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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KILM 072300
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
600 PM EST FRI MAR 7 2014

.SYNOPSIS...
RAINFALL WILL COME TO AN END AND STRONG WINDS WILL DIMINISH AS STRONG
LOW PRESSURE ALONG THE NORTH CAROLINA COAST THIS AFTERNOON MOVES
OUT TO SEA THROUGH TONIGHT. HIGH PRESSURE WILL BUILD IN FOR THE
WEEKEND BRINGING DRY AND MUCH WARMER CONDITIONS. DRY WEATHER WILL
CONTINUE THROUGH TUESDAY. A COLD FRONT WILL MOVE THROUGH DURING
THE MIDDLE OF NEXT WEEK BRINGING A RISK FOR SHOWERS. HIGH PRESSURE
AND DRY WEATHER WILL RETURN BY LATE NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 3 PM FRIDAY...DEEPENING SURFACE LOW PRESSURE IS SOUTH OF CAPE
HATTERAS THIS AFTERNOON AS THE UPPER LOW PASSES ALMOST DIRECTLY OVER
CAPE FEAR. LOW CLOUDS WILL CONTINUE ACROSS THE EASTERN CAROLINAS
THROUGH AT LEAST MIDNIGHT BEFORE DRIER AIR DOWNSLOPING OFF THE NC/VA
MOUNTAINS ARRIVES ON NORTHERLY WINDS.

SHOWERS CONTINUE TO PLAGUE MOST OF THE AREA NORTH OF A LINE FROM
FLORENCE AND MARION TO CONWAY AND SOUTHPORT. THESE SHOWERS ARE
SUPPORTED BY AN INCREASINGLY SHALLOW LAYER OF ISENTROPIC LIFT...NOW
DESCENDING THROUGH THE 290-295K SURFACES...APPROXIMATELY 3500-5500
FT AGL. THIS IS A REGION OF RELATIVELY WARM EASTERLY FLOW OFF THE
ATLANTIC THAT SHOULD DIMINISH RATHER ABRUPTLY OVER THE NEXT FEW
HOURS AS THE MID AND UPPER LEVEL LOWS PUSH OFFSHORE AND WINDS BACK
NORTHERLY WITHIN THIS LAYER. IN FACT AROUND 00Z ISENTROPIC LIFT
CEASES TO EXIST AND ALL I CAN FIND IN MODEL FORECASTS IS VARYING
DEGREES OF DOWNGLIDE. THIS SHOULD LEAD TO A RAPID EROSION OF SHOWERS
AFTER 00Z...WITH DRY WEATHER EXPECTED OVERNIGHT.

SKIES WILL PROBABLY BECOME CLEAR BETWEEN 05-08Z...WITH A THIN LAYER
OF RESIDUAL MOISTURE POTENTIALLY CREATING PATCHES OF LOW STRATUS
LATE TONIGHT...OR FOG IF WINDS CAN DIMINISH SUFFICIENTLY. FOR NOW I
AM CONFINING FOG POTENTIAL TO THE I-95 CORRIDOR VERY LATE TONIGHT...
AS THIS REGION WILL HAVE THE LOWEST SHEAR WITHIN THE SURFACE-1000 FT
LAYER AND THEREFORE THE GREATEST POTENTIAL FOR FOG. LOWS SHOULD FALL
VERY NEAR FREEZING INLAND...WITH MID TO UPPER 30S ALONG THE COAST.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 3 PM FRIDAY...RIDGE OF HIGH PRESSURE WILL BUILD IN BEHIND
DEPARTING LOW PRESSURE SYSTEM THROUGH SATURDAY. NORTHERLY WINDS
WILL LIGHTEN AND BACK TOWARD THE WEST AS CENTER OF HIGH REMAINS
TO THE SOUTH OF THE CAROLINAS AND GRADIENT RELAXES ON SAT. OVERALL
EXPECT A DEEP DRY NORTHERLY FLOW ON THE BACK END OF THE LOW TO
HELP SCOUR OUT ANY LINGERING MOISTURE AND ALLOW SUNSHINE TO
BE PLENTIFUL SATURDAY. BUILDING HEIGHTS AND WESTERLY DOWNSLOPE
FLOW WILL HELP TO KICK TEMPS BACK UP TO NORMAL...MID 60S MOST
PLACES. THE WESTERLY FLOW...ALTHOUGH LIGHTENING...SHOULD HELP TO
KEEP SEA BREEZE CLOSE TO THE COAST. THE COOL SHELF WATERS WILL
MAINTAIN COOLER TEMPS ALONG THE BEACHES.

THE MID TO UPPER RIDGE FLATTENS OUT SAT NIGHT INTO SUNDAY BEFORE A
STRETCHED OUT W-E ORIENTED SHORTWAVE STREAMS ACROSS THE AREA SUN
NIGHT. THIS SHORTWAVE WILL PUSH A WEAK COLD FRONT THROUGH THE
COASTAL CAROLINAS ON SUNDAY. THE WINDS WILL BACK SLIGHTLY AHEAD
OF IT AND VEER AROUND TO THE NW BEHIND IT BUT OVERALL NOT MUCH OF
AN EFFECT ON THE WEATHER ASIDE FROM SOME PASSING CLOUDS. OVERALL
EXPECT SUNDAY TO BE A FEW DEGREES WARMER WITH LIGHT W FLOW. SHOULD
SEE INCREASE IN CLOUDS ASSOCIATED WITH FRONT AND SHORTWAVE BUT
OTHERWISE NO POPS IN FORECAST FOR THE WEEKEND.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 3 PM FRIDAY...ABOVE NORMAL TEMPERATURES TO START THE PERIOD
AS SPRING FINALLY MAKES AN APPEARANCE ACROSS THE CAROLINAS. 5H
PATTERN BECOMES RATHER FLAT ACROSS THE REGION EARLY WEEK AS
CONFLUENCE BETWEEN NORTHERN STREAM TROUGH AND SOUTHERN STREAM
RIDGE DRIVES A VORT STREAMER OVERHEAD. THIS HELPS REINFORCE HIGH
PRESSURE AT THE SURFACE...WHICH SPREADS INCREASINGLY WARM AND
MOIST AIR INTO THE CAROLINAS ON RETURN FLOW. HIGHS MON/TUE WILL
LIKELY BE WELL ABOVE NORMAL...WITH WIDESPREAD LOW AND EVEN MID 70S
EXPECTED EARLY WEEK.

FORECAST BECOMES MORE COMPLEX WED/THU AS A LOW PRESSURE SYSTEM EXITS
FROM NORTH TEXAS AND MOVES NORTHEAST TO OFF THE MID-ATLANTIC COAST
THURSDAY MORNING. THIS IS A COMPLEX LOW PRESSURE SYSTEM THANKS TO
TWO DISTINCT MID-LEVEL IMPULSES...ONE OF WHICH RACES ACROSS THE GULF
COAST...WHILE THE OTHER DROPS INTO THE OH VLY. AT THIS TIME...THE
SURFACE LOW IS PROGGED TO REMAIN RATHER WEAK...BUT WILL TRAVERSE
JUST NW OF THE LOCAL AREA. THIS IS A LOCATION THAT CAN SOMETIMES
CREATE CONVECTION LOCALLY AS THE AREA GETS WARM SECTORED WITH
INCREASED LOW-LEVEL SHEAR. ALTHOUGH IT IS STILL SEVERAL DAYS
OUT...INSTABILITY AND SHEAR ARE FORECAST TO REMAIN QUITE WEAK WITH
THIS EVENT...SO WILL KEEP WX-TYPE AS -RW INSTEAD OF -TRW FOR
NOW...BUT NOTE THAT POTENTIAL FOR CONVECTION DOES EXIST ON
WEDNESDAY. AS THE LOW PULLS AWAY INTO THURSDAY...THE NORTHERN STREAM
TROUGH HANGS BEHIND AND SOME PRECIP MAY LINGER INTO THURSDAY. THE
ECMWF IS SLOWER THAN THE GFS...AND BASED OFF THE LACK OF MID-LEVEL
AMPLIFICATION EXPECT THE GFS IS A BETTER FIT...BUT WILL MAINTAIN
INHERITED SCHC POP INTO THURSDAY UNTIL MODELS SHOW BETTER AGREEMENT.

REGARDLESS OF WHICH SOLUTION TURNS OUT TO BE CORRECT IN TERMS OF
STRENGTH AND TIMING...COLD FRONT CROSSES THE AREA OVERNIGHT/EARLY
THURSDAY...WITH MUCH COLDER AIR RETURNING FOR THE END OF THE WEEK AS
TEMPS CRASH TO WELL BELOW CLIMO ONCE AGAIN.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
AS OF 00Z...UPPER LOW BEGINNING TO PULL AWAY. STILL A LOT OF CLOUDS
AROUND...HOWEVER DERIVED SOUNDINGS SHOW SIGNIFICANT DRYING BY
03-04Z...WITH STRONG SUBSIDENCE AFTER 06Z. LOOK FOR PRECIP TO BE
NEARLY GONE BY 01Z...WITH CLEARING SKIES AFTER 04Z. THIS POSES A
PROBLEM FOR FOG. WE WILL NOT COMPLETELY DECOUPLE...BUT WILL PROBABLY
SEE POCKETS OF MVFR/IFR FOG AFTER 06Z. SATURDAY...A MUCH NEEDED
BEAUTIFUL DAY WITH NEARLY CLEAR SKIES AND A FAIRLY LIGHT WEST
NORTHWEST WIND. TEMPS WILL PROBABLY GET WARM ENOUGH FOR A RESULTANT
TO SET UP...WITH SOUTHERLY WINDS EXPECTED AT THE COAST IN THE
AFTERNOON.

EXTENDED OUTLOOK...VFR WILL PREVAIL THROUGH TUESDAY. CHANCE OF
SHOWERS ON WEDNESDAY.
-- End Changed Discussion --

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 3 PM FRIDAY...DEEPENING LOW PRESSURE SOUTH OF HATTERAS WILL
CONTINUE TO MOVE EAST AND OUT TO SEA TONIGHT. ONE LAST BOUT OF
STRONG NORTHERLY WINDS SHOULD OCCUR LATE THIS AFTERNOON AS THE MID
AND UPPER LEVEL LOW PRESSURE CENTERS MOVE OFFSHORE AND COLDER AIR
SURGES OFFSHORE. FOR THIS REASON I AM MAINTAINING THE GALE WARNING
(MAINLY FOR GUSTS) FOR THE CAPE FEAR AREA WATERS THROUGH 6 PM. AFTER
6 PM IT SHOULD BE ABLE TO BE REPLACED WITH A SMALL CRAFT ADVISORY
LIKE THE SOUTH CAROLINA WATERS AS WINDS AND SEAS GRADUALLY DIMINISH.
IMPROVING MARINE CONDITIONS SHOULD DEVELOP LATER TONIGHT AND LAST
FOR THE NEXT SEVERAL DAYS.

SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 3 PM FRIDAY...QUIET WEEKEND AHEAD. HIGH PRESSURE BUILDS IN
WITH DIMINISHING WINDS ON SATURDAY. WESTERLY OFF SHORE FLOW WILL
ALLOW SEAS TO SUBSIDE TO 3 FT OR LESS BY AFTN. A WEAK FRONT WILL
PASS THROUGH ON SUNDAY. A SLIGHT BACKING AND INCREASE IN WINDS ON
SUNDAY AS FRONT APPROACHES AND THEN VEERING TO THE NW BEHIND IT...
BUT OVERALL BENIGN MARINE CONDITIONS.

LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 3 PM FRIDAY...BROAD AREA OF HIGH PRESSURE WILL DRIFT SOUTH
OF THE AREA FROM WEST TO EAST EARLY IN THE WEEK...CREATING W/SW
WINDS OF 10-15 KTS MONDAY AND TUESDAY WITH LITTLE VARIATION.
WITHOUT ANY MEANINGFUL SWELL WITHIN THE WAVE SPECTRUM...WAVE
HEIGHTS WILL BE 1-3 FT MONDAY...2-4 FT ON TUESDAY...WITH A W/SW
WIND CHOP THE ONLY SIGNIFICANT WAVE GROUP. LOW PRESSURE AREA WILL
MOVE NW OF THE WATERS ON WEDNESDAY...DRIVING A PINCHED GRADIENT
AND SW WINDS INCREASING TO 15-20 KTS LATE WEDNESDAY...BEFORE
VEERING QUICKLY TO THE NW BEHIND A COLD FRONT AT THE END OF THE
PERIOD. SEAS WILL RISE BRIEFLY TO 3-5 FT WEDNESDAY NIGHT AHEAD OF
THE COLD FRONT...BEFORE RAPIDLY FALLING BACK TO 2-4 FT ON THE
OFFSHORE WIND COMPONENT BY THURSDAY MORNING.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR AMZ254-256.

     GALE WARNING UNTIL 6 PM EST THIS EVENING FOR AMZ250-252.

&&

$$

NEAR TERM...TRA
SHORT TERM...RGZ
LONG TERM...JDW
AVIATION...43