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000
FXUS61 KLWX 160808
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
408 AM EDT SUN JUN 16 2013

.SYNOPSIS...
HIGH PRESSURE WILL MOVE OFF THE CAROLINA COAST TODAY AS A SURFACE
TROUGH APPROACHES THIS AFTERNOON. A WEAK COLD FRONT WILL APPROACH
FROM THE NORTH ON MONDAY...BECOMING STATIONARY ALONG THE MASON DIXON
LINE THROUGH TUESDAY. MEANWHILE AN AREA OF LOW PRESSURE WILL PASS
SOUTH OF THE AREA TUESDAY. HIGH PRESSURE THEN RETURNS FOR THE REST
OF THE WEEK INTO THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 07Z...1021MB SFC HIGH PRESSURE OFF NC COAST WITH A WEAK SFC
TROUGH OVER THE UPR MIDWEST. FURTHERMORE...TWO WEAK SHORTWAVES ARE
APPARENT FROM REGIONAL RADAR...ONE OVER CENTRAL PA AND ANOTHER OVER
IL. LIGHT SHOWERS WILL CONTINUE TO PUSH EAST ALONG AND NORTH OF THE
MASON-DIXON LINE...WITH MID-LEVEL CLOUDS SOUTH...THROUGH THE
MID-MORNING HOURS.

TODAY...THE SFC HIGH WILL CONTINUE TO MOVE EAST FROM THE CAROLINA
COAST AS A SFC TROUGH CROSSES THE CENTRAL MID-ATLANTIC FROM THE WEST
THIS AFTERNOON. SINCE THE FORCING SHIFTS INTO THE AREA DURING THE
PEAK HEATING OF THE AFTERNOON...A WEST TO EAST PROGRESSION OF LIKELY
POPS WAS MAINTAINED. MODERATE INSTABILITY UNDER A BROAD UPR TROUGH.
SBCAPE OF 1500 TO 2000 J/KG (AS PROGGED BY GFS AND NAM BUFR
SOUNDINGS) WILL ENABLE A GENERAL HAIL AND WIND THREAT AS NOTED BY
SPC.

SWLY FLOW WITH GUSTS TO AROUND 25 MPH THIS AFTERNOON. THIS WILL MIX
THE 14-16C 850MB TEMPS...EXPECT MAX TEMPS MID TO UPR 80S...A FEW
DEGREES ABOVE NORMAL.

THE SFC TROUGH SHOULD SAG SOUTH OF THE CWA BY LATE TONIGHT WITH THE
FOCUS ONGOING ACTIVITY MOVING SOUTH WITH IT. HOWEVER...NAM/GFS BUFR
SOUNDINGS BOTH DEPICT LATE NIGHT ELEVATED INSTABILITY. WITH PLENTY
OF OUTFLOW BOUNDARIES AROUND...WILL RAISE POPS TO CHANCE FOR LATE
TONIGHT. MILD NIGHT WITH MAV/MET/SREF BLEND GIVING MID 60S WEST OF
THE BLUE RIDGE AND UPR 60S EAST WTIH 70F IN URBAN/NEAR SHORE LOCALES.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
LOW PRESSURE OVER THE SRN PLAINS AS SHOWN IN 00Z NCEP GUIDANCE WILL
BRING AN INCREASE IN MOISTURE TO THE MID ATLANTIC ON TUE AS THE LOW
SYSTEM MOVES EAST. DIFFERENCES IN 00Z GFS/NAM ARE APPARENT BEGINNING
FROM 00Z TUE ON...WITH THE 00Z GFS KEEPING SURFACE LOW SYS WILL SOUTH
OF OUR CWA WHILE THE 00Z/NAM IS MUCH FURTHER NORTH WHILE 21Z SREF IS
JUST SOUTH OF THE NAM POSITION WITH THE LOW ON TUE. WILL HEDGE MORE
TO 00Z GFS SOLUTION...WHICH BRINGS LIKELY CHANCES OF PRECIP UP DURING
DAY ON TUE. 00Z/GFS SHOWS GOOD FRONTAL BANDING POTENTIAL FOR
PRECIPITATION ORIENTED EAST-WEST ACROSS THE REGION. HAVE SHADED THE
POP CHANCES FROM N-TO-S FROM CHANCE TO LIKELY. TUE NGT...LOW PRES
MOVES OFF THE CAROLINA COAST AND PRECIP SHOULD END AS IT MOVES OUT.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
SFC HIGH PRESS OF 1020 HPA AS ADVRTZED IN 00Z/GFS WILL HELP TO PUSH
THE FRONT SOUTH OF REGION WED. 00Z MDLS CONSISTENT WITH BOTH GFS AND
ECMWF SHOWING HIGH PRESSURE IN CONTROL REST OF WEEK WITH ONLY SMALL
VARIATIONS IN POSITION OF HIGH. 00Z ECMWF SHOWS SFC WINDS MORE
EASTERLY STARTING ON THU...AS CLOUDS/MOISTURE STAY S WITH FRONTAL
ZONE BY WEEKS END. HIGH PRES EXPECTED TO CONTINUE THROUGH WEEKEND.


&&

.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
VFR CONTINUES INTO TODAY AS HIGH PRESSURE MOVES OFF THE CAROLINA
COAST ALLOWING GUSTY RETURN SWLY FLOW. SCATTERED THUNDERSTORMS AHEAD
OF A WEAK COLD FRONT SPREAD ACROSS THE TERMINALS THIS
AFTERNOON...CONTINUING THROUGH TONIGHT.

ON MON...SCTD TSTMS DURING THE AFTERNOON COULD IMPACT SOME
TERMINALS WITH LOCALLY MVFR CIGS/VSBYS. MORE ORGANIZED AREA OF
MVFR TO IFR CONDITIONS EXPECTED ON TUE AS LOW PRESSURE SLIDES EAST
ACROSS THE CAROLINAS. BY TUE NIGHT PRECIP WILL END...BUT SOME MVFR
VSBYS IN FOG POSSBILE TUE NIGHT. HIGH PRES BUILDS IN ON WED AND
CONTINUES THROUGH THU BRING VFR CONDITIONS BOTH DAYS.

&&

.MARINE...
SWLY FLOW INCREASES TODAY WITH AFTERNOON GUSTS AROUND 25 KT. SCA FOR
ALL WATERS AT 10 AM AND CONTINUES UNTIL 8PM. ACTIVE WEATHER THIS
EVENING THROUGH TONIGHT AS A WEAK COLD FRONT MOVES THROUGH.

WINDS REMAINING BELOW SCA LEVELS FOR MOST OF MON THROUGH THU. A
CHANCE OF SHOWERS AND TSTMS FROM MON AFTERNOON THROUGH TUE NIGHT.
HIGH PRES BUILDS ACROSS THE WATERS ON WED AND CONTINUES THROUGH
THE END OF THE WEEK.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 8 PM EDT THIS
     EVENING FOR ANZ530>533-535-536-538>542.
     SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ534-
     537-543.

&&

$$
SYNOPSIS...BAJ/SMZ
NEAR TERM...BAJ
SHORT TERM...SMZ
LONG TERM...SMZ
AVIATION...BAJ/SMZ
MARINE...BAJ/SMZ