Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000 FXUS61 KPHI 080848 AFDPHI AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 348 AM EST MON FEB 8 2016 .SYNOPSIS...
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A STRONG AREA OF LOW PRESSURE LOCATED ABOUT 300 MILES EAST OF THE OUTERBANKS OF NORTH CAROLINA WILL MOVE NORTHEAST AND FARTHER OUT TO SEA TODAY. ANOTHER AREA OF LOW PRESSURE IS FORECAST TO DEVELOP TONIGHT NEAR THE SOUTHERN MID-ATLANTIC COAST. AFTER THIS LOW QUICKLY MOVE OUT TO SEA EARLY TUESDAY, A WEAKER AREA OF LOW PRESSURE MAY ORGANIZE TUESDAY AFTERNOON AND NIGHT. AN ARCTIC COLD FRONT WILL APPROACH FROM THE NORTHWEST WEDNESDAY BEFORE MOVING THROUGH THE REGION WEDNESDAY NIGHT. HIGH PRESSURE BUILDS IN FROM THE WEST THURSDAY. A CLIPPER SYSTEM IS EXPECTED TO PASS TO OUR NORTH LATE FRIDAY. IN ITS WAKE, A REINFORCING SHOT OF ARCTIC AIR WILL MAKE IT INTO THE REGION FOR THE WEEKEND.
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&& .NEAR TERM /UNTIL 6 PM THIS EVENING/...
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LOW CONTINUES TO LIFT NORTHEAST OFF SHORE. STILL HAVEN`T SEEN PRECIP PROPAGATE WEST FAR ENOUGH TO MOVE ON SHORE. HOWEVER, A BAND HAS BECOME MORE DEFINED IN THE RADAR MOSAIC, AND STILL EXPECT THIS TO MOVE ONTO THE NORTHERN NEW JERSEY SHORE NEAR DAY BREAK. HRRR AND RAP SEEM TO BE HANDLING THIS WELL. SO WILL CONTINUE THE THREE COUNTY WINTER WEATHER ADVISORY FOR GENERALLY ONE TO 3 INCHES WITH THE HIGHEST AMOUNTS CLOSER TO THE SHORE. FOR THE REST OF THE REGION, EXPECT MOSTLY DRY CONDITIONS THROUGH THE DAY. THE OTHER CONCERN WILL BE WINDS. ALREADY WINDS AT THE SHORE ARE GUSTING 30 TO 35 KT (35 TO 40 MPH). HOWEVER, THE PRESSURE GRADIENT SHOULD BE DECREASING QUICKLY AFTER DAY BREAK AS THE LOW PULLS AWAY, SO THE WINDS WE ARE SEEING NOW ARE LIKELY GOING TO BE THE STRONGEST WINDS OF THE DAY.
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&& .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
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PRECIPITATION, GENERALLY SNOW OR A RAIN AND SNOW MIX WILL START TO MOVE IN FROM THE SOUTHWEST DURING THE EVENING HOURS AS THE LEADING TROUGH LIFTS INTO THE REGION. THE MAIN UPPER LEVEL LOW WILL REMAIN WELL WEST OF THE REGION THROUGH THIS TIME, SO DO NOT EXPECT THE HEAVIEST SNOW TO BE THROUGH THE OVERNIGHT HOURS, AND THE MODELS HAVE IN FACT TRENDED SLIGHTLY DRIER THROUGH THIS PERIOD. EVEN SO, THE SOUTHERN HALF OF THE REGION COULD SEE AS MUCH AS 4 INCHES OF SNOW IF MESOSCALE BANDS DEVELOP EARLY ENOUGH.
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&& .LONG TERM /TUESDAY THROUGH SUNDAY/... AN AREA OF LOW PRES IS EXPECTED TO DEVELOP NR THE MID ATLC CST MON NIGHT. THE GUID IS IN AGREEMENT ON THIS PART. THE DISAGREEMENT LIES IN THE DETAILS, WHICH ARE IMPORTANT. YESTERDAY, THE ECMWF, WENT OUT ON ITS OWN, WITH A STRONGER AND MORE EWD SOLN. IT CONTINUED THAT TREND ON THE OVERNIGHT RUN AND AGAIN ON TODAY`S RUN. IT HAS A MORE CONSOLIDATED LOW CENTER, BRINGS THAT CENTER FURTHER AWAY FROM THE CST, AND HAS MUCH LESS IMPACT ON OUR AREA. WHILE THE ECMWF`S PERFORMANCE HAS BEEN LESS THAN STELLAR THIS WINTER, AND IT IS A CLEAR OUTLIER IN THIS CASE. HOWEVER, ITS OVERALL STATISTICS MEAN IT`S SOLUTION CAN NOT BE TOTALLY IGNORED, AND STRANGER THINGS HAVE HAPPENED. THE REST OF THE OTHER MDLS DO BRING A GENLY LIGHT SNOWFALL TO THE AREA MONDAY NIGHT INTO TUE. PRECIP WILL BEGIN LATER MON AND TEMPS WILL BE WARM ENOUGH TO SUPPORT RAIN OR SNOW THAT HAS A HARD TIME ACCUMULATING IN MOST AREAS AND ON MANY SURFACES DURING THE DAYLIGHT HOURS. AFTER SUNSET, THE SNOW WOULD START TO ACCUMULATE MORE. THE GUID ALSO DIFFERS ON THE AREAS THAT WOULD SEE THE MOST QPF AND CHCS OF HEAVIEST SNOWS. WHILE MOST OF THE SNOW LOOKS TO FALL WOULD BE ON THE LIGHTER SIDE, EVEN WITH THE JANUARY BLIZZARD, THE MDLS WERE HAVING TROUBLE DECIPHERING THIS EVEN 12 HOURS BEFOREHAND. SO FOR NOW, WILL ONLY MAKE INCREMENTAL CHANGES TO THE SNOWFALL AMOUNTS. ATTM, THIS LOOKS LIKE AN ADVY EVENT OR PSBLY LOW END WRNG IN SOME AREAS. ANOTHER COMPLICATING FACTOR IS TEMPS DURG THE DAY ON TUE. TEMPS WILL BE ABV FREEZING IN MANY AREAS, SO THERE CUD BE A MIX OR CHANGEOVER TO RAIN, ESPECIALLY IN SRN AND ERN AREAS, AND MUCH LIKE WE HAD THE OTHER DAY, EVEN WHERE IT SNOWS, IT COULD END UP ACCUMULATING MAINLY ON GRASSY SFCS AND LESS TRAVELED ROADS DURG DAYLIGHT HOURS, IF IT IS NOT COMING DOWN HARD. THINGS SHUD BEGIN TO TAPER OFF TUE NIGHT INTO WED. THEN, A LARGE AREA OF ARCTIC HIGH PRES WILL MOVE INTO THE CNTRL CONUS. THIS HIGH WILL GRADUALLY MOVE EWD THRU THE END OF THE WEEK. EXPECT A GENLY DRY AND BREEZY NWLY FLOW WED THRU SAT. HOWEVER TEMPS WILL NOT MAKE IT ABV FREEZING FROM THU ON. WITH OVERNIGHT LOWS IN THE TEENS. NRML LOWS ARE IN THE LOWER 40S NOW. SO WE ARE LOOKING AT HIGH TEMPS THAT WILL AVERAGE 15 TO 20 DEGREES BELOW NRML, AND WITH THE DAYS GETTING INCREASINGLY LONGER, THIS IS INCREASINGLY DIFFICULT TO ACCOMPLISH, ESPECIALLY FOR AN EXTENDD PD. && .AVIATION /09Z MONDAY THROUGH FRIDAY/...
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THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. FOR THE DELAWARE VALLEY TAF SITES (KPHL, KPNE, KTTN, KILG) AND THE WESTERN TAF SITES (KABE AND KRDG) - MOSTLY VFR CONDITIONS ARE EXPECTED THROUGH AT LEAST 21Z. AFTER THAT, AN APPROACHING TROUGH WILL BRING LOWER CEILINGS, AND EVENTUALLY LOWER VISIBILITIES WITH SNOW. LOWER CEILINGS COULD START TO MOVE IN BETWEEN 21 AND 00Z, BUT DO NOT EXPECT THE SNOW TO MOVE IN UNTIL AFTER 00Z. ONCE SNOW BEGINS TO MOVE IN, EXPECT WIDESPREAD IFR CONDITIONS. OUTLOOK... TUE...PRECIP WILL BE ONGOING DURG THIS TIME AND FOR FOR KPHL, KPNE, KMIV, KACY WILL TRANSITION FROM RAIN OR MIX TO SNOW MON NIGHT. ELSEWHERE WILL BE SNOW MON NIGHT. PRECIP SHUD BE LIGHT FOR THE MOST PART BUT THERE CUD BE SOME MDT OR HVY BURSTS. EXPECT MVFR/IFR CONDS. ON TUE, TEMPS SHUD WARM ENOUGH THAT FOR KPHL, KPNE, KACY, KMIV SHUD AGAIN SEE A MIX OR CHANGEOVER TO RAIN, DEPENDING ON HOW WARM TEMPS GET. LOW TO MDT CONFIDENCE. WED...SOME LINGERING SHSN, THEN IMPROVING TO VFR. BREEZY WITH W TO NW WIND GUSTS AROUND 20 KT. HIGH CONFIDENCE. THU...VFR AND BREEZY WITH NW WIND GUSTING 25 TO 30 KT. HIGH CONFIDENCE.
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&& .MARINE...
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A GALE WARNING CONTINUES ALONG THE COASTAL WATERS. HAVE ALREADY SEEN SEVERAL LOCATIONS ALONG THE COAST REPORT GALE GUSTS. EXPECT THESE STRONG WINDS TO CONTINUE THROUGH MID DAY BEFORE DROPPING OFF SHARPLY. ALTHOUGH SCA CONDITIONS FOR SEAS AND WINDS MAY LINGER FOR MUCH OF THE DAY. ON THE DELAWARE BAY, EXPECT SCA CONDITIONS TO CONTINUE THROUGH AT LEAST SUNRISE. THERE IS LOW CONFIDENCE THAT THEY MAY LINTER FOR A FEW MORE HOURS BEYOND SUNRISE. WINDS WILL BEGIN TO INCREASE AGAIN LATE TONIGHT/EARLY TUESDAY MORNING AHEAD OF THE NEXT LOW MOVING IN FROM THE WEST. OUTLOOK... TUE THROUGH WED...ANOTHER LOW PRESSURE SYS WILL DEVELOP OFF THE MID-ATLANTIC COAST. AN EXTENDED PERIOD OF SCA CONDITIONS LIKELY DURING THIS TIME. IT IS PSBL THAT THERE CUD BE SOME GALES, ESPECIALLY ON WED, BUT CONFIDENCE REMAINS LOW ON THE TRACK AND STRENGTH OF THE LOW. THU...SOLID SCA CONDITIONS. NW WINDS BEHIND A CFP, WITH THE BEST CHC FOR GALES.
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&& .TIDES/COASTAL FLOODING...
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***MODERATE COASTAL FLOODING IS LIKELY AT SANDY HOOK FOR BOTH HIGH TIDE CYCLES TODAY. MINOR COASTAL FLOODING IS LIKELY NEAR THE THIS MORNINGS HIGH TIDE FOR OTHER LOCATIONS. THERE IS INCREASING POTENTIAL FOR MODERATE COASTAL FLOODING NEAR THE TUESDAY MORNING HIGH TIDE*** HIGH PRESSURE WILL ANCHOR OVER EASTERN QUEBEC/LABRADOR WHILE LOW PRESSURE PASSING OFFSHORE WELL TO THE SOUTHEAST UNDERGOES EXPLOSIVE DEEPENING OVERNIGHT AND THROUGH THE DAY MONDAY. WITH THE AFOREMENTIONED HIGH REMAINING TO OUR NORTH, A BROAD AREA OF LOW PRESSURE WILL DEVELOP OFF THE OUTER BANKS MONDAY NIGHT AND PASS OFFSHORE SOUTHEAST OF OUR REGION DURING THE DAY TUESDAY. THESE TWO SYSTEMS WILL MAINTAIN AN ONSHORE FLOW ALONG THE COAST THRU TUESDAY, WITH ONLY A BRIEF PAUSE MONDAY AFTERNOON AND VERY EARLY MONDAY NIGHT, AS THE PRESSURE GRADIENT RELAXES BETWEEN SYSTEMS. SETTING THE STAGE, ASTRONOMICAL TIDES WILL BE HIGH EARLY THIS WEEK, TO DUE TO THE NEW MOON ON MONDAY. AT SANDY HOOK, WE ALREADY SAW A LARGE DEPARTURE WITH THE LOW TIDE AT SANDY HOOK EARLIER, AND WINDS HAVE INCREASED SHARPLY AND ARE EXPECTED TO CONTINUE THROUGH THE HIGH TIDE CYCLE. THUS, MODEL GUIDANCE AND A LOCAL REGRESSION PROGRAM INDICATE THAT A DEPARTURE OF OVER 2 FEET IS POSSIBLE WITH THE NEXT HIGH TIDE, OR JUST ENOUGH TO REACH MODERATE FLOODING THRESHOLDS. WITH THE CONTINUED NORTHEAST FLOW AND HIGH WAVE ACTION, EXPECT THAT IT COULD BE A SIMILAR STORY FOR TONIGHTS HIGH TIDE, THOUGH THAT IS THE LOWER OF THE ASTRONOMICAL TIDES. THUS THE WARNING INCLUDES BOTH HIGH TIDE CYCLES TODAY. CONTINUED THE WATCH FOR TOMORROWS HIGH TIDE CYCLE. FOR THE REST OF THE COAST...WITH HIGH ASTRONOMICAL TIDES, WE EXPECT A SURGE OF 1 TO 1.5 FEET. WE HAVE HIGH CONFIDENCE IN WIDESPREAD MINOR COASTAL FLOODING. WE HAVE ALSO TEMPERED DOWN THE HIGH-BIASED ET AND ESTOFS GUIDANCE DUE TO A RESIDUAL OF NEARLY 1 FOOT IN SPOTS. A COASTAL FLOOD ADVISORY HAS BEEN ISSUED FOR THE MONDAY MORNING HIGH TIDE ALONG THE CENTRAL AND SOUTHERN NJ AND DE OCEANFRONT, AS WELL AS DELAWARE BAY. THERE IS A BIT MORE UNCERTAINTY ON WHETHER WE REACH THE MINOR THRESHOLD AT REEDY POINT, WHICH IS LARGELY DEPENDENT ON EKMAN TRANSPORT IN A NORTHEAST FLOW, BUT WE EXPECT IT TO BE CLOSE NONETHELESS. A COASTAL FLOOD ADVISORY CONTINUES FOR THE CENTRAL AND SOUTHERN NJ AND DE OCEANFRONT FOR THE MONDAY EVENING HIGH TIDE, AS MINOR COASTAL FLOODING IS EXPECTED TO LINGER. FOR THE TUESDAY MORNING HIGH TIDE, A MORE EASTERLY COMPONENT/LONGER FETCH TO THE WIND WILL HAVE A GREATER IMPACT ALONG THE ENTIRE COAST, INCLUDING DELAWARE BAY, AND PORTIONS OF THE TIDAL DELAWARE. WE AGREE WITH THE STRONGER GFS WINDS, ESPECIALLY GIVEN THE SYNOPTIC SETUP. THE MAIN UNCERTAINTY IS REGARDING A BROAD LOW PRESSURE/TROUGH MOVING NORTHEASTWARD ALONG THE COAST, WHICH MAY ALLOW WINDS TO QUICKLY RELAX NEAR THE TIME OF HIGH TIDE, PARTICULARLY DELMARVA AND FAR SOUTHERN NJ. NEVERTHELESS, ASIDE FROM A BRIEF LULL IN THE FLOW MONDAY AFTERNOON AND VERY EARLY MONDAY NIGHT, WE`LL HAVE HAD NEARLY 48 HOURS DURATION OF ONSHORE FLOW, WHICH WILL MAKE FOR HIGHER TIDAL DEPARTURES COMPARED TO MONDAY MORNING, IN ADDITION TO THE ASTRONOMICALLY HIGHER TIDES. IN TERMS OF GUIDANCE, WE SIDED MORE WITH THE HIGHER ETSS SURGE OF 2 TO 2.5 FEET, EVEN CONSIDERING THE AFOREMENTIONED RESIDUAL. A COASTAL FLOOD WATCH HAS BEEN ISSUED FOR THE TUESDAY MORNING HIGH TIDE FOR THE NJ AND DE OCEANFRONT WITH THE HIGHEST CONFIDENCE IN WIDESPREAD MODERATE COASTAL FLOODING FOR CENTRAL AND NORTHERN NJ. ELSEWHERE, WIDESPREAD MINOR COASTAL FLOODING IS ANTICIPATED, PERHAPS UP TO PHILADELPHIA, GIVEN THE MORE EASTERLY FLOW UP DELAWARE BAY. FOR THESE AREAS, A COASTAL FLOOD ADVISORY WILL LIKELY BE NEEDED.
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&& .PHI WATCHES/WARNINGS/ADVISORIES...
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PA...WINTER STORM WATCH FROM LATE TONIGHT THROUGH LATE TUESDAY NIGHT FOR PAZ070-071-101-102. NJ...WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR NJZ012>014-020-026. COASTAL FLOOD WATCH FROM LATE TONIGHT THROUGH TUESDAY AFTERNOON FOR NJZ012>014-020>027. COASTAL FLOOD ADVISORY UNTIL 4 AM EST TUESDAY FOR NJZ020>027. COASTAL FLOOD ADVISORY FROM 9 AM THIS MORNING TO 1 PM EST THIS AFTERNOON FOR NJZ016. WINTER STORM WATCH FROM LATE TONIGHT THROUGH LATE TUESDAY NIGHT FOR NJZ016>023-027. COASTAL FLOOD WARNING UNTIL 10 PM EST THIS EVENING FOR NJZ012>014. DE...COASTAL FLOOD WATCH FROM LATE TONIGHT THROUGH TUESDAY AFTERNOON FOR DEZ002>004. COASTAL FLOOD ADVISORY UNTIL 4 AM EST TUESDAY FOR DEZ002>004. COASTAL FLOOD ADVISORY FROM 9 AM THIS MORNING TO 1 PM EST THIS AFTERNOON FOR DEZ001. WINTER STORM WATCH FROM LATE TONIGHT THROUGH LATE TUESDAY NIGHT FOR DEZ001-002. MD...WINTER STORM WATCH FROM LATE TONIGHT THROUGH LATE TUESDAY NIGHT FOR MDZ008-012-015. MARINE...GALE WARNING UNTIL NOON EST TODAY FOR ANZ450>455. SMALL CRAFT ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR ANZ430-431.
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&& $$ SYNOPSIS...KLEIN NEAR TERM...JOHNSON SHORT TERM...JOHNSON LONG TERM...NIERENBERG AVIATION...JOHNSON/NIERENBERG MARINE...JOHNSON/NIERENBERG TIDES/COASTAL FLOODING...

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