Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000 FXUS61 KPHI 162048 AFDPHI Area Forecast Discussion National Weather Service Mount Holly NJ 348 PM EST Fri Nov 16 2018 .SYNOPSIS... High pressure is forecast to build to our west on Saturday before weakening Saturday night as a weak cold front moves across the area. High pressure builds to our north Sunday, before another frontal system moves across the area Sunday night into Monday. Yet another frontal system is possible around Tuesday, with high pressure for the middle of the week. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... The deep low pressure system continues to move northeast of the area while high pressure well to the west starts to influence the area. The strong pressure gradient between the two systems continues to produce gusty W to NW winds across the area. These winds will decrease late this afternoon and further diminish overnight. The afternoon clouds that have developed over the area will decrease tonight leaving mostly clear skies. Low temperatures tonight will drop into the upper 20s across the north and reach the low/mid 30d elsewhere. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/... High pressure will continue to push east, reaching the Appalachians Saturday. Fair weather will continue across the region with partly to mostly sunny skies expected. Temperatures will continue below normal, with highs only reaching the low/mid 40s across the far north/west and upper 40s to around 50 S/E. Winds will be less gusty than today with speeds only around 8 to 12 mph expected. && .LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/... High pressure will continue to weaken to our west overnight as a frontal boundary approaches from the northwest Saturday night. The front may wash our overnight before reaching our area, then high pressure briefly builds across the area early on Sunday. Through the day Sunday, a surface boundary is forecast to move into our area from the west as the high pressure moves eastward. Enhanced lift and moisture are forecast to move across the area Sunday through Monday as the boundary slowly traverses the area. This could begin a period of showers to much of the area, especially northeast Pennsylvania and northern New Jersey later Sunday through Monday night, before shifting to the east later Monday into Monday night. Details in thermal profiles are still quite uncertain, but there is the potential for another mix of rain and snow for some areas. Northeast Pennsylvania and northern New Jersey have the best chance of seeing snow, while areas farther south have the best chance of staying rain. If snow occurs across the northern areas, there could be some accumulations later Sunday into Monday. Another quick moving frontal boundary is expected to sweep across the area on Tuesday, which could bring another chance of showers. This front is expected to be colder, and would bring a better chance of snow to the much of the area. Neither of these systems look to be a significant snow producer at this point, although it would not be surprising to see a couple of inches across portions of northeast Pennsylvania and northern New Jersey later Sunday through Tuesday. As we move into Wednesday, high pressure builds across the area, then offshore on Thursday. This brings fair weather back to the area, along with cooler conditions on Wednesday. Once the high moves offshore Thursday, temperatures warm slightly compared to Wednesday, but will remain below normal. The forecast for Friday into the weekend becomes uncertain in specifics, but the long term guidance does indicated the potential for another coastal storm. There are timing and placement differences between the models, but they each show a low near the east coast at some point between Friday and Sunday. && .AVIATION /20Z FRIDAY THROUGH WEDNESDAY/... The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas. Tonight...VFR with decreasing clouds. A few SC still expected across the N/W areas into the evening. Winds settling back to 5 to 10 knots after midnight. Saturday...VFR expected with mostly clear skies. Some Ci/Cs clouds may spread over the area during the afternoon. Winds will be mostly W around 10 knots. OUTLOOK... Saturday night...MVFR conditions may occur periodically. Sunday-Tuesday...Periods of MVFR conditions possible with a chance of showers. Tuesday night-Wednesday...VFR conditions expected. && .MARINE... We have lowered the remaining Gale and issued a SCA for the ocean waters with the 330 PM issuance. The SCA flag for Delaware Bay will remain through the overnight and end a little before the ocean SCA. Deep low pressure will continue to move away tonight while high pressure begins to reach the area late tonight and Saturday. Fair weather is expected with slowly lowering seas. OUTLOOK... Saturday night-Tuesday...Conditions expected to remain below advisory levels with west-northwest winds 10-15 knots. Tuesday night...Conditions may increase to near Small Craft Advisory levels. Wednesday...Conditions expected to be below advisory levels. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...None. NJ...None. DE...None. MD...None. MARINE...Small Craft Advisory until 11 AM EST Saturday for ANZ450>455. Small Craft Advisory until 5 AM EST Saturday for ANZ430-431. && $$ Synopsis...Robertson Near Term...O`Hara Short Term...O`Hara Long Term...Robertson/O`Hara Aviation...Robertson/O`Hara Marine...Robertson/O`Hara is the U.S. government's official web portal to all federal, state and local government web resources and services.