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000
FXUS62 KILM 180704
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
304 AM EDT TUE JUN 18 2013

.SYNOPSIS...
WARM AND HUMID CONDITIONS WILL PREVAIL AHEAD OF AN APPROACHING COLD
FRONT...WHICH WILL MOVE THROUGH THE AREA WEDNESDAY.  HIGH PRESSURE
WILL BUILD IN FROM THE NORTH WITH A DRYING TREND THE WILL BEGIN
TOWARD THE END OF THE WEEK AND LAST INTO EARLY NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 3 AM TUESDAY...A COLD FRONT WILL APPROACH FROM THE NW TODAY
AND MOVE INTO THE AREA TONIGHT.  IN ADVANCE OF THE FRONT EXPECT TO
SEE SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS...PARTICULARLY
DURING THE AFTERNOON AND EVENING HOURS. ONCE CURRENT ACTIVITY CLEARS
THE COAST...PLAN ON CHC POPS THROUGH THE PERIOD EXCEPT FOR LIKELY
POPS FROM ABOUT MIDDAY INTO THE EVENING HOURS.  MAX TEMPERATURES
TODAY SHOULD REACH THE MID 80S WITH LOWS TONIGHT WITHIN A COUPLE
DEGREES OF 70.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 AM TUESDAY...FRONT IN THE AREA AT THE START OF THE PERIOD
WILL BE PUSHED FARTHER EAST BY WESTERLY FLOW ALOFT AND SURFACE HIGH
RIDGING DOWN THE COAST DURING THE PERIOD. GFS/WRF/ECMWF ALL SHOW
DRIER MID LEVEL AIR MOVING INTO THE REGION AS EARLY AS WED AFTERNOON
BUT MORE LIKELY WED EVENING. SOUNDINGS SHOW DEVELOPMENT OF MID LEVEL
STABLE LAYER AS SUBSIDENCE DEVELOPS BEHIND EXITING 5H TROUGH AXIS.
AS A RESULT PRECIPITABLE WATER VALUES ARE FORECAST TO DROP UNDER 1.5
INCH BY EVENING LIMITING PRECIP COVERAGE TO EARLIER IN THE DAY.
STILL HOLDING ONTO CHC POP BUT FURTHER REDUCTION MAY BE REQUIRED.

ALTHOUGH THERE WILL BE DRY AIR IN THE MID LEVELS WED INTO THU THE
HIGH BUILDING IN FROM THE NORTH WILL RESULT IN LOW LEVEL NORTH TO
NORTHEAST FLOW. LOW LEVEL MOISTURE UNDER MID LEVEL INVERSION COULD
TRANSLATE TO INCREASED CLOUD COVER WED AND EARLY THU.

LOW LEVEL FLOW BECOMES EAST AND POSSIBLY SOUTHEAST THU INTO THU
NIGHT. AT THE SAME TIME FLOW ALOFT VEERS TO NORTH-NORTHEAST IN
RESPONSE TO WEAK 5H RIDGE BUILDING OVER THE CENTRAL US. THIS HELPS
WEAKEN THE CAP WHICH MAY ALLOW FOR SOME ISOLATED CONVECTION BUT MID
LEVEL DRY AIR REMAINS A BIG OBSTACLE. WILL CARRY SLIGHT CHC POP THU
AFTERNOON BUT THIS MAY BE GENEROUS. LOSS OF HEATING SHOULD END
ANY PRECIP THREAT SO WILL CARRY NO MENTIONABLE POP THU NIGHT.
TEMPERATURES WILL BE NEAR TO SLIGHTLY BELOW CLIMO THROUGH THE
PERIOD.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 3 AM TUESDAY...MID LEVEL RIDGING SHIFTS EAST DURING THE
PERIOD WHILE AT THE SURFACE ELONGATED HIGH MOVES SOUTH OF NEW
ENGLAND. SUBSIDENCE UNDER THE BUILDING RIDGE MAINTAINS DEEP DRY
AIR OVER THE CAROLINAS. FORECAST SOUNDINGS SHOW PWATS DROPPING
UNDER 1 INCH FRI MORNING AND REMAINING UNDER 1 INCH THROUGH THE
WEEKEND. ALTHOUGH THERE WILL BE A SEA BREEZE EACH AFTERNOON THINK
VERY LITTLE IF ANY CU WILL DEVELOP WITH PRECIP CHANCES BEING QUITE
LIMITED. LOW LEVEL AND UPPER LEVEL MOISTURE STARTS TO INCREASE ON
MON AS SURFACE HIGH SHIFTS TO THE MORE TYPICAL BERMUDA LOCATION
AND MID LEVEL RIDGE AXIS CONSOLIDATES OFF THE SOUTHEAST COAST.
INCREASE IN MOISTURE IS NOT ENOUGH TO WARRANT ANYTHING OTHER THAN
A SILENT POP BUT IS LIKELY TO RESULT IN AN INCREASE IN HIGH CLOUD
AS THE PERIOD ENDS. TEMPERATURES START OUT NEAR TO SLIGHTLY BELOW
CLIMO BUT STEADILY INCREASE THROUGH THE PERIOD AS MID LEVEL
RIDGING MOVES OVERHEAD AND SUBSIDENCE INCREASES.

&&

.AVIATION /07Z TUESDAY THROUGH SATURDAY/...
AS OF 06Z...PCPN COVERAGE ACROSS THE CWA HAS DIMINISHED TONIGHT
THOUGH THERE STILL REMAINS A POSSIBILITY OF SCATTERED SHOWERS AND
ISOLATED THUNDERSTORMS.  THEY ARE MOST PROBABLE AT THE COASTAL
TERMINALS FOR THE NEXT TWO OR THREE HOURS.  THE HEAVIER SHOWERS
THIS EVENING OVER THE INLAND TERMS HAVE SATURATED THE SFC LAYER...
AND MVFR/TEMPO IFR CIGS/VSBYS APPEAR LIKELY AT KFLO AND KLBT. NEAR
SFC WINDS ALONG THE COAST SHOULD PRECLUDE FOG...BUT TEMPO MVFR CIGS
ARE POSSIBLE BEFORE DAWN. EXPECT MORE SHOWERS/T-STORMS TODAY AS AN
UPPER TROUGH NEARS THE CAROLINAS. CONFIDENCE IN TIMING AND COVERAGE
IS SOMEWHAT LOW...BUT ANTICIPATE SHOWERS WILL FIRST DEVELOP ALONG
THE SEA BREEZE NEAR THE COAST AND THEN SPREAD INLAND. MAINLY VFR
CONDITIONS SHOULD PREVAIL WITH TEMPO MVFR/IFR IN HEAVIER SHOWERS.
HAVE INCLUDED VCSH FOR ALL TERMS AFTER 00Z AS THE COLD FRONT MOVES
TOWARDS OUR CWA.

EXTENDED OUTLOOK...SHOWERS AND T-STORMS WITH TEMPO MVFR/IFR ON
WEDNESDAY. VFR DEVELOPING THURSDAY SHOULD PERSIST THRU THE EXTENDED
PERIOD.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 3 AM TUESDAY...EXPECT S TO SW WINDS OF 10 TO 15 KT TODAY TO
INCREASE TO 15 TO 20 KT TONIGHT BEFORE DIMINISHING SLIGHTLY LATE AS
THE FRONT NEARS THE WATERS.  SEAS OF 2 TO 3 FT EARLY TODAY WILL PEAK
IN THE 3 TO 5 FT RANGE THIS EVENING BEFORE SUBSIDING SLIGHTLY TOWARD
DAY BREAK.

SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 AM TUESDAY...COLD FRONT PUSHES EAST OF THE WATERS DURING
WED AS HIGH PRESSURE BUILDS IN FROM THEN NORTH. AS A RESULT LIGHT
OFFSHORE FLOW WILL VEER TO NORTH-NORTHEAST WED NIGHT INTO THU.
GRADIENT INCREASES THU AS THE HIGH BUILDS SOUTH...PUSHING
NORTHEAST FLOW AS HIGH TO 15 KT LATER THU AND THU NIGHT. OFFSHORE
FLOW WILL KNOCK SEAS FROM 3 TO 5 FT AT THE START OF THE PERIOD TO
2 TO 3 FT BY THU MORNING. INCREASE IN NORTHEAST FLOW THU AND THU
NIGHT WILL RESULT IN A MARGINAL INCREASE IN SEAS FOR THE SECOND
HALF OF THE PERIOD...3 TO 4 FT.

LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 3 AM TUESDAY...HIGH PRESSURE NORTH OF THE WATERS WILL
REMAIN THE DOMINANT FEATURE THROUGH THE PERIOD. LACK OF GRADIENT
WILL KEEP SPEEDS UNDER 15 KT AND ALLOW FOR DAILY SEA BREEZE WITH
MORE OF AN ONSHORE WIND COMPONENT DEVELOPING NEAR SHORE. SEAS WILL
RUN 2 TO 4 FT THROUGH THE PERIOD.

&&

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

&&

$$

NEAR TERM...31
SHORT TERM...III
LONG TERM...III
AVIATION...BJR/31