Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000 FXUS61 KPHI 280428 AFDPHI AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 1228 AM EDT SUN JUN 28 2015 .SYNOPSIS... A COMPLEX AREA OF LOW PRESSURE WILL LIFT NORTHEASTWARD ACROSS THE NORTHEASTERN STATES THROUGH SUNDAY NIGHT. HIGH PRESSURE WILL BRIEFLY MOVE INTO THE AREA FOR MONDAY. A COLD FRONT WILL SETTLE ACROSS OUR REGION LATE TUESDAY AND WEDNESDAY BEFORE STALLING TO OUR SOUTH ON THURSDAY. THE FRONT MAY BEGIN TO LIFT NORTHWARD ACROSS OUR AREA ON FRIDAY AND SATURDAY. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... THE INITIAL LOW IS FORECAST TO MOVE FROM NORTHEASTERN OHIO INTO NORTHWESTERN PENNSYLVANIA OVERNIGHT. THE SECONDARY LOW WAS LOCATED NEAR THE NATION`S CAPITAL AROUND MIDNIGHT AND IT IS EXPECTED TO REACH SOUTHERN NEW JERSEY TOWARD DAYBREAK. THE DEVELOPMENT AND PROGRESS OF THE SECONDARY LOW WILL CONTINUE TO PUSH THE STRONGEST OF THE ONSHORE FLOW OUT OF OUR REGION AND INTO NEW ENGLAND OVERNIGHT. THE COVERAGE AND THE INTENSITY OF THE PRECIPITATION WILL CONTINUE TO DIMINISH. AS A RESULT, WE HAVE CANCELLED THE FLOOD WATCH. ONE FLOOD WARNING, ONE FLASH FLOOD WARNING AND ONE FLOOD ADVISORY REMAINED IN EFFECT AROUND MIDNIGHT. ALL THREE WILL EXPIRE BEFORE DAYBREAK AS THE FLOOD WATERS CONTINUE TO SUBSIDE. TEMPERATURES ARE NOT EXPECTED TO CHANGE MUCH FROM THE MIDNIGHT READINGS DURING THE BALANCE OF THE NIGHT. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 AM MONDAY/... NO CHANGES HERE TO PREVIOUS FORECAST WITH CURRENT ACTIVE WEATHER. THE STRONG LOW WILL BE ACROSS NRN NJ SUNDAY MORNING. THE PRESSURE GRADIENT WILL FAVOR A DRYING WRLY FLOW ACROSS THE AREA...SO THE STEADY PRECIP ACROSS THE NORTH EARLY WILL LIFT OUT...LEAVING OUR AREA IN AN IMPROVING PATTERN. A COUPLE SCT SHOWERS POSSIBLE EARLY...THEN POPS DECREASE THROUGH THE DAY. SKIES WILL BECOME SUNNY FROM S TO N AS THE DAY PROGRESSES. HIGH TEMPERATURES WILL RISE INTO THE LOW 80S ACROSS THE SRN AREAS...WHERE WE HAVE THE GREATEST DURATION OF SUNSHINE. ACROSS THE NRN AREAS TEMPS WILL TOP OUT IN THE MID/UPPER 70S. WINDS...MOSTLY WRLY AND BECOME GUSTY (20 TO 25 MPH) DURING THE AFTERNOON. && .LONG TERM /MONDAY THROUGH SUNDAY/... OVERVIEW... AMPLIFIED MID-LEVEL PATTERN DURING THE D+3 THRU D+7 PERIOD FEATURES A RIDGE ALONG THE WEST COAST OF NOAM AND A TROUGH OVER THE GRT LKS. STRONG HIGH LATITUDE BLOCKING BY JUNE STANDARDS IS ALSO PRESENT... AND THIS IS REFLECTED IN THE -NAO/+PNA PATTERN...THAT IS EXPECTED TO PERSIST AT LEAST INTO THE 4TH OF JULY WEEKEND. THE MAIN UNCERTAINTY IN THE FORECAST IS WITH REGARD TO THE AMPLITUDE AND TIMING OF S/WV ENERGY TRAVERSING THE WEST COAST RIDGE...AS THE GRT LAKES TROUGH TAKES ON AN INCREASINGLY NEGATIVE TILT BY MID-WEEK. OVERALL...A CYCLONIC FLOW ALOFT AND BLW AVG HEIGHTS WILL LEAD TO UNSETTLED WEATHER THRU THE PERIOD WITH TEMPS GENERALLY AOB SEASONAL NORMS. DETAILS... SUN NIGHT AND MON...LOW LEVEL MOISTURE ASSOCIATED WITH COMMA HEAD WILL GRADUALLY DECREASE AS LOW PRES DEPARTS AND FLOW BECOMES WEST. A -SHRA IS POSSIBLE EARLY SUN NIGHT OVER THE POCONOS. INCREASING SUNSHINE EXPECTED ON MON...AS S/WV RIDGING AND THE LEFT ENTRANCE REGION OF THE JET MOVE IN ALOFT...SUPPORTING A WEAK RIDGE OF HIGH PRES AT THE SURFACE. MAX TEMPS WILL AVERAGE AROUND 5 DEGREES BELOW AVG...WITH MUCH MORE COMFORTABLE HUMIDITY LEVELS. TUE...LOW PRES MOVING THRU THE GRT LKS WILL LEAD TO A WARM FROPA... BUT ONSHORE FLOW MAY INHIBIT THIS...AND THE FRONT COULD STALL FOR A TIME ACROSS THE REGION. LOW AND MID-LEVEL MOIST WILL INCREASE AS A S/WV APPROACHES THE REGION...WITH CONSIDERABLE CLOUDINESS EXPECTED. ATTM...BEST CHANCE OF PRECIP IS NORTHWEST OF THE I-95 CORRIDOR... WHERE DEEPER MOISTURE AND LIFT COINCIDE. THERE IS THE POTENTIAL FOR CONVECTION...WHICH WILL BE DEPENDENT ON THE LOCATION OF THE WARM FRONT AND AMOUNT OF INSOLATION. ALTHOUGH CAPE AND SHEAR ARE BOTH UNCERTAIN...MODEL SOLUTIONS INDICATE A CONSIDERABLE AMOUNT OF LOW- LEVEL HELICITY INVOF THE BOUNDARY...SO THIS WILL BEAR WATCHING. WED...LOW PRES MOVES THRU THE ST. LAWRENCE VALLEY...AS A BONAFIED COLD FRONT APPROACHES FROM THE WEST. THIS IS WHERE MODEL SOLUTIONS BEGIN TO DIVERGE WITH RESPECT TO TIMING OF THE COLD FROPA...WHICH WILL DETERMINE CONVECTIVE POTENTIAL. ATTM...MODELS HAVE THE FRONT TO THE I-95 CORRIDOR BY 18Z...WHICH PLACES THE EMPHASIS FOR CONVECTION ALONG AND EAST OF HERE. THE FRONT WILL ALSO SLOW DOWN...WHICH COULD PROLONG CONVECTIVE CHANCES INTO WED NIGHT OVER DELMARVA. MAX TEMPS ARE EXPECTED TO BE AOA SEASONAL LEVELS. THU...HIGH PRES BRIEFLY MOVES IN...BUT STALLED FRONT NEAR DELMARVA COULD LEAD TO CONSIDERABLE CLOUDINESS AND EVEN SOME -SHRA OVER THIS AREA. TO THE NORTH...ENOUGH DRY AIR SHOULD FILTER IN FOR AT LEAST PARTIAL SUNSHINE. FRI AND SAT...CONSIDERABLE SPATIAL AND TEMPORAL MODEL SPREAD EXISTS IN HANDLING S/WV ENERGY TRAVERSING GRT LKS TROUGH. SOLUTIONS VARY... FROM THE FLATTER UKMET TO THE MORE AMPLIFIED ECMWF. THE LATTER WOULD LEAD TO ANOTHER STORM SYSTEM MOVING THRU THE GRT LKS W/REDEVELOPMENT OVER THE MID-ATLANTIC...AND THE POTENTIAL FOR MORE HEAVY RAINFALL. THIS WILL HAVE TO BE MONITORED...GIVEN RAINFALL OCCURRING THIS WEEKEND...THUS ANTICIPATED WET ANTECEDENT CONDITIONS. && .AVIATION /04Z SUNDAY THROUGH THURSDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY, AND SURROUNDING AREAS. IFR CONDITIONS WILL CONTINUE OVERNIGHT. BY SUNRISE CONDITIONS SHOULD BE GENERALLY MVFR WITH VFR DEVELOPING ACROSS THE TAF SITES DURING SUNDAY MORNING. WINDS MOSTLY ERLY/SERLY THEN SWITCHING TO WRLY BEFORE SUNRISE. OUTLOOK... SUN NIGHT AND MON...VFR CONDITIONS EXPECTED. TUE THRU WED...MVFR POSSIBLE IN SHRA/TSRA...PARTICULARLY I-95 CORRIDOR TERMINALS AND POINTS NORTHWEST. THU...VFR CONDITIONS. MVFR POSSIBLE IN SHRA/TSRA...ESPECIALLY SOUTH NJ AND DELMARVA TERMINALS. LOW CONFIDENCE. && .MARINE... PERSISTENT GALE FORCE WIND GUSTS DEVELOPED AND WENT AHEAD AND ISSUED A SHORT FUSED GALE WARNING FOR WATERS FROM SANDY HOOK TO LITTLE EGG INLET. GALE WARNING UNTIL 400 AM SUNDAY. ELSEWHERE WE WILL CONTINUE WITH THE SCA FLAG FOR THE OCEAN WATERS INTO SUNDAY. SCA FLAG FOR DEL BAY WILL CONTINUE INTO THE PRE-DAWN HOURS OF SUNDAY. OUTLOOK... SUN NIGHT...SCA NOW IN EFFECT THRU 21Z SUN MAY NEED TO BE EXTENDED INTO SUNDAY NIGHT FOR RESIDUAL 5 FOOT SEAS. MONDAY...WINDS AND SEAS ARE ANTICIPATED TO BE BLW SCA THRESHOLDS. TUESDAY...INCREASE IN SOUTHERLY FLOW MAY BUILD SEAS ON THE OCEAN SCA CRITERIA. WEDNESDAY...SUBSIDING SEAS WITH SUB-SCA CONDITIONS EXPECTED ATTM. && .TIDES/COASTAL FLOODING... HIGH TIDE HAS PASSED ON THE LOWER PART OF THE DELAWARE RIVER AND THE POTENTIAL FOR MINOR TIDAL FLOODING HAS ENDED. AS A RESULT, WE HAVE CANCELLED THE COASTAL FLOOD ADVISORY. && .RIP CURRENTS... SEAS OFF THE COASTS OF DELAWARE AND NEW JERSEY WILL REMAIN AGITATED ON SUNDAY AS LOW PRESSURE CONTINUES TO LIFT NORTHEASTWARD ACROSS THE NORTHEASTERN STATES. AS A RESULT, THERE WILL BE A MODERATE RISK OF RIP CURRENTS ALONG THE NEW JERSEY SHORE AND AT THE DELAWARE BEACHES. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ452>455. GALE WARNING UNTIL 4 AM EDT EARLY THIS MORNING FOR ANZ450-451. SMALL CRAFT ADVISORY UNTIL 6 AM EDT EARLY THIS MORNING FOR ANZ430-431. && $$ SYNOPSIS...FRANCK/GORSE NEAR TERM...IOVINO SHORT TERM...O`HARA LONG TERM...FRANCK AVIATION...FRANCK/SZATKOWSKI/O`HARA MARINE...FRANCK/SZATKOWSKI/O`HARA TIDES/COASTAL FLOODING...IOVINO RIP CURRENTS...IOVINO

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