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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KLWX 141006
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
606 AM EDT FRI JUN 14 2013

.SYNOPSIS...
AN UPPER LEVEL TROUGH WILL MOVE EAST FROM THE AREA THIS MORNING.
HIGH PRESSURE WILL BUILD OVER THE MID-ATLANTIC THROUGH TONIGHT
BEFORE SHIFTING OFF THE SOUTHEASTERN STATES COAST SATURDAY NIGHT. A
COLD FRONT WILL DRIFT SOUTH OVER THE EAST-CENTRAL STATES SUNDAY
NIGHT THROUGH TUESDAY BEFORE HIGH PRESSURE SHIFTS EAST ACROSS THE
NORTHERN MID-ATLANTIC.

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
CURRENT ANALYSIS SHOWS AND UPPER-LEVEL TROUGH OVERHEAD EARLY THIS
MORNING WHILE SURFACE HIGH PRESSURE BUILDS ACROSS THE GREAT LAKES.
THE STORM SYSTEM THAT AFFECTED OUR REGION THURSDAY CONTINUES TO MOVE
OFF THE NEW ENGLAND COAST.

THE UPPER-LEVEL TROUGH WILL SLOWLY MOVE OFF TO THE EAST TODAY WHILE
THE SURFACE HIGH BUILDS INTO THE OHIO VALLEY. A NORTHWEST FLOW AHEAD
OF THE HIGH WILL USHER IN UNSEASONABLY COOL CONDITIONS FOR THIS TIME
OF YEAR ALONG WITH LOW HUMIDITY. MAX TEMPS WILL RANGE FROM THE 60S
IN THE MOUNTAINS TO THE UPPER 70S/NEAR 80 IN THE WASHINGTON AND
BALTIMORE METROPOLITAN AREAS.

THERE WILL BE LIMITED INSTABILITY DUE TO COLDER AIR ALOFT ASSOCIATED
WITH THE TROUGH. THEREFORE A BROKEN CU DECK IS EXPECTED ALONG WITH A
FEW SPRINKLES. A FEW SHOWERS CANNOT BE RULED OUT...ESPECIALLY
ACROSS NORTHEASTERN MARYLAND AND ALONG THE ALLEGHENY HIGHLANDS.

SURFACE HIGH PRESSURE WILL BUILD OVERHEAD TONIGHT...BRINGING DRY AND
COOL CONDITIONS. MIN TEMPS WILL RANGE FROM THE 40S IN PORTIONS OF
THE ALLEGHENY HIGHLANDS TO THE LOWER AND MIDDLE 60S IN DOWNTOWN
WASHINGTON AND BALTIMORE.
-- End Changed Discussion --

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY/...
SATURDAY...SFC HIGH SHIFTS SOUTHEAST ACROSS THE SRN APPALACHIANS
THROUGH THE DAY. MOSTLY SUNNY WITH JUST A FEW HIGH CLOUDS AND LATE
AFTERNOON FAIR CU NEAR THE BAY. MAX TEMPS JUST BELOW NORMAL IN THE
LOW 80S.

SATURDAY NIGHT...SFC HIGH MOVES OFF THE CAROLINA COAST EN ROUTE TO A
BERMUDA HIGH. A FRONTAL BOUNDARY/BROAD AREA OF CONVERGENCE BETWEEN
THE SUBTROPICAL FLOW AND LOW PRESSURE NEAR THE GREAT LAKES DEVELOPS
OVER THE MIDWEST WHERE THUNDERSTORMS CAN BE EXPECTED. SLY FLOW
CONTINUES A WARMING TREND WITH MIN TEMPS NEAR NORMAL.

SUNDAY...CONVERGENCE ZONE/COLD FRONT SAGS SOUTH INTO THE AREA WITH
LIKELY AFTERNOON THUNDERSTORMS BLUE RIDGE AND WEST... SCATTERED
COVERAGE EAST. MAX TEMPS MID TO UPR 80S WITH THE BERMUDA HIGH IN
PLACE.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
CONVERGENCE ZONE AND ASSOCIATED PRECIP PERSISTS ACROSS THE AREA INTO
MONDAY NIGHT UNTIL LOW PRESSURE OVER THE GREAT LAKES FINALLY PUSHES
THE COLD FRONT INTO THE SRN MID-ATLANTIC. DIURNALLY DRIVEN PRECIP
AND INTENSITY OF THUNDERSTORMS THROUGH THIS TIME. NEAR NORMAL MAX
TEMPS DUE TO CLOUD COVER...AND ABOVE NORMAL MIN TEMPS FOR THE SAME
REASON.

ANOTHER ROUND OF SFC HIGH PRESSURE TUESDAY THROUGH THURSDAY WITH A
RETURN OF SLIGHTLY BELOW NORMAL TEMPERATURES AND DRY CONDITIONS.

&&

.AVIATION /10Z FRIDAY THROUGH TUESDAY/...
NORTHWEST WINDS WILL CONTINUE AHEAD OF HIGH PRESSURE APPROACHING
FROM THE NORTHWEST. GUSTS AROUND 20 TO 25 KNOTS WILL CONTINUE
THROUGH MIDDAY BEFORE WINDS DIMINISH TOWARD EVENING. WINDS WILL BE
LIGHT TONIGHT. PATCHY BR MAY CAUSE BRIEF PERIODS OF MVFR VSBYS
LATE.

VFR SATURDAY INTO SUNDAY AS HIGH PRESSURE MOVES SOUTHEAST ACROSS THE
SOUTHERN MID-ATLANTIC WITH NWLY FLOW AROUND 10 KT SATURDAY BECOMING
5-10 KT SLY FLOW SATURDAY NIGHT. THUNDERSTORMS AHEAD OF A WEAK COLD
FRONT SPREAD ACROSS THE TERMINALS SUNDAY WITH AN ACTIVE PERIOD THEN
THROUGH MONDAY NIGHT WITH DIURNALLY DRIVEN CONVECTIVE STORMS.

&&

.MARINE...
THE PRESSURE GRADIENT WILL GRADUALLY WEAKEN THROUGH TODAY AS HIGH
PRESSURE APPROACHES FROM THE NORTHWEST. THE GALE WARNING HAS BEEN
CANCELLED...BUT A SMALL CRAFT ADVISORY IS IN EFFECT THROUGH THIS
AFTERNOON. WINDS SHOULD REMAIN BELOW SCA CRITERIA TONIGHT.

NWLY FLOW 10 TO 15 KT SATURDAY BECOMES SLY SATURDAY NIGHT.
CHANNELING LATE LOOKS TO GUST AROUND 20 KT INTO SUNDAY. SCA LIKELY.
ACTIVE WEATHER SUNDAY EVENING THROUGH MONDAY NIGHT AS A COLD FRONT
SAGS THROUGH THE AREA.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR
     ANZ530>543.
-- End Changed Discussion --

&&

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