Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000
FXUS61 KPHI 180139
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
939 PM EDT FRI OCT 17 2014

.SYNOPSIS...
A COLD FRONT WILL CROSS THE AREA EARLY SATURDAY WITH HIGH PRESSURE
BUILDING IN OVER THE WEEKEND. THE HIGH PRESSURE WILL THEN SLIDE
ACROSS THE REGION ON MONDAY. A FRONTAL SYSTEM WILL CROSS THE AREA
AROUND TUESDAY WITH ANOTHER SYSTEM DEVELOPING ALONG IT AS IT MOVES
TO OUR EAST. THIS SECOND SYSTEM WILL BE SLOW TO MOVE AWAY AND WILL
IMPACT THE AREA THROUGH AT LEAST THURSDAY BEFORE MOVING WELL TO
OUR NORTH AND EAST. HIGH PRESSURE WILL START TO BUILD IN FOR THE
END OF THE WEEK.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
A VORT MAX CAN BE SEEN DIGGING TOWARD THE BASE OF AN UPPER TROUGH
OVER THE UPPER MIDWEST/GREAT LAKES REGION ON THE WATER VAPOR
SATELLITE LOOP THIS EVE. AT THE SURFACE...A COLD FRONT WAS ANALYZED
OVER THE OH AND TN VALLEYS AT 01Z. THIS FRONT WILL CONTINUE TO
PROGRESS EASTWARD TONIGHT, ENTERING THE WESTERN FRINGE OF THE CWA BY
THE EARLY MORNING.

OBSERVED HOURLY TEMPS AS OF 9 PM ARE A BIT LOWER THAN PREVIOUSLY
FORECAST UNDER CLEAR SKIES AND LIGHT WINDS. DESPITE THE QUICK
INITIAL DROP, DID NOT MAKE BIG ADJUSTMENTS TO MIN TEMPS AS TEMPS NOT
EXPECTED TO DROP AS MUCH LATER TONIGHT WHEN CLOUDS ASSOCIATED WITH
THE UPPER TROUGH SPILLS IN FROM THE WEST. FORECAST MIN TEMPS IN THE
50S WILL BE SLIGHTLY ABOVE NORMAL FOR MID OCTOBER AS RESULT OF
BACKED WINDS OUT OF THE S-SW IN THE PRE-FRONTAL WARM SECTOR.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/...
THE COLD FRONT IS FCST TO MOVE RAPIDLY ACROSS THE AREA SAT MORNING
AND PUSH OFFSHORE BY EARLY AFTN.

LATEST HIRES GUIDANCE, INCLUDING THE HRRR, PROG LIGHT SHOWERS TO
BE ON THE DOORSTEP OF POCONOS TOWARD DAYBREAK. WITH THE H5 VORT
MAX TRACKING NORTH OF THE AREA, CONFINED SLIGHT CHANCE POPS TO THE
FAR NORTHWESTERN ZONES FOR THE MORNING. FORECAST SOUNDINGS SHOW A
DEEP MIXED LAYER WITH STRONG CAA ALOFT. EXPECT TO A GOOD DEAL OF
STRATOCU DURING THE AFTN. ANY SHOWERS WILL BE ISOLATED, LIGHT AND
MAINLY LIMITED TO THE HIGHER ELEVATIONS. OPTED FOR ISOLATED SPRINKLES
FARTHER SOUTH AND EAST TOWARD I-95.

WINDS BEHIND THE FRONT WILL SHIFT TO THE W/WNW AND BECOME RATHER
GUSTY. MAX TEMPS N/W OF PHL WILL BE 5 TO 10 DEG F COOLER THAN TODAY
WITH STRONG COLD ADVECTION...BUT THE LATER TIMING S/E WILL ALLOW
TEMPS TO RISE CLOSE TO TODAYS READINGS BEFORE THE STRONGER COLD
ADVECTION MOVES IN.

&&

.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
MID LEVEL PATTERN...A TROUGH DEEPENS ACROSS THE EASTERN UNITED
STATES WITH SEVERAL WAVES MOVING THROUGH IT THROUGH SUNDAY. THE
TROUGH DIGS DEEP AGAIN EARLY IN THE WEEK AND LOOKS TO CUT OFF AROUND
LATE TUESDAY/EARLY WEDNESDAY. THE CUT OFF LOW WILL BE SLOW TO MOVE
EASTWARD, FINALLY LIFTING NORTHWARD TOWARD THE WEEKEND.

SURFACE PATTERN...HIGH PRESSURE BUILDS OVER THE WEEKEND AND PERSISTS
THROUGH MONDAY. A LOW PRESSURE SYSTEM WILL MOVE INTO THE AREA LATE
MONDAY AND CROSS THE REGION ON TUESDAY. ANOTHER LOW WILL FORM ALONG
THE DEPARTING BOUNDARY AND VERY SLOWLY MOVE NORTHEAST THROUGH
THURSDAY, WHILE REMAINING JUST EAST OF OUR AREA. HIGH PRESSURE WILL
START TO BUILD IN FOR THE END OF THE WEEK.

SATURDAY NIGHT...THE FRONT WILL HAVE MOVED WELL OFFSHORE AND COLD
AIR ADVECTION WILL BRING COOLER AIR TO THE REGION. SOME LINGERING
SHOWERS MAY STILL OCCUR, ESPECIALLY ACROSS THE NORTH AS THE CAA
MOVES IN. THERE MAY BE ENOUGH COLD AIR FOR SOME LIGHT SNOW SHOWERS
TO OCCUR OVER THE HIGHER TERRAIN. TEMPERATURES WILL RESPOND BUT WITH
SOME CLOUDS STILL IN PLACE, IT WONT BE AS COLD AS IT COULD BE AND
THIS, ALONG WITH THE WIND, SHOULD BE ENOUGH TO PREVENT MUCH FROST
FROM FORMING. EXPECT LOWS TO DROP INTO THE 40S WITH SOME 30S ACROSS
THE NORTH.

SUNDAY...HIGH PRESSURE CONTINUES TO BUILD ACROSS TO THE SOUTH OF THE
REGION ON SUNDAY AND THE BASE OF THE MID LEVEL TROUGH WILL ROTATE
THROUGH THE REGION EARLY IN THE DAY. THE TROUGH WILL USHER IN SOME
MUCH COOLER AIR AND WE IT WILL CERTAINLY FEEL MUCH MORE LIKE FALL
THAN IT HAS RECENTLY. CLOUDS WILL CLEAR AND WE SHOULD HAVE PLENTY OF
SUNSHINE, ALTHOUGH IT LOOKS LIKE SOME CLOUDS MAY HANG AROUND THE
NORTHERN AREAS A BIT LONGER. HOWEVER, WITH THE WINDS BLOWING, IT
WILL FEEL A FEW DEGREES COOLER THAN THE TEMPERATURES ACTUALLY ARE.

SUNDAY NIGHT WILL BE THE COLDEST NIGHT OF THE WEEK. MOSTLY CLEAR
SKIES AND DIMINISHING WINDS WILL HELP US TO RADIATE EFFICIENTLY AND
TEMPERATURES WILL CERTAINLY DROP AS A RESULT. THIS COULD BE THE
NIGHT TO END THE GROWING SEASON ACROSS OUR NORTHERN COUNTIES AS
TEMPS DROP INTO THE LOWER 30S. THERE IS A WRENCH IN THERE THOUGH. WE
START TO SEE SOME WAA DEVELOP AND THAT WILL ADD A BIT MORE MOISTURE
TO THE ATMOSPHERE. THE CLOUDS WILL START TO MOVE BACK IN AND MAY
PROHIBIT FROST DEVELOPMENT AS WELL AS KEEP THE TEMPS SLIGHTLY
WARMER.

MONDAY THROUGH FRIDAY...THIS TIME FRAME IS THE CATALYST OF THE
EXTENDED. WITH A CLOSED UPPER LOW DEVELOPING TO THE WEST OF THE AREA
AND THEN MOVING SLOWLY ACROSS THE REGION, THERE WILL BE A LOT OF
UNCERTAINTY AS TO THE TIMING AND LOCATION OF PRECIPITATION. WHAT WE
CAN BE SURE OF IS THAT THIS TYPE OF FEATURE TENDS TO SLOW THINGS
DOWN. THE SURFACE LOW WILL MOVE INTO THE AREA ON MONDAY/TUESDAY AND
THAT IS WHEN WE EXPECT THE FIRST BATCH OF PRECIPITATION TO MOVE
THROUGH OUR AREA. THE SURFACE LOW WILL THEN SLOWLY MOVE TOWARD THE
COAST AND SHOULD BE OFFSHORE BY LATE TUESDAY/WEDNESDAY MORNING. BY
WEDNESDAY MORNING, THE UPPER LOW WILL STARTING TO MOVE THROUGH OUR
AREA. THE SURFACE LOW AND THE UPPER LOW GET CAUGHT UP TOGETHER
WEDNESDAY AFTERNOON-ISH AND ONCE THEY WRAP EACH OTHER UP, THINGS
WILL SLOW A BIT AND WE COULD SEE SOME PRECIPITATION CONTINUE INTO
THURSDAY, ESPECIALLY SINCE WE HAVE A HIGH LOCATED TO NORTH WHICH
WILL PREVENT THIS SYSTEM FROM LIFTING TO THE NORTH SOONER. THE BRISK
NORTHEAST WIND WILL ALSO CAUSE SOME ISSUES ALONG THE COAST,
ESPECIALLY WITH THE NEW MOON EXPECTED ON THURSDAY.

THINGS LOOK TO START CLEARING UP BY FRIDAY BUT IT WILL BE DEPENDENT
ON HOW FAST THE LOWS MOVE AWAY FROM THE REGION. SOME LIGHT SHOWERS
MAY CONTINUE INTO FRIDAY BEFORE WE REALLY CLEAR OUT TOWARD THE
AFTERNOON.

THIS PERIOD WILL BE PUNCTUATED WITH CLOUDINESS AND NEAR TO BELOW
NORMAL TEMPERATURES.

&&

.AVIATION /01Z SATURDAY THROUGH WEDNESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

VFR CONDITIONS TNGT AND SAT. LIGHT S-SW WINDS AOB 10 KT TNGT WILL
BECOME WLY IN WAKE OF COLD FROPA ON SAT. EXPECT BREEZY CONDITIONS
WITH GUSTS UP TO 25 KT DURING THE LATE MRNG AND AFTN.

OUTLOOK...
SATURDAY NIGHT THROUGH SUNDAY...MAINLY VFR CONDITIONS EXPECTED.
GUSTY WEST TO NORTHWEST WINDS EXPECTED WITH GUSTS TO 25 KNOTS,
MAINLY DURING THE DAY ON SUNDAY.

MONDAY...VFR CONDITIONS EXPECTED.

MONDAY NIGHT THROUGH WEDNESDAY...PERIODS OF VFR AND SUB-VFR
CONDITIONS AS SEVERAL SYSTEMS AFFECT THE TERMINALS. ESPECIALLY ON
TUESDAY AND WEDNESDAY.

&&

.MARINE...
SCA REMAINS IN EFFECT FOR ATLANTIC COASTAL WATERS TONIGHT AND SAT
MORNING MAINLY FOR SEAS. SEAS WERE BELOW 5 FT THIS AFTN BUT HAVE
STARTED TO INCREASE TO 5-6 FT THIS EVE AS LONG-PERIOD SWELLS FROM
HURRICANE GONZALO REACH THE EAST COAST. WINDS BECOME GUSTY ON
SATURDAY (20-30 KT), ESPECIALLY DURING THE AFTN BEHIND A COLD FRONT.
THE SCA EXPANDS TO INCLUDE THE DELAWARE BAY EARLY TOMORROW AFTN.

OUTLOOK...
SATURDAY NIGHT THROUGH SUNDAY...THE SMALL CRAFT ADVISORY HAS BEEN
EXTENDED THROUGH SUNDAY AS WINDS AND WAVES WILL BOTH CONTINUE TO
MEET CRITERIA. WINDS WILL CONTINUE TO GUST ABOVE 25 KNOTS ON THE
DELAWARE BAY AS WELL.

SUNDAY AFTERNOON AND NIGHT...THE WINDS WILL START TO DIMINISH AS WE
HEAD THROUGH THE AFTERNOON AND INTO THE EVENING HOURS. FIRST THE
DELAWARE BAY WILL LOSE THE GUSTINESS AND THEN THE OCEAN WATERS. THE
SEAS WILL TAKE A BIT LONGER TO SUBSIDE BUT SHOULD FALL BELOW 5 FEET
SOMETIME SUNDAY NIGHT.

MONDAY THROUGH TUESDAY...SUB-ADVISORY CONDITIONS ARE EXPECTED ACROSS
THE AREA WATERS.

WEDNESDAY...BOTH WINDS AND WAVES WILL RESPOND TO THE NEXT SYSTEM
APPROACHING THE REGION. A SMALL CRAFT ADVISORY MAY BE NEEDED FOR
WEDNESDAY.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT SUNDAY FOR ANZ450>455.
     SMALL CRAFT ADVISORY FROM 2 PM SATURDAY TO 6 PM EDT SUNDAY FOR
     ANZ430-431.

&&

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





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