-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KILM 061114
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
615 AM EST FRI DEC 6 2013

.SYNOPSIS...
UNSEASONABLY MILD AND HUMID CONDITIONS WILL PERSIST THROUGH EARLY
SATURDAY AS HIGH PRESSURE SITS OFFSHORE. A COLD FRONT WILL BRING
COOLER AIR WITH PERIODS OF LIGHT RAIN LATE SATURDAY THROUGH
SUNDAY. A BRIEF WARM UP WILL OCCUR MONDAY...BEFORE A STRONGER COLD
FRONT CROSSES THE EASTERN CAROLINAS ON TUESDAY. COLDER AND DRIER
AIR WILL MOVE IN MID-WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 345 AM FRIDAY...MODELS CONTINUE TO HOLD THE UPPER RIDGING
CENTERED OVER THE EASTERN 2/3RDS OF THE GULF OF MEXICO IN PLACE
DURING THE NEAR TERM. THE UPPER RIDGE AXIS EXTENDING NE WILL REMAIN
RELATIVELY STATIONARY...AND WELL EAST OF THE FA. THIS WILL RESULT IN
SW FLOW ALOFT THROUGHOUT THE NEAR TERM PERIOD...WHICH WILL KEEP THE
PROGRESSION OF THE COLD FRONT TOWARD THE SOUTHEAST U.S. AT A
RELATIVELY SLOW PROGRESSION. FOR EXAMPLE...THIS MORNING THE COLD
FRONT WILL EXTEND NE-SW ACROSS THE SPINE OF THE APPALACHIANS OVER
THE WESTERN CAROLINAS. COME 24 HRS LATER ON SATURDAY MORNING...THE
COLD FRONT IS PROGGED TO EXTEND NE-SW ACROSS THE EASTERN CAROLINAS.
THE FORCING AHEAD OF THE COLD FRONT IS RATHER MINIMAL WITH NO MID
LEVEL VORTS OR S/W TROFS ALOFT TO PROVIDE ADDITIONAL LIFTING. AS A
RESULT...POPS FOR SHRA WILL REMAIN ISOLATED AT BEST FOR DAYLIGHT
HRS...AND INCREASE MAINLY AFTER MIDNIGHT TONIGHT AS THE COLD FRONT
REACHES THE WESTERN PORTIONS OF THE ILM CWA. MOST OF THE PCPN ACROSS
THE FA FROM THIS COLD FRONT WILL OCCUR POST FRONTAL...WHICH IS EARLY
ON IN THE SHORT TERM PERIOD. DID NOT INCLUDE THUNDER BUT INDICATED
CONVECTIVE FEATURES THAT COULD PRODUCE EMBEDDED MODERATE RW WITHIN
THE AREA OF R- TOWARDS DAYBREAK SAT.

MODELS A LITTLE BEHIND WITH CURRENT SFC TEMPS AND DEWPOINTS ACROSS
THE FA AND AS A RESULT HAVE GONE WITH THE HIGHER GFS MOS GUIDANCE
FOR MAX/MIN TEMPS...ESPECIALLY ALONG THE IMMEDIATE COAST.
HOWEVER...THE COAST MAY BE SUBJECT TO OCCASIONAL ONSHORE MOVEMENT OF
SEA FOG WHICH COULD KEEP MAX TEMPS MUCH LOWER. AT THIS TIME...
SOMEWHAT DIFFICULT TO IDENTIFY THIS FOG ACROSS THE LOCAL WATERS WITH
THE LATEST SAT IMAGERY DUE TO MID AND UPPER LEVEL CLOUDS
PRESENT.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 300 AM FRIDAY...COLD FRONT WILL BRING CHANGE OF AIR MASS
THROUGH THE WEEKEND ALONG WITH QUITE A BIT OF RAIN. A COLD
FRONT WILL DROP DOWN FROM THE NORTH THROUGH SAT MORNING. THE HIGH
TEMP WILL NOT DIFFER MUCH FROM THE OVERNIGHT LOW TEMP FROM THE
NIGHT BEFORE AS COOLER AIR BEGINS TO FUNNEL IN BY NOON ON
SATURDAY. THIS SHALLOW BOUNDARY WILL BRING SURFACE TEMPS DOWN BUT
WINDS ALOFT WILL REMAIN OUT OF THE W-SW AS MID TO UPPER RIDGE
REMAINS ANCHORED OFF SHORE. OVERALL EXPECT LIFT ASSOCIATED MORE IN
LINE WITH FRONT AND THEN DECENT ISENTROPIC LIFT DEVELOPING THROUGH
LATE SATURDAY INTO SUNDAY TO PRODUCE PLENTY OF LOW CLOUDS AND
PERIODS OF RAIN THROUGH MUCH OF THE WEEKEND. INITIALLY THE
WESTERLY COMPONENT TO THE FLOW MAY INHIBIT BEST CHC OF RAIN BUT
EXPECT STEADIER RAIN TO DEVELOP THROUGH LATE SATURDAY INTO SAT
NIGHT AND MAY END UP WITH RAINFALL TOTALS UPWARDS OF A HALF INCH
IN SPOTS. THE PCP WATER VALUES WILL FALL AS COLD FRONT MAKES ITS
WAY OFF SHORE AN WE TRANSITIONS FROM A WARM HUMID AIR MASS TO
COOLER AIR MASS WITH WEDGE SETTING UP. BY SUNDAY THE COLD FRONT
WILL SHIFT BACK NORTH AND A COASTAL TROUGH/WARM FRONT WILL
EVENTUALLY MAKE ITS WAY INLAND AND NORTH BY SUNDAY NIGHT INTO
MONDAY.

COOL NE FLOW...CLOUDS AND AND RAIN WILL KEEP TEMPS IN THE 60S ON
SATURDAY AND SHALLOW CAA WILL CONTINUE INTO SUN MORNING BRINGING
OVERNIGHT LOWS CLOSER TO 40 BY EARLY SUNDAY...ABOUT A 20 DEGREE
DROP FROM THE TEMPS 24 HOURS BEFORE. TEMPS WILL HAVE TROUBLE
RECOVERING SUN AFTN AS TYPICAL WEDGE OF COOL HIGH PRESSURE SETS
UP WITH LOW CLOUDS AND RAIN CONTINUING AND EXPECT TEMPS ON SUNDAY
TO REMAIN CLOSER TO 50 OR BELOW IN MANY SPOTS INLAND.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 300 AM FRIDAY...A CLASSIC WEDGE PATTERN WILL BREAK ON MONDAY
AS COASTAL TROUGH/WARM FRONT SHIFTS NORTH AND NEXT COLD FRONT
APPROACHES THE CAROLINAS. ONCE WARM FRONT SHIFTS NORTH...A DEEP
SOUTHERLY FLOW WILL SET UP ONCE AGAIN. TEMPS WILL BE ABLE TO
RECOVER IN WARM AND MOIST AIR STREAMING INTO AREA FROM THE SOUTH
THROUGH MONDAY. TEMPS WILL REACH UP NEAR 70 AND DEWPOINT TEMPS
WILL INCREASE INTO THE 60S AGAIN. THIS MAY LEAD TO SOME SEA FOG
MON MORNING.

MOISTURE WILL DEEPEN THROUGH THE COLUMN MON INTO MON NIGHT 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 BY TUES AFTN. THE BEST
DYNAMICS WITH THIS SYSTEM LOOK LIKE THEY WILL REMAIN TO THE
NORTHWEST OF FORECAST AREA ON TUES...BUT EXPECT ENOUGH LIFT
ASSOCIATED WITH FRONT TO PRODUCE SHOWERS ALONG AND AHEAD OF FRONT.

EXPECT CLEARING TUES NIGHT INTO WED WITH DEEP COOL AND DRY 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 STRONG CAA BEHIND FRONT. DEEP COOL AND
DRY AIR WILL SCOUR OUT THE AREA WITH CLEAR AND COOL WEATHER
EXPECTED FOR MID WEEK. MAX TEMPS ON WED WILL ONLY REACH THE 50S
ACROSS MUCH OF THE AREA. MORE IDEAL RADIATIONAL COOLING WED NIGHT
WILL LEAD TO TEMPS DROPPING BELOW FREEZING IN MANY PLACES AND
ONLY RECOVERING CLOSE TO 50 ON THURS IN FULL DECEMBER SUNSHINE.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
-- Changed Discussion --
AS OF 12Z...ONLY PLACE AFFECTED BY SEA STRATUS IS CRE WITH A 300 FT
CEILING. APPEARS MYR WILL BE SPARED DUE TO THE TRAJECTORY...BUT A
BRIEF CEILING IS POSSIBLE...LIKEWISE FOR ILM. THE INLAND TERMINALS
WILL LIKELY REMAIN VFR...MAINLY DUE TO STRONG WINDS AT THE BOUNDARY
LAYER. HIGH PRESSURE WILL SLOWLY RECEDE OVER THE NEXT 24
HOURS...GIVING WAY TO A SLOW MOVING COLD FRONT THAT WILL DROP IN ON
SATURDAY. SOME SEA FOG IS POSSIBLE AGAIN TONIGHT WITH CONTINUED HIGH
DEWPOINTS. SOUTHWEST FLOW WILL CONTINUE...GUSTY A TIMES TODAY.

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

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 345 AM FRIDAY...THE COLD NEARSHORE WATERS EXHIBITING 50S
SSTS HAS CONTINUED TO KEEP THE WINDS ALOFT FROM MIXING THRU THE
STABLE MARINE LAYER TO THE OCEAN SFC. AS A RESULT...A RATHER BIG
DISPARITY IN WIND SPEEDS WILL EXIST ACROSS THE ILM WATERS...IE.
LATEST OBS AT MYRTLE BEACH SPRINGMAID PIER INDICATED S AT 7 WITH SST
OF 55 DEGREES. BUOY 41013...FRYING PAN SHOALS BUOY...INDICATED SW AT
16 WITH A SST OF 74 DEGREES.

THE SFC PG ACROSS THE AREA WATERS WILL SLOWLY TIGHTEN AS THE COLD
FRONT APPROACHES FROM THE NW THROUGH TONIGHT. OVERALL...WIND SPEEDS
WILL INCREASE TO THE 10 TO 20 KT RANGE BY TONIGHT...WITH SOME WIND
GUSTS UP TO 25 KT MAINLY ACROSS THE WARMER WATERS JUST OUTSIDE OF
THE ILM AREA OF RESPONSIBILITY. SIGNIFICANT SEAS WILL BUILD FROM 2
TO 3 FT EARLY THIS MORNING TO 3 TO 5 FT BY THIS EVENING AND TONIGHT.
THE WINDS AND SEAS COMBINED FOR LATER TONIGHT SHOULD BREACH SCEC
CRITERIA.

SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 300 AM FRIDAY...SW WINDS AHEAD OF AN APPROACHING COLD
FRONT ON SATURDAY WILL KEEP SEAS UP AROUND 3 TO 5 FT. THIS COLD
FRONT WILL MOVE SOUTH THROUGH THE WATERS SAT AFTN...WITH A RAPID WIND
SHIFT TO THE NE. WINDS CLOSER TO 15 KTS EARLY SATURDAY WILL
DIMINISH AS THE FRONT MOVES THROUGH BUT WILL INCREASE TO 15-20
KTS...ISOLATED HIGHER...FROM THE NE SATURDAY NIGHT BEHIND THE COLD
FRONT. SEAS WILL DROP SLIGHTLY THROUGH SATURDAY BEFORE INCREASING
IN STIFF NORTHEAST WIND BEHIND COLD FRONT. THIS WILL INCREASE SEAS
UP TOWARD 5 TO 6 FT IN THE OUTER WATERS. LATEST WNA SHOWS A SPIKE
IN SEAS ABOVE SCA THRESHOLDS FOR A BRIEF PERIOD EARLY SUNDAY
MORNING. A PINCHED GRADIENT MAY EXIST FOR A WHILE ON SUNDAY AS
COLD AIR REMAINS WEDGED INLAND AND LINGERING FRONT/COASTAL TROUGH PROGRESSES
NORTH. THIS WARM FRONT SHOULD MOVE INTO THE WATERS BY EARLY MONDAY
WITH WINDS BEGINNING TO SHIFT AROUND TO THE SOUTH. SEAS WILL DROP
THROUGH LATE SUNDAY AS WINDS DIMINISH AND SHIFT AROUND.

LONG TERM /MONDAY THROUGH TUESDAY/...
AS OF 300 AM FRIDAY...LIGHT SOUTHEAST FLOW WILL BE IN PLACE ON
MONDAY BUT WILL CONTINUE TO VEER TO SOUTHWEST THROUGH MONDAY
INCREASING ONCE AGAIN TO 15-20 KNOTS AS A COLD FRONT APPROACHES
FROM THE NORTHWEST. THIS COLD FRONT WILL MOVE ACROSS THE WATERS
BY TUES AFTN WITH WINDS SWITCHING TO NORTHWEST AT 15-20 KNOTS.
SEAS WILL INCREASE TO 3-5 AND POSSIBLY 6 TO 7 FT LATE MONDAY AND
EARLY TUESDAY IN STRONG SOUTHERLY PUSH. THE OFF SHORE FLOW BEHIND
THE FRONT WILL ALLOW SEAS TO DROP TO 2 TO 4 FT BY WED
MORNING...ESPECIALLY IN THE NEAR SHORE WATERS. WITH SEAS AROUND 5
FT CONFINED TO MAINLY THE OUTER WATERS.

&&

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

&&

$$

NEAR TERM...DCH
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...DL