE FINAL DAY OF WELL ABOVE NORMAL TEMPS AS WARM AND MOIST
SOUTHERLY RETURN FLOW ON FRI GETS REPLACED BY COOL NORTHERLY WINDS
BEHIND FRONT THAT WILL MOVE SOUTH OF THE AREA ON SATURDAY. THE
RIDGE BECOMES MORE WELL DEFINED OFF THE SOUTHEAST COAST ON FRI
HOLDING OFF COLD FRONT WHICH MAKES VERY LITTLE PROGRESS INTO THE
CAROLINAS ON FRI. THE GRADIENT BETWEEN THE HIGH PRESSURE OFF
SHORE AND THE COLD FRONT APPROACHING WILL TIGHTEN PRODUCING AN
INCREASE IN SOUTHERLY WINDS ON FRIDAY. MOST OF THE MOISTURE
THROUGH THE COLUMN WILL BE CONFINED TO THE UPPER LEVELS ABOVE H3.
THEREFORE EXPECT SUN TO BE FILTERED OUT BY A DECENT AMOUNT OF
CIRRUS CLOUDS THROUGH FRI. TEMPS SHOULD SOAR WELL INTO THE 70S ON
FRIDAY WITH A VERY UNSEASONABLY WARM AND HUMID AIR MASS IN PLACE
AS H5 HEIGHTS RISE TO 586 DEM AND 850 TEMPS REACH 15 C. CLOUDS AND
CONTINUED WAA THROUGH FRI NIGHT WILL KEEP TEMPS ABOVE WHAT NORMAL
DAY TIME HIGH TEMPS WOULD BE FOR THIS TIME OF YEAR...CLOSER TO 60.
SHOULD CONTINUE TO SEE SOME SEA FOG ACROSS THE COASTAL WATERS
THROUGH THE FIRST HALF OF THE PERIOD AS VERY WARM AND HUMID AIR
ADVECTS OVER THE COOL SHELF WATERS.

MOISTURE THROUGH THE COLUMN WILL DEEPEN FRI NIGHT INTO SATURDAY AS
COLD FRONT BEGINS TO MAKE PROGRESS SOUTHEAST THROUGH THE
CAROLINAS AND TOWARD THE LOCAL AREA. EXPECT CLOUDS TO THICKEN WITH
INCREASING CHC OF PCP HEADING INTO SATURDAY AS COLD FRONT
APPROACHES. PCP WATER VALUES AROUND 1.5 INCHES ON FRI WILL JUMP
UP TO 1.8 INCHES ALONG AND AHEAD OF COLD FRONT AS IT TRACKS
THROUGH THE AREA ON SATURDAY. EXPECT MOST LIFT AND SUPPORT FOR PCP
TO BE LOCATED IN THE VICINITY OF THE COLD FRONT AS IT TRACKS SOUTH
THROUGH THE AREA THROUGH SATURDAY MORNING. THE FRONT SHOULD CLEAR
THE AREA BY EARLY AFTERNOON BUT THIS WILL NOT LEAD TO CLEARING AS
THE SHALLOW COOLER AND DRIER AIR ADVECTING IN FROM THE NORTH WILL
GET OVERRUN BY STIFF SOUTHWESTERLY FLOW ALOFT AS RIDGE REMAINS
ANCHORED OFF SHORE TO THE EAST. THIS WILL PRODUCE AN EXTENDED
PERIOD OF ISENTROPIC LIFT THROUGH LATE SAT INTO THE EARLY SUN WITH
A DECENT AMOUNT OF RAINFALL EXPECTED...UP AROUND A HALF INCH IN
PLACES INLAND. OVERALL EXPECT CLOUDS THROUGH THE PERIOD WITH
RAINFALL THROUGH SATURDAY AS TEMPS FALL THROUGH LATE DAY IN
SHALLOW CAA. EXPECT A 30 TO 40 DEGREE TEMPERATURE FALL FROM FRI
AFTERNOON TO SUN MORNING.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 300 AM THURSDAY...A COLD FRONT SHOULD BE DRAPED ACROSS
GEORGIA EARLY SUNDAY BEFORE RETURNING BACK NORTH AS A WARM FRONT
LATE SUNDAY INTO MONDAY. MODELS CONTINUE TO SHOW A CLASSIC WEDGE
PATTERN SET UP THROUGH SUNDAY WITH RIDGE OF COOL HIGH PRESSURE
INLAND AND COASTAL TROUGH/FRONT SETTING UP. THIS COLD FRONT WILL
BRING VERY SHALLOW COLD AIR AS THE WINDS ALOFT REMAIN STIFF OUT OF
THE SOUTHWEST. THE LOW LEVEL THICKNESSES DROP ABOUT 30 M WHILE THE
850 TEMPS DO NOT SHOW MUCH OF DROP AS THE COOL AIR REMAINS VERY
SHALLOW. THE MORE APPRECIABLE PCP SHOULD COME TO AN END EARLY
SUNDAY BUT EXPECT LOW CLOUDS AND LIGHTER PCP TO CONTINUE THROUGH
MUCH OF SUNDAY AS ISENTROPIC UPGLIDE CONTINUES. THIS WILL LEAD TO
A DECREASE IN POPS AS THE CHC OF MEASURABLE PCP WILL DIMINISH
THROUGH SUNDAY BUT INTERMITTENT RAIN/DRIZZLE SHOULD CONTINUE UNTIL
WEDGE BREAKS AND COASTAL TROUGH/FRONT PUSHES INLAND AND NORTH
THROUGH THE AREA.

TOUGH TO SAY WHEN THE WEDGE WILL BREAK BUT IT LOOKS LIKE IT SHOULD
BY MONDAY AS NEXT SYSTEM HEADS TOWARD THE CAROLINAS FROM THE
NORTHWEST. THIS WILL LEAD TO AN INCREASE IN WARM AND MOIST AIR
ONCE AGAIN AS SURFACE WINDS INCREASE OUT THE SOUTHWEST AHEAD OF
APPROACHING COLD FRONT. MOISTURE WILL DEEPEN THROUGH THE COLUMN
WITH PCP WATER VALUES REACHING AROUND 1.7 INCHES BY EARLY TUESDAY
AS COLD FRONT PROGRESSES THROUGH THE CAROLINAS. A VERY BROAD MID
TO UPPER TROUGH SHOULD PUSH THE FRONT THROUGH SLOWLY ON TUES. THE
BEST DYNAMICS WITH THIS SYSTEM LOOK LIKE THEY WILL REMAIN TO THE
NORTHWEST OF FORECAST AREA ON TUES...BUT EXPECT SHOWERS ALONG AND
AHEAD OF FRONT.

EXPECT CLEARING TUES NIGHT INTO WED WITH COOLER AND DRIER AIR
MOVING IN FOR MID WEEK AS HIGH PRESSURE BUILDS INTO THE AREA.
TEMPS REACHING UP INTO THE 70S ON MONDAY IN WAA WILL DROP BACK
DOWN BELOW NORMAL BY WED IN CAA BEHIND FRONT.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
-- Changed Discussion --
AS OF 18Z...A SPRINKLE IS POSSIBLE THIS AFTERNOON AT THE INLAND
TERMINALS WITH A WEAK STRIP OF MID LEVEL MOISTURE...HOWEVER ANY
PRECIP WILL LIKELY NOT AFFECT AVIATION CONDITIONS MUCH.

LOOKS LIKE A GOOD SETUP FOR SEA FOG/STRATUS THIS EVENING WITH
DEWPOINTS RUNNING 7-8 DEGREES ABOVE OCEAN TEMPS. FORECAST SOUNDINGS
ALSO DEPICT SATURATION BELOW 500 FT AN HOUR OR TWO AFTER SUNSET.
LIKEWISE SOUTH SOUTHWEST TRAJECTORY IS IDEAL. MAY BE A BIT SLOW OF
THE ONSET OF THE FOG...BUT AM STILL AHEAD OF SOME OF THE MODELS.
LOOK FOR LIFR CONDITIONS THROUGH THE OVERNIGHT HOURS. LIFR
CONDITIONS WILL IMPROVE AFTER 14Z AS SOLAR INSOLATION MIXES THINGS
OUT. CONTINUED SOUTHWEST FLOW.

EXTENDED OUTLOOK...IFR FOG/STRATUS POSSIBLE SATURDAY MORNING. A
BACKDOOR COLD FRONT PUSHES SOUTH MIDDAY SATURDAY WITH DETERIORATING
CONDITIONS. MVFR/IFR CONDITIONS WITH PATCHY LIGHT RAIN EXPECTED
SATURDAY AFTERNOON THROUGH SUNDAY MORNING. SHOWERS POSSIBLE TUESDAY.
-- End Changed Discussion --
&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 10 AM THURSDAY...LOW STRATUS AND/OR SEA FOG WILL BE THE
PRIMARY WEATHER STORIES FOR THE LOCAL WATERS THROUGH TONIGHT. EVEN
WITH S-SW WINDS AT 5 TO 15 KT...THE SEA FOG...A TRUE ADVECTION
TYPE FOG...WILL CONTINUE TO PLAGUE THE ILM WATERS. WITH ATLANTIC
SSTS IN THE 50S AND 60+ DEGREE DEWPOINTS ADVECTING ACROSS THESE
COOLER WATERS...THE RESULT WILL BE AN EXTENDED ROUND OF SEA FOG
CONTINUING LIKELY FOR THE NEXT 24+ HRS IN VARYING DEGREES OF
INTENSITY.

WITH THE SFC RIDGE AXIS JUST SOUTH OF THE ILM WATERS...LOOK FOR
WINDS TO COME FROM THE S-SSW DIRECTION. THE SFC PG WILL BEGIN TO
TIGHTEN AS A RESULT OF THE APPROACHING COLD FRONT AND/OR THE
RETREATING ATLANTIC SFC HIGH. SPEEDS WILL RUN 5 TO 10 KT
TODAY...INCREASING 10 TO 15 BY EARLY THIS EVENING...AND POSSIBLY
UP TO 20 KT ACROSS THE WARMER SSTS ALONG OR JUST OUTSIDE OF 20 NM.
SIGNIFICANT SEAS WILL RUN 2 TO 3 FT...AND BUILD UP TO 4 FT
TONIGHT. WIND DRIVEN WAVES EXHIBITING 3 TO 6 SECOND PERIODS...WILL
BECOME THE DOMINANT CONTRIBUTOR TO THE SIGNIFICANT SEAS.

SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 300 AM THURSDAY...UNSEASONABLE WARM AND MOIST AIR MASS WILL
LINGER ACROSS THE WATERS THROUGH FRIDAY INTO SATURDAY UNTIL A COLD
FRONT TRACKS SOUTH THROUGH THE WATERS SAT AFTN. THIS WILL PRODUCE
POTENTIAL FOR SEA FOG THROUGH MUCH OF THE PERIOD...BUT WINDS WILL
INCREASE OUT OF THE SW UP TO 15 TO 20 KTS THROUGH LATE FRI INTO
SATURDAY AHEAD OF APPROACHING COLD FRONT. THIS INCREASING
SOUTHERLY PUSH WILL DRIVE SEAS UP TO 3 TO 5 FT THROUGH FRI INTO
EARLY SATURDAY.

WINDS WILL SHIFT AROUND FROM SW TO N-NE ON SATURDAY BEHIND COLD
FRONT AS IT PROGRESSES FURTHER SOUTH THROUGH SAT NIGHT. THE OFF
SHORE FLOW INITIALLY WILL HELP TO LOWER SEAS BUT BY SAT NIGHT THE
FLOW SHOULD INCREASE OUT OF THE NE IN MORE OF A PINCHED GRADIENT AS
COASTAL TROUGH DEVELOPS WITH SEAS REACHING BACK UP TO 5 FT IN
OUTER WATERS.

LONG TERM /SUNDAY THROUGH MONDAY/...
AS OF 300 AM THURSDAY...NORTHEASTERLY FLOW WILL CONTINUE THROUGH
EARLY SUNDAY IN PINCHED GRADIENT BETWEEN WEDGE OF HIGH PRESSURE
INLAND AND COASTAL TROUGH/WARM FRONT OVER OR JUST SOUTHEAST OF
LOCAL WATERS. WINDS SHOULD DIMINISH BUT REMAIN NE MOST OF SUNDAY
BUT AT SOME POINT WILL TRANSITION TO THE SOUTH AGAIN AS COASTAL
TROUGH/WARM FRONT PUSHES NORTH THROUGH THE WATERS. FOR NOW WILL
TRANSITION TO SOUTHERLY RIGHT AROUND MIDNIGHT SUNDAY NIGHT. SEAS
WILL DROP TO 2 TO 4 FT THROUGH SUNDAY.

EXPECT INCREASING S-SW FLOW THROUGH MONDAY INTO MON NIGHT AS NEXT
COLD FRONT MAKES ITS WAY INTO THE CAROLINAS. SW WINDS UP TO 20 KTS
WILL PUSH SEAS UP TO 4 TO 6 FT MONDAY.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...COASTAL FLOOD ADVISORY UNTIL NOON EST TODAY FOR NCZ107.

MARINE...DENSE FOG ADVISORY UNTIL NOON EST TODAY FOR AMZ250-252-254-256.

&&

$$

NEAR TERM...COLBY
SHORT TERM...RACHEL
LONG TERM...ZOUZIAS-GROSS
AVIATION...DL