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Area Forecast Discussion
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000
FXUS61 KPHI 222047
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
447 PM EDT WED OCT 22 2014

.SYNOPSIS...
AN AREA OF LOW PRESSURE OFFSHORE WILL CONTINUE TO STRENGTHEN AS IT 
SLOWLY TRACKS NORTHEASTWARD TONIGHT. THIS STORM SYSTEM SHOULD BE OFF 
THE NEW ENGLAND COAST LATER THURSDAY INTO FRIDAY, THEN MOVE INTO 
NOVA SCOTIA FRIDAY NIGHT. HIGH PRESSURE IS FORECAST TO BUILD TOWARD 
OUR AREA FROM THE SOUTHWEST FRIDAY AND SATURDAY, THEN A COLD FRONT 
IS EXPECTED TO MOVE THROUGH SATURDAY NIGHT. HIGH PRESSURE BUILDS IN 
FOR LATER SUNDAY AND MONDAY BEFORE SHIFTING OFFSHORE TUESDAY.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
HE MID LEVEL LOW WAS CENTERED OVER THE WATERS OFF VIRGINIA THIS 
AFTERNOON. IT SHOULD LIFT NORTHEASTWARD TO THE WATERS OFF NEW JERSEY 
AND LONG ISLAND TOWARD MORNING. MEANWHILE, THE SURFACE LOW WAS 
CENTERED ABOUT 150 MILES OFF THE DELAWARE COAST. THAT FEATURE IS 
EXPECTED TO DRIFT ABOUT 50 MILES TO THE EAST DURING THE COURSE OF 
THE NIGHT.

IT WILL REMAIN OVERCAST AND CHILLY IN OUR REGION FOR TONIGHT. LOW 
TEMPERATURES ARE ANTICIPATED TO BE MAINLY IN THE 40S. THE WIND 
SHOULD BACK FROM THE NORTH TO THE NORTHWEST AT SPEEDS AROUND 10 TO 
15 MPH WITH GUSTS INTO THE 20S.

THE RAIN THAT WAS ROTATING AROUND THE COASTAL SYSTEM WILL LIKELY  
MAINTAIN A NORTHEAST TO SOUTHWEST ORIENTATION IN OUR REGION DURING 
THE NIGHT. IT SHOULD SETTLE PRIMARILY OVER THE COASTAL PLAIN IN NEW 
JERSEY AND DELAWARE DURING THE EVENING BEFORE LIFTING NORTHWARD 
OVERNIGHT. THERE MAY BE A PERIOD OF MODERATE RAINFALL IN COASTAL 
AREAS OF NEW JERSEY THIS EVENING DEPENDING UPON HOW FAR WESTWARD THE 
HEAVIER RAIN BANDS OFF THE COAST MOVE. OTHERWISE, RAINFALL AMOUNTS 
IN DELAWARE AND NEW JERSEY SHOULD BE MOSTLY IN THE QUARTER TO HALF 
INCH RANGE, WITH LESS THAN A QUARTER INCH OF RAIN EXPECTED IN 
EASTERN PENNSYLVANIA AND NORTHEASTERN MARYLAND.

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/...
THE MID LEVEL LOW AND THE SURFACE LOW ARE FORECAST TO MOVE TOWARD 
THE WATERS OFF CAPE COD ON THURSDAY. THE PRECIPITATION ASSOCIATED 
WITH THE COASTAL SYSTEM WILL BEGIN TO LIFT NORTHEASTWARD, AS WELL.

WE ARE EXPECTING THE RAIN TO BECOME SHOWERY AND END GRADUALLY FROM 
SOUTHWEST TO NORTHEAST ON THURSDAY.

THE SKY SHOULD REMAIN CLOUDY WITH A NORTHWEST WIND IN THE 10 TO 20 
MPH RANGE WITH GUSTS OF 20 TO 30 MPH. THE CLOUDS AND THE NORTHWEST 
FLOW WILL LIKELY KEEP TEMPERATURES FROM GETTING ABOVE THE 50S ON 
THURSDAY AFTERNOON.

&&

.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
MODEL CONSENSUS THROUGH THE FIRST COUPLE DAYS OF THE EXTENDED IS 
PRETTY GOOD, BUT ONCE YOU GET PAST SATURDAY A MUCH LARGER SPREAD IS 
SEEN. WE WILL, HOWEVER, BE TRANSITIONING FROM TROUGHINESS TO DEGREES 
OF RIDGING THROUGH THE EXTENDED, STARTING BY EARLY NEXT WEEK. FOR 
THE MOST PART WE MAINTAIN A RELATIVELY DRY LONGTERM FROM SATURDAY 
ONWARD AS RIDGING BEGINS TO BUILD TO OUR SOUTH-SOUTHWEST.

FRIDAY...UPPER LEVEL LOW CONTINUES TO SPIN AND PULL AWAY TO OUR 
NORTHEAST WITH JUST SOME LINGERING BACKSIDE SHOWERS POSSIBLE ACROSS OUR 
NORTHERN ZONES. THE OVERALL TREND ON FRIDAY IS FOR DRYING AS THE 
STRONG PRESSURE GRADIENT AND NORTHWEST WINDS REMAIN IN PLACE. 
TEMPERATURES SHOULD BE ABLE TO REBOUND BACK IN THE LOW TO MID-60S 
WITH LESS CLOUD COVER THAN PREVIOUS DAYS AND THE LACK OF SHOWERS. 

SATURDAY AND SUNDAY...HIGH PRESSURE BUILDS TO OUR SOUTH SATURDAY, 
HOWEVER A STRONG SHORT WAVE DIVING SOUTHEASTWARD FROM THE GREAT 
LAKES WILL DIG ANOTHER UPPER-LEVEL TROUGH ACROSS THE NORTHEAST LATER 
SATURDAY INTO SUNDAY. THIS WILL TOSS A COLD FRONT ACROSS OUR AREA 
SATURDAY NIGHT BUT STILL UNSURE IF WE WILL SEE A DRY PASSAGE WITH 
THIS SYSTEM. THINKING THAT THE ATMOSPHERE WILL NOT HAVE MUCH TIME TO 
MODIFY AHEAD OF THE FRONT AND HOW MUCH INFLUENCE THE ENERGY WILL 
HAVE AS IT COMES IN ON THE HEELS OF THE ONCE CUT-OFF LOW. WITH THE 
LIMITED AMOUNT OF MOISTURE EXPECTED IT SHOULD RESULT IN A GENERALLY 
DRY FRONTAL PASSAGE. THE ASSOCIATED SURFACE LOW LOOKS TO INTENSIFY 
AS IS EXITS NEW ENGLAND, WHICH MEANS A TIGHTENING PRESSURE GRADIENT 
DOWN INTO THE MID ATLANTIC SUNDAY. AS A RESULT, A BREEZY DAY MAY 
OCCUR AS MIXING DEEPENS. HIGH PRESSURE THEN STARTS TO BUILD IN 
SUNDAY NIGHT.

MONDAY - WEDNESDAY...AN UPPER-LEVEL RIDGE SLIDES TOWARD THE EAST 
ALLOWING HIGH PRESSURE TO BUILD ACROSS OUR AREA MONDAY BEFORE 
SHIFTING OFFSHORE TUESDAY. THIS IS EXPECTED TO RESULT IN WARMING 
CONDITIONS, ESPECIALLY AS WAA DEVELOPS TUESDAY AHEAD OF THE NEXT 
COLD FRONT. NO MAJOR CHANGES WERE MADE FOR THIS TIME FRAME, WITH 
JUST SOME BLENDING IN OF THE NEW 12Z WPC GUIDANCE.

&&

.AVIATION /21Z WEDNESDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, 
KMIV, KACY AND SURROUNDING AREAS.

GENERALLY, MVFR CEILINGS ARE ANTICIPATED THROUGH TONIGHT IN OUR 
REGION. PERIODS OF RAIN ARE EXPECTED WITH THE HEAVIEST OF THE 
RAINFALL BEING MAINLY IN NEW JERSEY.

THE CEILINGS ARE FORECAST TO LIFT GRADUALLY INTO THE VFR CATEGORY 
FROM SOUTHWEST TO NORTHEAST ON THURSDAY. THE RAIN IS ANTICIPATED TO 
BECOME MORE SHOWERY AND IT SHOULD END AT OUR TAF SITES BY MID TO 
LATE AFTERNOON.

THE WIND IS FORECAST TO FAVOR THE NORTH INTO THIS EVENING, THEN IT 
SHOULD BACK TO THE NORTHWEST FOR OVERNIGHT AND THURSDAY. SUSTAINED 
SPEEDS ARE EXPECTED TO BE AROUND 10 TO 15 KNOTS WITH GUSTS INTO THE 
20S.

OUTLOOK...
FRIDAY...VFR. CONTINUED NORTHWEST WINDS WITH GUSTS AROUND 20 KNOTS. 
SOME LINGERING SHOWERS POSSIBLE NORTH OF ABE. MEDIUM CONFIDENCE, 
LOWER ON SHOWERS.

SATURDAY - SUNDAY...VFR. WINDS SHIFT TO THE WEST-SOUTHWEST. DRY COLD 
FRONT PASSAGE EXPECTED LATE SATURDAY NIGHT. MEDIUM CONFIDENCE.

MONDAY...VFR.

&&

.MARINE...
THE GALE WARNING HAS BEEN EXTENDED UNTIL 600 PM THURSDAY FOR OUR 
OCEAN WATERS AND FOR THE LOWER PART OF DELAWARE BAY. THE CIRCULATION 
AROUND THE SLOW MOVING LOW OFF THE COAST SHOULD MAINTAIN A NORTH TO 
NORTHWEST WIND OVER OUR WATERS WITH GUSTS OF 35 TO 40 KNOTS 
ANTICIPATED. A SMALL CRAFT ADVISORY REMAINS IN PLACE FOR THE UPPER 
PART OF DELAWARE BAY. GUSTS THERE SHOULD PEAK AROUND 30 KNOTS.

OUTLOOK...
FRIDAY - SATURDAY MORNING...SCA CONDITIONS PERSIST, ONCE THE GALES 
COME DOWN, AS THE COASTAL LOW PRESSURE CONTINUES TO MOVE NORTHEAST 
THOUGH THE PRESSURE GRADIENT SHOULD BE RELAXING BY FRIDAY NIGHT. 
NORTHWEST WINDS AROUND 15 TO 20 KNOTS. MEDIUM CONFIDENCE. 

SATURDAY...SUB-SCA. WESTERLY WINDS AROUND 15 KNOTS. MEDIUM 
CONFIDENCE.

SUNDAY...PERIOD OF SCA POSSIBLE BEHIND A PASSING COLD FRONT. MEDIUM 
CONFIDENCE.

MONDAY...SUB-SCA. MEDIUM CONFIDENCE.

&&

.TIDES/COASTAL FLOODING...
TIDES ARE RUNNING HIGH DUE TO A COMBINATION OF THE STORM OFF THE
COAST AND THE APPROACHING NEW MOON. HIGH TIDES OCCUR THIS EVENING
BEFORE MIDNIGHT ALONG THE OCEAN, THEN AGAIN ON THURSDAY MORNING ALONG
THE OCEAN AROUND NOON. TOMMORROW/S HIGH TIDE HAS THE HIGHER
ASTRONOMICAL CONTRIBUTION, BUT BY THAT TIME THERE SHOULD BE A
WELL-ESTABLISHED NORTHWEST WIND. RIGHT NOW THE ONLY FLOODING WE/RE
EXPECTING WOULD BE ISOLATED MINOR FLOODING BELOW OUR ESTABLISHED
THRESHOLDS NEEDED FOR AN ADVISORY. HOWEVER...WE WILL BE KEEPING AN
EYE ON THE SITUATION AND ISSUE ANY ADDITIONAL STATEMENTS IF
NECESSARY.


&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...GALE WARNING UNTIL 6 PM EDT THURSDAY FOR ANZ431-450>455.
     SMALL CRAFT ADVISORY UNTIL 6 PM EDT THURSDAY FOR ANZ430.

&&

$$
SYNOPSIS...GORSE
NEAR TERM...IOVINO
SHORT TERM...IOVINO
LONG TERM...GORSE/HEAVENER
AVIATION...IOVINO/HEAVENER
MARINE...IOVINO/HEAVENER
TIDES/COASTAL FLOODING...MIKETTA







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