Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000 FXUS61 KPHI 290409 AFDPHI Area Forecast Discussion National Weather Service Mount Holly NJ 1209 AM EDT MON AUG 29 2016 .SYNOPSIS...
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A weak frontal boundary over western New York State will slide down into our area later today, then slowly dissipate on Tuesday. Tropical Depression Eight is anticipated to pass well to our southeast of our area on Wednesday as a strong cold front nears our region from the northwest. The front is expected to pass through eastern Pennsylvania, New Jersey, northeastern Maryland and Delaware early on Thursday followed by high pressure for Friday, Saturday and Sunday.
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&& .NEAR TERM /UNTIL 6 AM THIS MORNING/... Primary concerns this evening are chances for precip across the Poconos and the development of fog. In terms of precip, thunderstorms to our west will struggle to make it east into our County Warning Area. Sufficient moisture, lift, and instability are lacking. However, we have noticed some mid-level clouds develop across the Poconos, where there is weak low-level convergence and resultant moisture pooling. Some of the high res guidance, mainly the HRRR, bring some very light precip into Carbon and Monroe Counties, which the 12Z Euro also hints at. For now, we have brought slight chance POPS into the aforementioned areas between 02Z and 06Z, for sprinkles. Given the lack of instability, no thunder is anticipated. Patchy dense fog is also possible again tonight, but should be confined further south into Delmarva, as cloud cover streams into the Poconos, portions of the Lehigh Valley and northern New Jersey. Nevertheless, some of the typically prone locations may fog a bit, prior to the thicker cloud cover moving in. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TUESDAY/... The cold front starts to make its way into our area on Monday morning. However, there seems to be very limited moisture associated with the front. Not expecting much in the way of showers across the region and only mention an isolated shower or thunderstorm for the late afternoon time frame. Temperatures will again be similar to the weekend, with highs into the mid to upper 80s to around 90 across the region. Shore points will be slightly cooler and remain closer to the lower 80s. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... A weak short wave trough traveling in the mid level flow is forecast to pass over the northeastern states on Tuesday. The feature will bring additional drying to to region. As a result, we are anticipating a mostly sunny sky on Tuesday. High temperatures should approach 90 degrees except in the elevated terrain and right along the coast where readings will likely not get above the lower and middle 80s. It appears as though Tropical Depression Eight will remain well enough to our southeast on Wednesday as not to impact our land areas. Meanwhile, a cold front is forecast to approach from the northwest. Temperatures will remain quite warm ahead of the front. Highs on Wednesday should be similar to those expected for Tuesday. We will mention a chance of afternoon showers and thunderstorms from the Interstate 95 corridor northwestward in the developing lift in advance of the cold front. The chance for showers and thunderstorms will overspread the remainder of our forecast area on Wednesday night with some lingering precipitation possible near the coast into Thursday morning. The front is expected to work its way though our region early in the day with the wind shifting to the northwest. Maximum temperatures on Thursday are anticipated to be in the 70s in the elevated terrain of the Poconos and northwestern New Jersey and in the 80s elsewhere. Dew point readings should drop into the lower 60s and 50s. High pressure is forecast to build from Ontario and the Great Lakes on Thursday to the northeastern states on Saturday before drifting off the coast. The air mass will be noticeably cooler and less humid than the one that it will be replacing. && .AVIATION /04Z MONDAY THROUGH FRIDAY/... The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas. Tonight...Predominantly VFR conditions expected. Some patchy fog is possible once again overnight, particularly at TTN, RDG, ACY, and MIV, which may result in brief MVFR/IFR restrictions late. Monday...Predominantly VFR conditions. Light west to southwest winds around 10 knots or less will veer to the northwest late in the afternoon, generally north of ILG, ACY, and MIV. An isolated shower or thunderstorm is possible during the afternoon/evening. OUTLOOK... Monday night through Wednesday morning...Mainly VFR. Late night and early morning visibility restrictions are possible. Wednesday afternoon into Wednesday night...Mainly VFR. However, there is a chance of showers and thunderstorm. Thursday through Friday...Mainly VFR. && .MARINE... Sub-advisory conditions continue on the area waters through Monday. Easterly winds tonight will veer to the west across the New Jersey waters, but an easterly component will remain across the Delaware waters. Seas will remain around 2 to 4 feet. OUTLOOK... Monday night through Friday...No marine headlines are anticipated. However, long period swells may create rough conditions in and around the inlets along the coasts of New Jersey and Delaware. RIP CURRENTS... The much anticipated long period swells from Tropical Cyclone Gaston have arrived this evening. These 12 to 15 second swells, combined with waves in the surf zone around 3 feet, will lead to a moderate risk for the formation of dangerous rip currents for Monday along the NJ shore and Delaware beaches. Looking ahead, the long period 12 to 15 second swells are forecast to become more pronounced along the coasts of New Jersey and Delaware on into Tuesday. We continue to expect an enhanced threat for the development of dangerous rip currents for much of the week, and in particular on Tuesday, due to onshore winds. In terms of safety, follow the advice of local lifeguards who will be observing. This is not a time to swim on your own without lifeguard presence. Additionally, waders are cautioned not to turn their backs to the waves when coming out of the water. Wave knock down can result in upper torso injury. && .CLIMATE...
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This section is up to date through 1205 AM Today-Monday August 29. A top 4 warmest August appears assured most of our forecast area with record monthly warmth likely at PHL. A top 3 warmest June-July-August for Philadelphia, Allentown and possibly Atlantic City. Philadelphia is on its way for its warmest August on record (dating back to 1874). More than 4 degrees above normal. This Philadelphia August ranking includes our forecast temps (SFT specific values) through the 31st. The 30 year normal is 76.6 Records date back to 1874. 1. ~81.0 2016 2. 79.9 1980 3. 79.8 2001 and 1995 Regarding whether August can tie its record of 17 90F days. Its possible but not probable. Foresee an additional 3 to 4 more 90 degree days to add onto the 13 we have so far this month. The record of 17 was set in 1995. The mean for the month is only 5. Allentown will probably rank #2 warmest August. Records date back to 1922. Normal is 71.7 and we are projecting a positive departure of around 5 degrees. 1. 78.2 1980 2. 76.6 2016 3. 76.0 1937 Atlantic City records date back to 1874. The August monthly normal is 74.4 and we`re projecting a positive departure of nearly 4 degrees. As it stands, Atlantic City will rank #1 or #2 warmest August with very little chance of slipping to #3. The forecast and climate for Atlantic City has greater variability than Allentown and Philadelphia due to proximity to water on sea breeze days and notable radiational cooling on some nights. 1. 78.2 2016 2. 77.9 2005 3. 77.1 2009 Seasonal: This summer 2016 for Philadelphia will probably be the 2nd warmest June-July-August (JJA) in the period of record dating back to 1874. 1. 79.6 2010 2. 78.8 2016 3. 78.6 1995 4. 78.3 1994 Allentown seasonal avg is projecting 75.0 or a ranking of around #2 in the por. 1 75.3 1949 2 75.0 2016 3 74.6 2005 and 1980 Atlantic City seasonal average is projecting 75.8...4th warmest in the por. 1. 77.5 2010 2. 77.0 2011 3. 75.9 2005 4. 75.8 2016 5. 75.5 2008 90 degree days through the 28th. season mean Aug Aug Aug Season mean rer rer abe 33 17 12 4 16-1980 41-1966 acy 27 10 10 3 11-2010 46-2010 phl 38 21 14 5 17-1995 55-2010 ilg 32 20 13 5 23-1895 59-1895 Rainfall: Considerable uncertainty exists regarding additional rainfall in August, so this part of the climate is stated with caution. Presuming no further measurable rain this month of August...the current ACY value of 1.10 would rank the 6th driest August on record, after a 6th wettest July. For Philadelphia, the June-August seasonal total of 7.45 inches is so far, the 12th driest summer...again this presumes no further measurable rain in August.
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&& .PHI WATCHES/WARNINGS/ADVISORIES... PA...None. NJ...None. DE...None. MD...None. MARINE...None. && $$ Synopsis...Franck/Iovino 1209AM Near Term...Franck/Meola Short Term...Franck/Meola Long Term...Iovino Aviation...Franck/Iovino/Meola Marine...Franck/Iovino/Meola Climate...1209AM is the U.S. government's official web portal to all federal, state and local government web resources and services.