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000
FXUS61 KPHI 151755
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
155 PM EDT SAT JUN 15 2013

.SYNOPSIS...
HIGH PRESSURE OVER THE REGION TODAY WILL MOVE OFF THE EAST COAST
TONIGHT ALLOWING A RETURN TO MORE TYPICAL SUMMERTIME SOUTHWEST
WINDS FOR SUNDAY. LOW PRESSURE MOVING EAST THROUGH THE GREAT LAKES
AND SOUTHEAST CANADA ON SUNDAY AND MONDAY WILL BRING A CHANCE FOR
MAINLY AFTERNOON SHOWERS AND THUNDERSTORMS. SHOWERS AND
THUNDERSTORMS WILL ALSO ACCOMPANY THE PASSAGE OF A COLD FRONT ON
TUESDAY...FOLLOWED BY HIGH PRESSURE AND FAIR WEATHER FOR THE
MIDDLE AND LATTER PART OF NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
GRIDS ARE IN GOOD SHAPE. JUST MADE A FEW TWEAKS TO THE HOURLY
TEMPERATURES AS THEY ARE SLIGHTLY WARMER GIVEN THE SUNSHINE AND
WEAK (FOR THE TIME BEING) WESTERLY FLOW.

OTHERWISE, HIGH PRESSURE WILL SLIDE TO OUR SOUTH AND EAST THROUGH
THE DAY TODAY. THE WINDS WILL SHIFT FROM THE NORTHWEST TO THE
SOUTHWEST THIS AFTERNOON AND GENERALLY BE AROUND 10 TO 15 MPH.

SKIES WILL BE MOSTLY SUNNY AND WITH JUST ENOUGH LOW LEVEL MOISTURE
AROUND, SOME CUMULUS MAY DEVELOP AS THE SURFACE HEATS UP. NO
PRECIPITATION IS EXPECTED AND WE WILL SEE A NICE DRY DAY ACROSS THE
REGION.

TEMPERATURES WILL BE WARMER TODAY THAN THEY WERE ON FRIDAY AND WE
SHOULD BE BACK NEAR NORMAL ACROSS THE REGION. HIGHS IN THE LOWER 80S
ACROSS THE AREA WITH SOME COOLER TEMPERATURES ACROSS THE NORTH AND
ALONG THE COAST.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/...
THE CUMULUS WILL START TO DISSIPATE TONIGHT AS WE LOSE OUT
SURFACE HEATING. HOWEVER, AS THE NEXT SYSTEM STARTS TO APPROACH
FROM THE WEST, WE WILL SEE AN INCREASE IN OVERALL CLOUDINESS BY
LATE TONIGHT.

OTHERWISE, IT WILL BE DRY TONIGHT WITH OVERNIGHT TEMPERATURES
GENERALLY IN THE UPPER 50S TO LOWER 60S.

&&

.LONG TERM /SUNDAY THROUGH SATURDAY/...
BY SUNDAY MORNING A MORE TYPICAL SUMMERTIME BERMUDA HIGH PATTERN
WILL BE RE-ESTABLISHED ALONG THE EAST COAST WITH SWLY LOW LVL
FLOW AND ASSOCD INCREASING HUMIDITY. FCST FLOW ALOFT IS MAINLY
ZONAL BUT A SHRTWV TROF IS INDICATED MOVING BY TO OUR NORTH.
ASSOCD UVV AND INCREASING MOISTURE/INSTBY WILL TRIGGER SOME
AFTERNOON SHOWERS/T-STORMS ACROSS THE AREA ON SUNDAY.

ON MONDAY THERE SEEMS TO BE LESS FORCING FOR UVV ALOFT BUT THE AMS
IS SIMILAR...MAYBE EVEN A LITTLE HIGHER SFC THETA-E...AND SOME
TROFINESS AT THE SFC SO SOME AFTN CONVECT ON CANNOT BE RULED OUT
AND WE HAVE KEPT SLGT CHC TO CHC POPS IN THE FCST.

ON MONDAY NIGHT AND TUESDAY A COLD FRONT WILL BE APPROACHING FROM
THE NW AND SHOULD MOVE THROUGH SOMETIME DURING THE DAY ON TUESDAY.
WARM ADVECTION AND LOW LVL CONVERGENCE AHEAD OF THE FRONT SHOULD
BE ENOUGH TO TRIGGER SHOWERS AND THUNDERSTORMS.

BY WEDNESDAY THE FRONT HAS MOVED THROUGH FOLLOWED BY HIGH PRESSURE
AND A COOLER AND DRIER AIR MASS. BY THE END OF THE WEEK THE HIGH
PRESSURE MOVES OFFSHORE BRINGING A RETURN SLY FLOW AND A LEAST A
CLIMO CHC FOR AFTN CONVECTION.

NOTE...THE 00Z GFS RUN SEEMS TO BE AFFECTED BY CONVECTIVE FEEDBACK
RESULTING IN AN UNSEASONABLY STRONG LOW MOVING THROUGH THE MID-
ATLANTIC AREA ON WEDNESDAY. THIS FEATURE WAS DISCOUNTED.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
VFR CONDITIONS WILL PREVAIL AT THE TERMINALS THROUGH THE TAF PERIOD.

THIS EVENING - TONIGHT...VFR WITH A LIGHT SOUTHWESTERLY WIND. ANY
GUSTINESS WILL DROP OFF WITHIN THE NEXT COUPLE OF HOURS AS THE
PRESSURE GRADIENT WEAKENS AND DEEPER MIXING SHUTS OFF.

SUNDAY...VFR. INCREASING MID-LEVEL CLOUDS FROM THE WEST WITH AN
INCREASE IN LOW-LEVEL MOISTURE EXPECTED. A WEAK SURFACE TROUGH WILL NEAR
LATER IN THE AFTERNOON AND MAY TOUCH OFF A FEW SHOWERS WITH POSSIBLY
A THUNDERSTORM...COULD PRODUCE LOCAL MVFR CONDITIONS. THESE WERE NOT ADDED
TO THE TAF GIVEN THE SPATIAL COVERAGE UNCERTAINTY AND INITIATION
TIMING. DEEPER MIXING, UNDER SOUTHWESTERLY FLOW, SURFACE AND
ALOFT, MAY YIELD SOME GUSTINESS IN THE LOW 20 KNOTS RANGE.

OUTLOOK...
SUNDAY NIGHT - MONDAY NIGHT...MOSTLY VFR CONDS WITH SW WINDS 5 TO 10
KT. SOME MVFR CONDS POSSIBLE IN SCATTERED
SHWRS/T-STORMS...ESPECIALLY DURING THE AFTN AND EVENING MONDAY.

TUESDAY...GENERALLY VFR CONDITIONS BUT MVFR OR LOWER IN SHWRS AND
T-STORMS DURING THE DAY. SW WINDS AROUND 10 KT.

WEDNESDAY...VFR CONDITIONS EXPECTED WITH LIGHT NW TO N WINDS.

&&

.MARINE...
SEAS HAVE FALLEN BELOW 5 FEET AT BUOY 44009 AND WE HAVE CANCELLED
THE SMALL CRAFT ADVISORY.

OTHERWISE, SUB-ADVISORY CONDITIONS WILL PREVAIL THROUGH TODAY AND
CONTINUE OVERNIGHT. WITH HIGH PRESSURE SLIDING TO OUR SOUTH AND EAST
THROUGH THE DAY, WINDS WILL START OUT OF THE NORTHWEST BUT WILL
BECOME SOUTHWESTERLY THIS AFTERNOON. WIND SPEEDS WILL BE AROUND 10
TO 15 KNOTS ACROSS THE AREA WATERS WITH SEAS AROUND 2 TO 4 FEET ON
THE OCEAN.


OUTLOOK...FOR THE PERIOD SATURDAY THROUGH WEDNESDAY...NO SCA
CONDITIONS ARE EXPECTED AT THIS TIME...ALTHOUGH SW WINDS ON SUNDAY
COULD BE SOMEWHAT GUSTY. SW WINDS ON SUNDAY AND MONDAY WILL SHIFT
TO NW LATER ON TUESDAY WITH A COLD FRONTAL PASSAGE. SCATTERED
SHOWERS/T-STORMS ARE POSSIBLE ON SUNDAY AND MONDAY BUT MORE LIKELY
ON TUESDAY.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...AMC
NEAR TERM...HEAVENER/MEOLA
SHORT TERM...MEOLA
LONG TERM...AMC
AVIATION...AMC/HEAVENER
MARINE...AMC/MEOLA