-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KILM 050955
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
455 AM EST THU DEC 5 2013

.SYNOPSIS...
DENSE FOG WILL CONTINUE AS AN UNSEASONABLY WARM AND HUMID AIR MASS
CONTINUES TO OVERSPREAD THE AREA THROUGH TODAY. ABOVE NORMAL
TEMPERATURES WILL CONTINUE THROUGH EARLY SATURDAY. A COLD FRONT
WILL MOVE IN FROM THE NORTH ON SATURDAY BRINGING COOLER AIR AND
OCCASIONAL RAIN THROUGH THE LATTER HALF OF THE WEEKEND. A STRONGER
COLD FRONT WILL MOVE THROUGH ON TUESDAY SCOURING OUT ANY CLOUDS
AND UNSETTLED WEATHER AND USHERING IN MUCH COOLER AND DRIER AIR
THROUGH MID WEEK NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 345 AM THURSDAY...DENSE FOG ADV REMAINS IN EFFECT THROUGH 900
AM EDT THIS MORNING FOR THE ENTIRE ILM CWA INCLUDING THE ADJACENT
COASTAL WATERS OUT TO 20 NM.

UPPER RIDGING EXTENDING FROM THE GULF OF MEXICO...TO CONTINUE ACROSS
THE REGION DURING THIS NEAR TERM PERIOD. THE UPPER RIDGE AXIS WILL
SLIDE OFF THE EAST COAST TODAY THRU TONIGHT. SW FLOW ALOFT WILL
RESULT WITH SOME MOISTURE TAPPING OF THE GULF OF MEXICO. WITH A BUSY
SUBTROPICAL JET...TRAJECTORIES INDICATE PACIFIC MOISTURE ACTUALLY
GETS TAPPED. AT THE SFC...HIGH PRESSURE TO SLIDE OFF THE EAST COAST
WITH ITS RIDGE AXIS EXTENDING BACK ACROSS THE SE U.S. THE
COLD/ARCTIC FRONT DROPPING SE WILL SLOW ITS FORWARD PROGRESSION
AS IT BECOMES ORIENTED PARALLEL TO THE FLOW ALOFT. BY FRI MORNING...
THE FRONT WILL BE CROSSING THE APPALACHIAN MOUNTAINS ACROSS THE
WESTERN CAROLINAS.

WEAK MID-LEVEL IMPULSE MOVING NE ACROSS THE WESTERN CAROLINAS THIS
AFTERNOON COULD PRODUCE A CHANCE FOR SHRA...MAINLY ACROSS THE
WESTERN PORTIONS OF THE ILM CWA. OTHERWISE...SKIES ACROSS THE FA
WILL CONSIST OF UPPER LEVEL MOISTURE...AND LIKELY DIURNALLY INDUCED
CU AS MAX TEMPS PUSH WELL INTO THE 70S AWAY FROM THE IMMEDIATE
COAST. RECORD HIGHS TODAY ARE AROUND 80 DEGREES...DEFINITELY IN
STRIKING DISTANCE. FOR TONIGHT...LOOK FOR ANOTHER ROUND OF FOG
ALTHOUGH WITH ADDITIONAL CLOUDINESS ALOFT COMPARED TO THIS
MORNING...IT MAY NOT BE AS THICK OR EXTENSIVE LIKE THIS THU AM.
ALONG THE IMMEDIATE COAST...SEA FOG WILL OCCASIONALLY PUSH ONSHORE
THROUGHOUT THE NEAR TERM PERIOD.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY 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 /SUNDAY 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 /10Z THURSDAY THROUGH MONDAY/...
AS OF 06Z...EXPECT WIDESPREAD AREAS OF DENSE FOG OVERNIGHT WITH
PREVAILING IFR/LIFR VSBYS...BECOMING VLIFR AT TIMES WITH VSBYS
DROPPING BELOW 1/4SM. LIFR CIGS 200-400 FT ARE ALSO LIKELY AS THE
FOG LAYER DEEPENS THROUGH THE PRE-DAWN THU HOURS. FOG/STRATUS
COULD PERSIST WELL AFTER SUNRISE...AND IT MAY TAKE MOST OF THE
MORNING FOR IFR CONDITIONS TO FINALLY IMPROVE TO MVFR/VFR. BY
MIDDAY...VFR SHOULD PREVAIL ACROSS THE CWA WITH S-SW WINDS AOB 10
KTS. FOG LOOKS TO BE AN ISSUE AGAIN AFTER 00Z FRIDAY AS DEWPOINTS
WILL SURGE ABOVE 60 DEGREES DURING THE DAY. ALSO...THE S-SW FLOW
WILL BE FAVORABLE FOR SEA FOG THAT COULD IMPACT KCRE IN THE
EVENING HOURS. HAVE INTRODUCED LIGHT BR IN THE TAFS ATTM SINCE FOG
CONFIDENCE IS LOW THIS FAR IN ADVANCE OF THE EVENT.

EXTENDED OUTLOOK...IFR FOG/STRATUS FRIDAY MORNING. RAIN AND MVFR/IFR
CONDITIONS POSSIBLE SATURDAY AND SUNDAY WITH A COLD FRONT. CHANCE OF
RAIN ON MONDAY.

&&

.MARINE...
-- Changed Discussion --
NEAR TERM /THROUGH TONIGHT/...
AS OF 400 AM THURSDAY...LOW STRATUS AND/OR SEA FOG WILL BE THE
PRIMARY WEATHER STORIES FOR THE LOCAL WATERS TODAY THROUGH TONIGHT.
EVEN WITH S-SW 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 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.
-- End Changed Discussion --

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...DENSE FOG ADVISORY UNTIL 9 AM EST THIS MORNING FOR SCZ017-023-
     024-032-033-039-053>056.

NC...DENSE FOG ADVISORY UNTIL 9 AM EST THIS MORNING FOR NCZ087-096-
     099-105>110.

MARINE...DENSE FOG ADVISORY UNTIL 9 AM EST THIS MORNING FOR AMZ250-252-
     254-256.

&&

$$
SYNOPSIS...RGZ
NEAR TERM...DCH
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...DCH/BJR