Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000
FXUS61 KPHI 191413
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1013 AM EDT FRI SEP 19 2014

.SYNOPSIS...
HIGH PRESSURE WILL SLIDE ACROSS TO THE NORTH OF THE REGION TODAY AND
THEN SHIFTS OFFSHORE TONIGHT. A COLD FRONT WILL CROSS THE AREA
SUNDAY NIGHT INTO MONDAY. HIGH PRESSURE BUILDS IN FROM THE WEST
MONDAY AND PERSISTS THROUGH THE END OF THE WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
13Z SURFACE ANALYSIS SHOWS A 1031 MB SFC HIGH CENTERED JUST NORTH OF
MONTREAL. HIGH PRESSURE CONTINUES TO NOSE DOWN THE EASTERN SEABOARD,
RESULTING IN A COOL NORTHEAST BREEZE THIS MORNING. THIS HIGH WILL
SHIFT SOUTHEASTWARD TODAY. LOW-LEVEL WINDS AROUND THE HIGH WILL VEER
THROUGHOUT THE DAY AS THE HIGH BUILDS TOWARD THE GULF OF MAINE THIS
AFTERNOON.

THE DEVELOPMENT OF STRATOCU CAN ALREADY BE SEEN NEAR THE NJ (AND TO
A LESSER EXTENT THE DE COAST) ON THE MID MORNING VISIBLE SATELLITE,
WHICH IS A PROXY FOR WHERE THE MARINE LAYER HAS BECOME ESTABLISHED
AND FOR THE LEADING EDGE OF THE STRONGER ONSHORE FLOW. BASED ON
LATEST VISIBLE SATELLITE IMAGERY AND RAP GUIDANCE (WHICH HAS
INITIALIZED WELL WITH LOW-LEVEL RH FIELD), MARINE-LAYER STRATOCU
EXPECTED TO ADVECT INLAND AS FAR WEST AS EASTERN PA TODAY. MIXING
SHOULD BE DEEP ENOUGH ON LAND TO SEE SOME BREAKS IN THE CLOUDS THIS
AFTERNOON AWAY FROM THE COAST.

RETURN FLOW DEVELOPING AROUND THE WESTERN PERIPHERY OF THE RIDGE
WILL PRODUCE WEAK ISENTROPIC LIFT OVER THE CWA LATE THIS AFTERNOON.
KEPT MEASURABLE PRECIP OUT OF THE FORECAST, BUT ADDED IN SPRINKLES
FOR EXTREME SOUTHERN NJ AND THE DELMARVA. THIS PORTION OF THE AREA
SHOULD BE LOCATED CLOSER TO THE GREATER LIFT AND MOISTURE RETURN.

MADE MINOR ADJUSTMENTS TO TEMP FORECAST BASED ON SKY COVER UPDATES.
MAX TEMPS RANGE FROM THE MID/UPPER 60S IN THE HIGHER ELEVATIONS AND
ALONG THE CENTRAL NJ COAST TO LOW/MID 70S SOUTHEAST PA AND THE
DELMARVA.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
THE PERIOD BEGINS AND ENDS WITH AN ONSHORE FLOW. MODELS, INCLUDING
STAT GUIDANCE, HAVE CLOUDS ON THE INCREASE OVERNIGHT. THIS LOOKS
REASONABLE. IN RESPONSE TO THE DEEPENING LOW LEVEL MOISTURE, SOME
DRIZZLE IS POSSIBLE ACROSS OUR UPSLOPE ZONES WEST OF THE DELAWARE
VALLEY AND LOCALES ALONG THE COAST.

OVERNIGHT LOWS WILL DROP INTO THE UPPER 40S ACROSS OUT NORTHWEST
ZONES AND INTO THE MID TO UPPER 50S ACROSS THE COASTAL PLAIN.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
SATURDAY...SATURDAY LOOKS TO BE A PRETTY DRY DAY ACROSS THE REGION.
ALTHOUGH THERE WILL BE A MID LEVEL SHORTWAVE ROTATING THROUGH, THERE
IS NOT AN ABUNDANCE OF MOISTURE AROUND AND IT DOESN`T LOOK LIKE WE
WILL SEE MUCH IN THE WAY OF SHOWERS ACROSS THE AREA.

RETURN FLOW AROUND THE DEPARTING HIGH PRESSURE WILL HELP TO BRING IN
SOME MOISTER AND WARMER AIR. MAX TEMPS WILL RISE INTO THE MID TO
UPPER 70S ACROSS MUCH OF THE REGION. TEMPS OVERNIGHT WILL DROP INTO
THE UPPER 50S TO LOWER 60S.

SUNDAY...A COLD FRONT WILL GRADUALLY PUSH TOWARDS THE REGION ON
SUNDAY. HOWEVER, THE FRONTS PROGRESS APPEARS TO BE ON THE SLOW SIDE
AND IT LIKELY WONT REACH THE REGION UNTIL LATER IN THE DAY AND WON`T
FULLY MOVE OFFSHORE UNTIL LATE SUNDAY NIGHT/EARLY MONDAY MORNING. WE
HAVE ADDED A SLIGHT CHANCE OF THUNDER INTO THE FORECAST FOR SUNDAY
AFTERNOON/NIGHT. THE INSTABILITY ISN`T TERRIBLY STRONG BUT IT IS
AVAILABLE AND WE CAN`T RULE OUT A RUMBLE OR TWO ACROSS THE REGION.
BEST CHANCES LOOK TO BE OUT AHEAD OF THE FRONT AND CHANCES WILL
DIMINISH AS WE HEAD INTO SUNDAY NIGHT.

SUNDAY WILL BE THE WARMEST DAY OF THE WEEK ACROSS OUR AREA AS MAX
TEMPS REACH INTO THE 80S. BEHIND THE FRONT, TEMPERATURES WILL DROP
AND OVERNIGHT LOWS WILL DROP INTO THE 50S. WHERE SKIES START TO
CLEAR A BIT MORE, ESPECIALLY ACROSS THE NORTHWESTERN AREAS, WE COULD
SEE TEMPS DROP DOWN INTO THE UPPER 40S.

MONDAY...THE COLD FRONT PUSHES TO THE SOUTH OF THE AREA AND WE
SHOULD SEE SOME DRIER AND COOLER AIR MOVING IN ON THE NORTHWEST
FLOW. ANY LINGERING SHOWERS WILL CLEAR QUICKLY. MAX TEMPS WILL BE
AROUND 8-12 DEGREES COOLER ACROSS THE REGION. MOST AREAS WILL SEE
MAX TEMPS IN THE UPPER 60S TO LOWER 70S. OVERNIGHT LOWS WILL FEEL
CONSIDERABLY COLDER, WITH MOST PLACE DROPPING DOWN INTO THE 40S,
WITH SOME 50S POSSIBLE CLOSER TO THE COAST.

TUESDAY THRU THURSDAY...HIGH PRESSURE STARTS TO BUILD IN FROM THE
WEST ON TUESDAY. THE HIGH GRADUALLY SHIFTS TO THE NORTH OF THE
REGION AND SLOWLY MOVES ACROSS AND INTO NEW ENGLAND THROUGH THE
WEEK. THIS WILL KEEP THE WEATHER PRETTY DRY WITH A SOUTH TO
SOUTHEAST FLOW ACROSS THE REGION. A MID LEVEL SHORTWAVE WILL ROTATE
THROUGH THE AREA ON TUESDAY AND MAY SPARK OFF A FEW SHOWERS. FOR
NOW, WE HAVE KEPT THE FORECAST DRY AS THE SOUNDINGS LOOK PRETTY
DRY.

&&

.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

NORTHEAST WINDS THIS MORNING 10-15 KT WILL OCCASIONALLY GUST NEAR 20
KT FROM THE PHILLY TERMINALS SOUTH AND EAST. GRADIENT FLOW WEAKENS A
BIT THIS AFTN AS WINDS VEER OUT OF THE EAST. MARINE AIRMASS WILL
MOVE INLAND AS WELL WITH A PERIOD OF MVFR CIGS POSSIBLE. NEEDED TO
UPDATE 12Z TAFS FOR A FEW LOCATIONS AS STRATOCU HAS DEVELOPED SOONER
THAN PREVIOUSLY FORECAST. EXPECT IMPROVEMENT TO VFR DURING THE AFTN
AT ALL TERMINALS EXCEPT ACY, WHERE MARINE AIR IS MORE ESTABLISHED.

TONIGHT...WITH THE ONSHORE FLOW, LOWERING AND THICKENING CLOUDS CAN
BE EXPECTED. FOR NOW WE`LL DROP THINGS DOWN TO MVFR, 1500-2500 FT.
SOME DRIZZLE IS POSSIBLE, ESPECIALLY ACROSS KABE, KRDG, KACY, AND
KMIV. WINDS WILL REMAIN OUT OF THE EAST, BUT LIGHTEN UP A BIT.

OUTLOOK...
SATURDAY THROUGH SATURDAY NIGHT...MAINLY VFR CONDITIONS EXPECTED.
STRATUS/FOG DEVELOPMENT POSSIBLE SATURDAY NIGHT WITH LOWER CEILINGS
AND VISIBILITIES INTO SUNDAY MORNING.

SUNDAY THROUGH SUNDAY NIGHT...FOG/STRATUS POSSIBLE EARLY...THEN
MAINLY VFR CONDITIONS EXPECTED MUCH OF THE DAY. LOWER VISIBILITIES
AND CEILINGS POSSIBLE THROUGH THE AFTERNOON/EVENING IN
SHOWERS/THUNDERSTORMS IN ADVANCE OF AN APPROACHING COLD FRONT. THE
FRONT WILL MOVE THROUGH LATE SUNDAY INTO MONDAY.

MONDAY THROUGH TUESDAY...MAINLY VFR CONDITIONS EXPECTED. NORTHWEST
WINDS AROUND 10 TO 15 KNOTS ON MONDAY...LESS WINDY ON TUESDAY.

&&

.MARINE...
BOTH BUOY 44065 AND 44025 ARE FINALLY BACK IN SERVICE!

NORTHEAST WIND SURGE HAS ADVANCED SOUTHWARD ALONG THE COAST THIS
MORNING, REACHING ATLANTIC CITY BY 10 AM WITH GUSTS AROUND 25 KT.
HAVE EXPANDED SCA TO INCLUDE LITTLE EGG INLET TO GREAT EGG
INLET. SCA ALREADY IN EFFECT TODAY FOR MARINE ZONES FARTHER
NORTH. WINDS WILL LIKELY SUBSIDE A BIT TO BELOW SCA THRESHOLD
DURING THE AFTN BUT SEAS BUILDING TO 5 FT WILL RESULT IN A
CONTINUATION OF SCA CONDITIONS THRU THE REMAINDER OF THE DAY.

TONIGHT...ALSO MADE SOME CHANGES TO THE GRIDS. WE`VE BACKED OFF OF
HEADLINES AND HAVE DELAYED THE SCA FOR THE SOUTHERN WATERS. ACROSS
THE NORTHERN WATERS, WE`LL HAVE THE SCA RUN THROUGH ABOUT 06Z. LOOKS
LIKE A LOWER END SCA WITH WINDS TOPPING OUT AROUND 20 KT AND SEAS 5
FT.

OUTLOOK...
SATURDAY...SEAS LOOK TO BE ELEVATED HEADING THROUGH
THE DAY ON SATURDAY AND WILL GRADUALLY START TO SUBSIDE INTO
SATURDAY EVENING. THE SMALL CRAFT ADVISORY HAS BEEN EXTENDED
THROUGH LATE SATURDAY AFTERNOON AT THIS TIME. IT MAY NEED TO BE
EXTENDED INTO SATURDAY EVENING FOR A PERIOD UNTIL SEAS FALL BELOW
5 FEET. WINDS LOOK TO REMAIN BELOW 25 KNOTS ACROSS THE WATERS.

SUNDAY...WINDS AND WAVES ARE EXPECTED TO REMAIN BELOW ADVISORY
CRITERIA THROUGH SUNDAY.

SUNDAY NIGHT THROUGH MONDAY...A COLD FRONT WILL CROSS THE AREA
WATERS LATE SUNDAY INTO EARLY MONDAY. SHOWERS AND THUNDERSTORMS WILL
ACCOMPANY THE FRONTAL PASSAGE. IN ADDITION, WINDS AND WAVES WILL
START TO INCREASE AND A SMALL CRAFT ADVISORY MAY BE NEEDED.

TUESDAY...SUB-ADVISORY CONDITIONS ARE EXPECTED AS HIGH PRESSURE
MOVES INTO THE REGION.

&&

.RIP CURRENTS...
WITH LONG PERIOD SWELLS STILL PRESENT TODAY, A TIGHTENING GRADIENT
AND INCREASING WAVE HEIGHTS, IN HOUSE GUIDANCE CONTINUES TO SUGGEST
A MODERATE RISK TODAY FOR NJ AND DE.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR ANZ452.
     SMALL CRAFT ADVISORY FROM 2 AM TO 6 PM EDT SATURDAY FOR
     ANZ453>455.
     SMALL CRAFT ADVISORY UNTIL 2 AM EDT SATURDAY FOR ANZ450-451.

&&

$$
SYNOPSIS...MEOLA
NEAR TERM...KLEIN
SHORT TERM...KRUZDLO
LONG TERM...MEOLA
AVIATION...KLEIN/KRUZDLO/MEOLA
MARINE...KLEIN/KRUZDLO/MEOLA
RIP CURRENTS...KRUZDLO




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