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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KILM 151922
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
320 PM EDT SAT MAR 15 2014

.SYNOPSIS...
A STORM SYSTEM MOVING EAST ACROSS THE GULF STATES...WILL BRING
PERIODS OF RAIN TO THE CAROLINAS SUNDAY THROUGH TUESDAY. FAIR
AND SEASONABLE CONDITIONS ARE EXPECTED WEDNESDAY THROUGH FRIDAY.
A COLD FRONT WILL IMPACT THE EASTERN CAROLINAS NEXT WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 235 PM SATURDAY...AS EXPECTED THE REGION HAS WARMED INTO THE
70S...THOUGH SOME AREAS ARE ON TRACK TO END UP A BIT WARMER THAN
FIRST THOUGHT. WINDS REMAIN ON THE GUSTY SIDE DESPITE THE
SHORTWAVE PUSHING FARTHER OFF THE COAST. WHILE THE SHORTWAVE WAS
ENHANCING WIND SPEEDS THIS MORNING DIURNAL HEATING AND MIXING HAS
TAKEN OVER AS THE MAIN REASON BEHIND THE GUSTY WINDS. FORECAST
SOUNDINGS DO WEAKEN WINDS AT THE TOP OF THE MIXED LAYER THIS
AFTERNOON AND GUSTS SHOULD DECREASE IN BOTH STRENGTH AND
FREQUENCY.

TONIGHT A COLD FRONT WILL DROP IN FROM THE NORTH THEN STALL IN THE
VICINITY. FRONT ENDS UP FAR ENOUGH SOUTH EARLY SUN THAT NORTHEAST
FLOW IS ABLE TO SETUP OVER THE FORECAST AREA. ALTHOUGH THE COLDEST
AIR REMAINS NORTH OF THE AREA THE NORTHEAST FLOW WILL PUSH A
SLIGHTLY COOLER AIRMASS INTO THE REGION. LOW LEVEL NORTHEAST FLOW
AND COOL BOUNDARY LAYER WILL LEAD TO INCREASING ISENTROPIC LIFT.
MID LEVEL FLOW STARTS TO INCREASE AFTER MIDNIGHT AS SOUTHERN
STREAM SYSTEM MOVES EAST INTO THE LOWER MS VALLEY. SIGNIFICANT
INCREASE IN MID LEVEL MOISTURE WILL LEAD TO FULL OVERCAST BEFORE
THE END OF THE PERIOD BUT LOW LEVEL DRY AIR...UP TO ABOUT 5K
FT...IS LIKELY TO KEEP THE REGION FREE OF MEASURABLE RAIN THROUGH
12Z SUN. HAVE SCALED BACK POP TO ONLY SLIGHT CHANCE ACROSS INLAND
SC LATE IN THE PERIOD.

ALTHOUGH COLD FRONT DROPS IN FROM THE NORTH TONIGHT THERE IS A
LACK OF NOTICEABLE COLD ADVECTION BEHIND IT. TEMPS WILL DROP A BIT
BUT BOUNDARY LAYER MIXING AND INCREASING CLOUD COVER AFTER
MIDNIGHT ARE LIKELY TO OFFSET ANY WEAK COLD ADVECTION. GIVEN THE
WARMER TEMPS THAN FORECAST THIS AFTERNOON WILL KEEP LOWS NEAR OR
ABOVE THE HIGH END OF GUIDANCE.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 235 PM SATURDAY...A GOOD SOAKING RAIN EVENT UPCOMING STARTING
SUNDAY AND POTENTIALLY QUITE AN EXPLOSIVE SPRING FOLIAGE-WISE...AS
RAIN AMOUNTS OF 1-2 INCHES ARE PROJECTED BY THE HYDRO-PREDICTION
CENTER FOR THE PERIOD SUNDAY THROUGH DAYBREAK TUESDAY.

CANOPY OF CLOUDS ALREADY ADVANCING TO THE COAST DAYBREAK SUNDAY
INTO THE AREA AS A GULF SYSTEM APPROACHES. ONSET OF RAIN HOWEVER
MAY REQUIRE A PERIOD OF VIRGA EARLY SUNDAY TO OVERCOME THE DRY
LOW LEVEL AIR...AS STRATIFORM AND OVER-RUNNING INITIALLY GEAR-UP.

THE CLOUDS AND RAIN WILL SQUISH THE DIURNAL TEMPERATURE RANGES
SUNDAY AND MONDAY...AND MAX/MINS MAY ONLY BE SEPARATED BY 10
DEGREES OR LESS IN SOME SPOTS...HOLDING BETWEEN 50-60 MUCH OF THE
PERIOD OVER OUR FORECAST AREA. THEN EARLY TUESDAY SOMETIME AFTER
6Z-9Z COLD AIR BEGINS TO WORK INTO THE CAROLINAS AND TEMPERATURES
DROP MORE SHARPLY.

TSTM INGREDIENTS LACKING OVERALL...BUT SUNDAY NIGHT SLIGHT CHANCE
TSTMS WAS INTRODUCED TO THE COASTAL WATERS...ALTHOUGH NEAR SHORE
IT IS LESS LIKELY DUE TO COLDER OCEAN TEMPS. SUNDAY NIGHT ELEVATED
CAPE VALUES INCREASE OFFSHORE AS SHORT-WAVE ENERGY MOVES ALONG OUR
COAST.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
AS OF 300 PM SATURDAY...SHORTWAVE STRETCHED DOWN ALONG THE SOUTHEAST
COAST EARLY TUES MORNING WILL EXIT THE COAST MOVING AWAY FROM AREA
THROUGH THE DAY ON TUES. THIS WILL LEAVE A RIDGE BUILDING IN BEHIND
IT THROUGH THE MID TO UPPER LEVELS OF THE ATMOSPHERE WHILE SFC HIGH
WILL BE WEDGED DOWN THROUGH INLAND CAROLINAS FROM NEW ENGLAND.
MOISTURE THROUGH THE COLUMN WILL DECREASE THROUGH LATE TUES INTO
WED...MOST NOTABLY THROUGH THE MID TO UPPER LEVELS IN A DRY WESTERLY
FLOW ABOVE H70. UNFORTUNATELY...MOISTURE WILL REMAIN LOCKED IN AS
VERY SHALLOW COOL AIR IS BEING OVERRUN BY MUCH WARMER AIR IN THE
LOWER LEVELS ABOVE 1K FT. THEREFORE WILL KEEP CLOUDS AND CHC OF PCP
THROUGH TUES INTO WED WITH LOW END QPF TUES AFTERNOON THROUGH WED.
STRONGER NORTHERLY FLOW IN A PINCHED GRADIENT EARLY TUES WILL COME
AROUND AND LIGHTEN THROUGH WED.

WEDGE FINALLY BREAKS AS NEXT NORTHERN STREAM SYSTEM PUSHES EAST
ACROSS THE GREAT LAKES WED. WINDS COME AROUND TO THE SOUTH AS
TRAILING COLD FRONT ASSOCIATED WITH THIS NORTHERN STREAM SYSTEM
MAKES ITS WAY EAST THROUGH WED MOVING OFF THE COAST WED NIGHT. HIGH
PRESSURE WILL BUILD IN BEHIND IT THROUGH THURS INTO THE FIRST HALF
OF THE WEEKEND. THEREFORE A DEEPER NW FLOW WILL SET UP OVERNIGHT WED
INTO THURS WITH PLENTY OF DRY AIR AND SUBSIDENCE SCOURING OUT ANY
LINGERING MOISTURE. ANOTHER WEAK SHORTWAVE MAY PRODUCE SOME PASSING
HIGH CLOUDS AS IT MOVES THROUGH THURS NIGHT...BUT OVERALL EXPECT
SUNSHINE THURS THROUGH EARLY SAT BEFORE CLOUDS AND PCP CHANCES
INCREASE ONCE AGAIN AS COLD FRONT APPROACHES LATE SATURDAY.

CLOUDS...PCP AND COOL NORTHERLY FLOW WILL KEEP TEMPS BELOW NORMAL
TUES. AS WEDGE BREAKS ON WED...WINDS WILL COME AROUND ALLOWING TEMPS
TO WARM BUT CLOUDS SHOULD HOLD HIGH TEMPS BETWEEN 60 AND 65 MOST
PLACES. SUNSHINE AND DRY AIR ALONG WITH DEEP WESTERLY DOWNSLOPE FLOW
WILL BRING TEMPS ABOVE NORMAL THURS AND FRI AND  INTO SATURDAY.
-- End Changed Discussion --

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
AS OF 18Z...HIGH CONFIDENCE VFR WILL PREVAIL THROUGH 12Z SUNDAY.
SCT MID/THIN BKN HIGH CLOUDS EXPECTED THIS AFTERNOON WITH SW WINDS
10-18 KTS WITH OCCASIONAL HIGHER GUSTS. WINDS WILL BECOME LGT/VRBL
EARLY THIS EVENING. MID-LEVEL CIGS WILL DEVELOP LATE THIS EVENING
AS A WEAK COLD FRONT DROPS S THROUGH THE TERMINALS. MID-LEVEL CIGS
LOWER TO 6-8K BY 12Z. ALTHOUGH THERE IS A SLIGHT CHANCE OF RAIN AT
KMYR/KCRE/KFLO AFTER 09Z...BETTER CHANCES WILL BE AFTER 12Z. THERE
IS AN INCREASING CHANCE OF MVFR CIGS/VSBYS AFTER 12Z. THE CHANCE
OF ANY IFR DURING THIS TIME IS LOW.

EXTENDED OUTLOOK...EXPECT RAIN/IFR CONDITIONS SUNDAY AFTERNOON INTO
TUESDAY...EXCEPT RAIN WILL BE LIGHT WITH MVFR CIGS MONDAY. LIGHT
RAIN/MVFR CIGS WEDNESDAY. VFR DEVELOPING THURSDAY.

&&

.MARINE...
-- Changed Discussion --
NEAR TERM /THROUGH TONIGHT/...
AS OF 235 PM SATURDAY...PINCHED GRADIENT KEEPING SOUTHWEST FLOW A
LITTLE HIGHER THAN EXPECTED BUT NOT ENOUGH TO HAVE SIGNIFICANT
IMPACT ON SEAS. WINDS WILL SLOWLY DECREASE THROUGH AFTERNOON AS
WILL THE GUSTS. FLOW WILL REMAIN SOUTHWEST INTO TONIGHT BEFORE
COLD FRONT DROPPING IN FROM THE NORTH DEVELOPS EAST-NORTHEAST FLOW
OVER THE WATERS. PROXIMITY TO THE FRONT WILL KEEP SPEEDS AT OR
BELOW 10 KT WITH WINDS REMAINING NORTHEAST TO EAST THROUGH THE END
OF THE PERIOD. SEAS CONTINUE TO RUN 2 TO 4 FT THIS AFTERNOON BUT
WILL DROP TO 2 TO 3 FT TONIGHT AND 2 FT OR LESS BY THE END OF THE
PERIOD.

SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 235 PM SATURDAY...MARINE CONDITIONS WILL DETERIORATE ON SUNDAY
AND IMPROVEMENT WILL NOT BE SEEN UNTIL SOMETIME ON TUESDAY AS A
GULF STORM RAKES ACROSS OUR COAST DURING THIS PERIOD. INTENSIFYING
SW WIND SUNDAY WILL SHIFT TO BLUSTERY N-NNE WINDS AROUND DAYBREAK
MONDAY AS THE SURFACE LOW PULLS OFF TO THE NE. THIS WILL BE
FOLLOWED BY A WEDGE INTRUSION FROM THE NORTH THAT WILL RE-ASSERT
TO KICK UP LOCAL NE WINDS...SUSTAINING THE ADVISORIES BEYOND DAWN
ON TUESDAY. A FEW GALE GUSTS OUTER WATERS SUNDAY NIGHT POSSIBLE.
THE SEA SPECTRUM WILL SEE INCREASING S WAVES SUNDAY...FOLLOWED BY
PITCHY AND CONFUSED WAVES MONDAY AS N WIND RIPS ACROSS THE RESIDUAL
S WAVE ENERGY. HAZARDOUS MARINE CONDITIONS TO PREVAIL ALL OF SUNDAY
AND MONDAY.

LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 300 PM SATURDAY...SHORTWAVE WILL EXIT THE COAST ON TUES BUT
STRONGER NE FLOW IN PINCHED GRADIENT WILL CONTINUE AS HIGH PRESSURE
REMAINS WEDGED DOWN THROUGH THE INLAND CAROLINAS. THIS INCREASED
NORTHERLY FLOW WILL WEAKEN AND COME AROUND TO THE S-SE AS WEDGE
FINALLY BREAKS AHEAD OF WEAK COLD FRONT TRAILING DOWN FROM A
NORTHERN STREAM SYSTEM ON WED. WINDS UP TO 15 TO 25 KTS TUES INTO
EARLY WED IN WEDGE WILL FINALLY COME DOWN BY THURS AS NORTHERLY FLOW
LIGHTENS AS HIGH PRESSURE SHIFTS CLOSER OVERHEAD.

SEAS UP INTO SCA THRESHOLDS WILL COME DOWN AS WINDS DIMINISH DOWN TO
10 TO 15 KTS AND SHIFT TO THE NORTH WED NIGHT INTO THURS BEHIND WEAK
FRONT AS HIGH PRESSURE BUILDS IN. BY THURS AFTN SEAS WILL BE DOWN TO
2 TO 4 FT IN WINDS DOWN TO 10 KTS OR LESS.
-- End Changed Discussion --

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 9 PM SUNDAY TO NOON EDT TUESDAY FOR
         AMZ250-252-254-256.

&&

$$

NEAR TERM...III
SHORT TERM...MJC
LONG TERM...RGZ
AVIATION...MRR/III