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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
317 AM EST SUN DEC 21 2014

.SYNOPSIS...
A WEDGE OF HIGH PRESSURE WILL KEEP CLOUDS AND VERY LOW RAIN CHANCES 
IN THE FORECAST TODAY. RAIN CHANCES INCREASE SLIGHTLY MONDAY AS LOW 
PRESSURE MOVES ALONG THE COAST BUT STAYS WELL OFFSHORE. THE WEATHER 
WILL REMAIN UNSETTLED TUESDAY BUT GROW A BIT MORE SEASONABLE. A 
STRONG COLD FRONT WILL BRING SHOWERS AND MAYBE THUNDERSTORMS 
WEDNESDAY INTO WEDNESDAY NIGHT. SUNSHINE FINALLY RETURNS ON 
CHRISTMAS DAY WHILE IT TURNS COOLER. DRY AND FAIRLY SUNNY WEATHER 
SHOULD LAST INTO THE WEEKEND. 

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 3:30 AM SUNDAY...NORTHEAST WINDS WILL CONTINUE THROUGH THE 
NEAR TERM...INCREASING FROM PRESENT 10 TO 15 KT RANGE TO 15 TO 20 
KTS LATER THIS MORNING AS A FRONTAL SYSTEM WAVERS BACK TOWARDS THE 
COAST. SEAS WILL BUILD INTO THE 3 TO 5 FT RANGE...WHICH HAS PROMPTED 
THE POSTING OF EXERCISE CAUTION HEADLINES. CONDITIONS WILL GRADUALLY 
IMPROVE OVERNIGHT AS THE GRADIENT WEAKENS.



&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 3 AM SUNDAY...CLOUDS HANG TOUGH MONDAY TO KEEP TEMPS BELOW 
CLIMATOLOGY ONCE AGAIN AS SURFACE WEDGE OF HIGH PRESSURE RIDGES IN 
FROM POINTS NORTH. FRONTAL BOUNDARY STALLED WELL OFFSHORE AND IT 
WILL HAVE A WAVE OF LOW PRESSURE RIDGE UP ALONG OUR LATITUDE LATE IN 
THE DAY. AS THIS OCCURS SOME AREAS MAY EXPERIENCE SOME WEAK 
ISENTROPIC UPGLIDE THAT LEADS TO SOME LIGHT RAIN. WITH THIS FORCING 
VERY WEAK AND MOISTURE CONFINED TO RELATIVELY LOW LEVELS 
NON-MEASURABLE SPRINKLES SEEM JUST AS LIKELY AS MEASURABLE RAINFALL 
ESPECIALLY INLAND. THE WEDGE STARTS TO BREAK DOWN ON TUESDAY AND THE 
UPPER PATTERN WILL REALLY BE AMPLIFYING. THIS WILL CERTAINLY LEAD TO 
A MILDER AFTERNOON BUT THE INCREASED MOISTURE ADVECTION WILL KEEP 
THE SKY CLOUDY. RAIN CHANCES WILL ALSO INCREASE FAIRLY 
RAPIDLY...MORESO FROM MOISTURE ADVECTION RATHER THAN FORCING LEADING 
TO ASCENT. IN FACT IN SUCH A SITUATION MODELS ARE OFTEN A BIT FAST 
ON ADVECTING MEASURABLE RAINFALL AND SO THERE MAY BE A FEW 
RAIN-FREE HOURS EARLY TUESDAY. 

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 3 AM SUNDAY...WEDNESDAY PROBABLY REPRESENTS THE BEST RAIN 
CHANCES THAT THE AREA HAS SEEN AND POSSIBLY WILL SEE FOR QUITE SOME 
TIME. HIGHLY AMPLIFIED PATTERN TO DRIVE A COLD FRONT THROUGH BY 
WEDNESDAY NIGHT. THE AMPLITUDE OF THE SYSTEM WILL BE SUCH THAT IT 
WILL SCOOP UP PLENTY OF GULF MOISTURE. IN THE WAKE OF THIS SYSTEM 
CHRISTMAS IS SHAPING UP TO BE RATHER BRISK AND COOLER BUT WILL AT 
LEAST FEATURE A RETURN OF SUNSHINE WHICH BY THEN WILL HAVE BEEN 
ABSENT FOR SEVERAL DAYS. THIS COOL HIGH THEN WEAKENS AND MOVES INTO 
THE REGION BY FRIDAY WHICH SHOULD SHUT OFF THE COOL ADVECTION. 
SATURDAY MAY BE EITHER SEASONABLE OR A FEW DEGREES WARMER AS ANOTHER 
COLD FRONT APPROACHES FROM THE NW. 

&&

.AVIATION /06Z SUNDAY THROUGH THURSDAY/... 
AS OF 06Z...EXPECT CIGS TO FLUCTUATE BETWEEN MVFR/VFR OVERNIGHT
WITH BRIEF PERIODS OF TEMPO IFR POSSIBLE EARLY THIS MORNING. THE
3-6KFT LAYER REMAINS SATURATED THROUGH THE PERIOD...SO STRATOCU
WILL PERSIST AS A COASTAL TROUGH SHARPENS OFFSHORE. ALTHOUGH THERE
ARE A FEW PATCHES OF 800-1000 FT STRATUS OUT THERE TONIGHT...DO
NOT ANTICIPATE PERSISTENT CIGS AT THESE LEVELS BASED ON THE
FORECAST SOUNDINGS AND SREF PROBS. CIGS MAY BRIEFLY IMPROVE TO VFR
IN THE MORNING BEFORE ANOTHER ROUND OF MOIST ISENTROPIC LIFT
BRINGS MORE -RA AND LOWERS THEM BACK DOWN TO MVFR AGAIN. PRECIP
SHOULD BEGIN AROUND 15Z AT THE SOUTHERN TERMINALS AND AFTER 18Z AT
KILM/KLBT. NORTHEAST WINDS AOB 10 KT WILL PERSIST THROUGH THE DAY.
AFTER 00Z MON...CIGS WILL DROP FURTHER AS RAIN CONTINUES TO FALL.
WOULD NOT BE SURPRISED TO SEE IFR CIGS BY THE END OF THE PERIOD
ESPECIALLY ALONG THE COAST...BUT FOR NOW WILL KEEP ALL SITES MVFR.

EXTENDED OUTLOOK...RAIN LIKELY MON WITH MVFR/IFR CIGS AS A COASTAL
TROUGH DEVELOPS OFFSHORE. SHOWERS/TEMPO MVFR EXPECTED TUE/WED
AHEAD OF A STRONG COLD FRONT. GUSTY WINDS WED/THU BEFORE AND AFTER
FROPA. THU WILL BE VFR AT ALL TERMINALS.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 3:30 AM SUNDAY...NORTHEAST WINDS WILL CONTINUE THROUGH THE 
NEAR TERM...INCREASING FROM PRESENT 10 TO 15 KT RANGE TO 15 TO 20 
KTS LATER THIS MORNING AS A FRONTAL SYSTEM WAVERS BACK TOWARDS THE 
COAST. SEAS WILL BUILD INTO THE 3 TO 5 FT RANGE...WHICH HAS PROMPTED 
THE POSTING OF EXERCISE CAUTION HEADLINES. CONDITIONS WILL GRADUALLY 
IMPROVE OVERNIGHT AS THE GRADIENT WEAKENS.

SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 3 AM SUNDAY...NE WINDS ON MONDAY WILL VEER SLIGHTLY ON TUESDAY 
AS A WEDGE OF HIGH PRESSURE OVER LAND WEAKENS. MONDAY WILL ALSO 
BRING ABOUT 5KT OF HIGHER WIND SPEED AT TIMES AS LOW PRESSURE MOVES 
UP ALONG A FRONTAL BOUNDARY OFF THE COAST. TUESDAY NIGHT THE FLOW 
WILL VEER AGAIN MORE DECIDEDLY AS THE APPROACH OF A COLD FRONT AND 
DYNAMIC UPPER SYSTEM APPROACH. WINDS WILL ALSO INCREASE LATE TUESDAY 
NIGHT ABOVE THE BOUNDARY LAYER...THOUGH COOL SSTS MAY TEMPER THE 
INCREASE IN WINDS SOMEWHAT AT THE SURFACE EARLY IN THE NIGHT. THIS 
EFFECT HOWEVER WILL BE OVERWHELMED TOWARDS THE END OF THE PERIOD BY 
THE OVERALL INCREASE IN MOMENTUM OF THE ATMOSPHERE AND A SMALL CRAFT 
ADVISORY WILL BE NEEDED. 

LONG TERM /WEDNESDAY THROUGH THURSDAY/...
AS OF 3 AM SUNDAY...STRONGLY FORCED COLD FRONT APPROACHING ON 
WEDNESDAY AND SOLID SMALL CRAFT ADVISORY IN EFFECT. SUSTAINED GALE 
FORCED WINDS WILL BE LURKING NOT TOO FAR ABOVE THE SURFACE AND AS 
THE EVENT GETS CLOSER ATTENTION WILL SHIFT TO HOW DEEP MOMENTUM 
TRANSFER OVER THE COOL SSTS WILL BE. SHOULD MIXING OVERWHELM THE 
STABILIZING EFFECT OF THE COOL WATERS THEN WINDS MAY BE HIGHER THAN 
CURRENTLY FORECAST, ALTHOUGH SURFACE GALES STILL SEEM RATHER 
UNLIKELY. SHARP VEER WED NIGHT WITH FROPA AND BOUNDARY LAYER WIND 
SPEEDS DROP OFF CONSIDERABLY BY THURSDAY.

&&

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

&&

$$

SYNOPSIS...MBB
NEAR TERM...REK
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...BJR

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