-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KILM 241729
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
129 PM EDT FRI MAY 24 2013

.SYNOPSIS...
A COLD FRONT WILL BRING COOLER AND DRIER AIR INTO THE REGION TODAY
AND THROUGH THE WEEKEND. A GRADUAL WARMUP WILL BEGIN ON MONDAY WITH
SEASONABLE TEMPERATURES EXPECTED FOR MUCH OF THE NEXT COMING WEEK.
NO SIGNIFICANT RAINFALL CHANCES ARE EXPECTED IN THE EXTENDED PERIOD.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 12:30 PM FRIDAY...EXTENSIVE CLOUD FIELD HAS DEVELOPED AS
EXPECTED. SOME LIGHT RADAR RETURNS JUST NORTH OF THE CWA HINT AT
POSSIBLE ISOLATED SHOWER ACTIVITY IN STORE FOR THIS AFTERNOON AS
DESCRIBED IN PREVIOUS DISCUSSION BELOW. HOWEVER...WITH DEWPOINTS
DROPPING...ANY SHOWER ACTIVITY WOULD HAVE TO DEVELOP IN THE NEXT
FEW HOURS. IF NOT...WILL BE REVISING FORECAST TO TAKE ANY POSSIBLE
PRECIPITATION OUT OF THE PICTURE. RELEVANT PORTION OF PREVIOUS
DISCUSSION...AS MODIFIED...FOLLOWS BELOW:

EAST-BOUND COLD FRONT NOW WELL OFFSHORE. DEWPOINTS ARE FALLING
STEADILY AS CANADIAN HIGH PRESSURE SYSTEM BUILDS IN. STEEP LAPSE
RATES AS UPPER TROUGH SWINGS OVERHEAD AND RESIDUAL LOW-LEVEL
MOISTURE ACROSS THE EASTERN HALF OF OUR FORECAST ZONES MAY COMBINE
TO SET OFF A FEW SHOWERS EARLY THIS AFTERNOON.

DRYING AND CLEARING TONIGHT IS EXPECTED AND MINIMUM TEMPERATURES
BY DAYBREAK MAY APPROACH RECORD LOW VALUES. RECORD LOWS FOR MAY
25TH ARE ILM-50 LBT-45 FLO-48 MYR-52 AND CRE-55.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 3 AM FRIDAY...AFTER AN UNSEASONABLY CHILLY START SATURDAY WILL
TURN OUT PLEASANT WITH FULL SUNSHINE AND FAIRLY LIGHT WINDS. THESE
WINDS WILL STILL BE OUT OF THE N TO NW HOWEVER KEEPING DAYTIME HIGHS
OVER A CATEGORY BELOW CLIMO THANKS TO CUTOFF UPPER LOW/OCCLUDED
CYCLONE NEAR NANTUCKET. AS THE CAA SHUTS OFF TO NEUTRAL AND A SMALL
INCREASE IN CLOUD COVER OCCURS SAT NIGHT TEMPERATURES WILL DIP DOWN
TO WITHIN A FEW DEGREES OF 50...NOT QUITE AS COOL AS THE PREVIOUS
NIGHT. VERY WEAK WAA ON SUNDAY TO ADD A FEW DEGREES TO HIGHS AS WELL
AS GENERATE A LITTLE CLOUD COVER BUT STILL LOOKING AT ABOUT 5 DEG
SHY OF SEASONABLE TEMPS. A CONTINUATION OF BELOW NORMAL TEMPERATURES
ROUNDS OUT THE PERIOD WITH LOWS IN THE LOW TO MID 50S SUNDAY NIGHT.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 3 AM FRIDAY...RETURN FLOW SETS UP TO START NEXT WEEK ALBEIT
SOMEWHAT WEAKLY ON MONDAY AND HIGHS MAY STILL END UP A FEW DEG BELOW
CLIMO. INCREASING DEWPOINTS WILL BE NOTICEABLE TOO IN THE ONSHORE
FLOW. TUESDAY INTO WEDNESDAY WILL BRING A SIGNIFICANT BUILDING OF
THE UPPER RIDGE ACROSS THE EASTERN U.S. WHILE HIGH PRESSURE SPRAWLS
ACROSS THE WESTERN ATLANTIC. THE AMPLITUDE OF THE UPPER RIDGE
CERTAINLY ARGUES FOR UNSEASONABLE WARMTH BUT THE RIDGE AXIS JUST N
OF THE REGION WILL KEEP A DEEP EASTERLY FLOW INTO THE CAROLINAS.
THAT IS...THE SOUTHERLY COMPONENT WILL BE MINIMIZED MUCH OF THE
TIME. THE COOLER SHELF WATERS SHOULD THUS HAVE A MODERATING EFFECT
ON THE WARMTH...MOST PRONOUNCED NEAR THE COAST. THE CAPPING EFFECT
OF THE THE RIDGE PAIRED WITH THE STABILIZING EFFECTS OF THE SURFACE
MARINE AIR WILL KEEP MEANINGFUL RAIN CHANCES OUT OF THE FORECAST.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
AS OF 18Z...THERE MAY BE ENOUGH INSTABILITY TO KICK OFF SOME
ISOLATED SHOWERS...MAINLY AROUND THE CAPE FEAR REGION.
OTHERWISE...HIGH CONFIDENCE FOR VFR CONDITIONS. HIGH PRESSURE
BUILDING IN THIS AFTERNOON WITH GUSTY NORTHWEST WINDS. WINDS
DIMINISH THIS EVENING AS GRADIENT SLACKENS AND DIURNAL CONDITIONS
SET UP. SATURDAY...A BEAUTIFUL DAY WITH NEARLY CLEAR SKIES AND A
MODERATE NORTH WIND.

EXTENDED OUTLOOK...A SLIGHT CHANCE FOR SHOWERS SUNDAY THROUGH
TUESDAY. MORNING FOG POSSIBLE TUESDAY AND WEDNESDAY.
-- End Changed Discussion --

&&

.MARINE...
-- Changed Discussion --
NEAR TERM /THROUGH TONIGHT/...
AS OF 12:30 PM FRIDAY...NO CHANGES TO THE FORECAST WITH THE LATEST
UPDATE. KEEPING SMALL CRAFT ADVISORY IN PLACE FOR THIS AFTERNOON
AND EVENING FOR GUSTS TO AROUND 25 KTS. WINDS STILL AT SUB-
ADVISORY LEVELS NOW BUT HAVE PICKED UP A BIT NOW THAT THE COLD
FRONT HAS MOVED ACROSS THE WATERS. LATEST OBS SHOW NW WINDS OF 10
TO 15 KTS WITH 3 TO 4 FT SEAS. PREVIOUS DISCUSSION FOLLOWS:

SMALL CRAFT ADVISORY FLAGS HOISTED FOR ALL OF OUR SE NC AND NE SC
WATERS FROM 3PM-9PM TODAY...TO ADDRESS 25 KT NW WIND GUSTS
ANTICIPATED LATER TODAY INTO TONIGHT. SEAS GENERALLY WILL HOLD 3-4
FEET MOST WATERS BUT UP TO 5-6 FT ALONG OUTER PORTION SUBJECTED TO
LONGER FETCH BUILD-UP. TSTMS MAY ALSO BE EXPECTED BUT MAINLY
CONFINED ALONG THE WEST WALL OF THE GULF STREAM CURRENT TODAY AND
TONIGHT. PEAK WINDS NNW 15-25 KT ARE EXPECTED BETWEEN 5 PM- 8PM AS
THE DEPARTING FRONT AND ENCROACHING HIGH PRESSURE HAVE THE
GREATEST SFC PRESSURE GRADIENT INTERACTION. SEAS WILL TAKE ON A
BUMPY CHARACTER TODAY AS RESIDUAL SE WAVE ENERGY BORN FROM
OFFSHORE BERMUDA HIGH PRESSURE CONTENDS WITH INCREASING WIND-WAVES
OPPOSING FROM THE NW.

SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 3 AM FRIDAY...PLEASANT BOATING CONDITIONS EXPECTED THROUGH THE
PERIOD. HIGH PRESSURE BUILDING IN GRADUALLY FROM THE N TO KEEP A N
TO NW WIND THROUGH THE PERIOD THAT WILL BE CAPPED AT 10KT DUE TO A
FAIRLY WEAK GRADIENT. THE STORM HELPING TO DRIVE THE HIGH WILL BE
ALL THE WAY UP NEAR NANTUCKET ON SATURDAY AND ONLY GRADUALLY
LIFTING INTO NOVA SCOTIA CANADA INTO SUNDAY. SOME BACKSWELL FROM
THIS SYSTEM WILL BE INTERCEPTED BY CAPE HATTERAS AND NOT MUCH
SHOULD MAKE IT THIS FAR SOUTH DUE TO WAVE SHADOWING. THUS EXPECT
FAIRLY SMALL SEAS TO THE TUNE OF 2 FT OR LESS THROUGH THE
PERIOD...WITH THE SMALLEST WAVES OFF OF BRUNSWICK COUNTY WHERE
OFFSHORE FLOW COMPONENT IS MAXED.

LONG TERM /MONDAY THROUGH TUESDAY/...
AS OF 3 AM FRIDAY...WEAK RETURN FLOW SETS UP ON MONDAY AS HIGH
PRESSURE FINALLY ESTABLISHES CENTER OFF THE COAST. ITS PROXIMITY
TO THE LANDMASS WILL KEEP WIND SPEEDS AT 10 KT OR LESS AND IN THE
ABSENCE OF SWELL ENERGY THE DIMINUTIVE WIND WAVE OF 2 FT OR LESS
WILL BE THE PREDOMINANT WAVE. THE WEST ATLANTIC HIGH BECOMES
LARGER INTO TUESDAY MAKING ITS CENTER FARTHER WAY BUT LEADING TO
LITTLE CHANGE IN LOCAL WIND FLOW. DEEP AND LONG FETCH EASTERLY
SWELL WILL BE GETTING ESTABLISHED INTO THE BAHAMAS AND THIS WILL
LIKELY START TO GENERATE SOME SWELL ENERGY INTO THE CAROLINAS BUT
NOT UNTIL AFTER THE PERIOD.
-- End Changed Discussion --

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 9 PM EDT THIS EVENING FOR AMZ250-
     252-254-256.

&&

$$

SYNOPSIS...MBB
NEAR TERM...MJC/REK
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...DL
MARINE...MJC/REK/MBB