Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000 FXUS61 KPHI 221716 AFDPHI Area Forecast Discussion National Weather Service Mount Holly NJ 1216 PM EST Wed Nov 22 2017 .SYNOPSIS... A cold front and low pressure system east of the mid Atlantic coast will move east of New England by this evening. High pressure will build toward our area tonight, and control the weather Thursday and Friday. A cold front is forecast to move across the mid Atlantic states later Saturday while an area of low pressure moves northeastward offshore the Mid Atlantic coast. High pressure builds across the area Monday, then offshore Tuesday. && .NEAR TERM /THROUGH TONIGHT/... 1150A and 1230 PM ESTF: our new 330 PM office guidance has been issued with the 1150 AM and 1230 PM ESTF updates. There may be some minor modifications at 330 PM. This afternoon...raised temps a bit per obs and added 5MPH to the gusts (generally 25-35 mph range). Showers now ending NJ coast. Cold air advection developing nicely. Considerable cloudiness parts of ne PA and nw NJ but otherwise partly to mostly sunny elsewhere, except becoming mostly sunny along the NJ coast. Tonight...Mostly clear with diminishing gusts...tho still a breeze in the urban centers and along the coasts where boundary layer instability is greater with the decent cold air advection. Lows 4 to 8 degrees below normal. This forecast was a 50 50 blend of the 12z/22 GFS/NAM MOS. && .SHORT TERM /THURSDAY/... Sunny with spotty high cloudiness early in the day and then a general deck of waa mid or high clouds arriving from the west northwest late in the day reaching to near I-95 around 6 PM. Light northwest to west wind. Mixing doesn`t look too good so a fairly chilly Thanksgiving day. Highs 6 to 9 degrees below normal. This forecast was a 50 50 blend of the 12z/22 GFS/NAM MOS. && .LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/... Fairly quiet weather is expected for most of the extended period through next Tuesday, with a chance of isolated showers this weekend. High pressure is forecast to build across the area Thursday night into Friday and bring dry weather to the region. Temperatures are forecast to be near or slightly below normal Thursday, before warming back to near or slightly above normal Friday. The high builds offshore Friday night in advance of an approaching cold front coming through the area Saturday. Also, an area of low pressure is forecast to be moving northeastward offshore of the Mid- Atlantic coast on Saturday. This low is currently expected to remain far enough offshore to not bring major effects to the area Saturday. However, as the front moves through Saturday there is a chance of isolated/scattered showers across the area. For Saturday night into Sunday, the low moves farther to our northeast with high pressure to our west. This will keep a strong northwest flow across the area Saturday night and Sunday. It is possible that some isolated lake effect showers could make their way across our area Saturday night into Sunday in the northwest flow. Temperatures remain above normal Saturday before the front moves through the area, but falls back to near normal or slightly below for Sunday. By Sunday night, high pressure begins to approach from the west and the flow turns more northerly, cutting off the lake effect showers potential across our area. The high pressure fully builds across the area Monday, then pushes offshore by Tuesday. This will bring dry weather back to the area early next week. Temperatures are expected to be near normal or slightly below for Monday, then warm back to above normal Tuesday as return flow develops. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas. This afternoon..VFR sct-bkn clouds aoa 4000 ft. Northwest wind gusts 25-30 kt. Tonight...VFR clear with northwest wind gusts diminishing. Confidence high. Thursday...VFR clear or some high clouds at times. Northwest to west wind with gusts under 15 kt. Confidence high. OUTLOOK... Thursday night-Friday night...VFR expected. Westerly winds Thursday- early Friday. Becoming southwest later Friday into Friday night. High confidence. Saturday-Sunday...Generally VFR. Isolated showers possible which may occasionally lower conditions. Southwest winds early Saturday, becoming northwest and gusting 20-25 knots Saturday night into Sunday. Moderate confidence on showers and sub-VFR conditions, high confidence on winds. && .MARINE... SCA continues as previously advertised. Gusts near 30 kt later this afternoon. Will discuss in more detail at 230 PM the diminishing wind and advisory sitn for Thursday. OUTLOOK... Thursday night-Saturday...Sub Small Craft Advisory conditions expected, although seas may be around 4 feet Thursday before subsiding. Saturday night-Sunday...Small Craft Advisory conditions likely behind cold frontal passage. && .EQUIPMENT... The KDOX radar remains out of service. Replacement parts are expected to arrive today. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...None. NJ...None. DE...None. MD...None. MARINE...Small Craft Advisory until 6 AM EST Thursday for ANZ450>455. Small Craft Advisory until midnight EST tonight for ANZ430-431. && $$ Synopsis...Drag/Robertson Near Term...Drag 1216 Short Term...Drag 1216 Long Term...Robertson Aviation...Drag/Robertson 1216 Marine...Drag/Robertson 1216 Equipment... is the U.S. government's official web portal to all federal, state and local government web resources and services.