521 FXUS61 KPHI 291346 AFDPHI Area Forecast Discussion National Weather Service Mount Holly NJ 946 AM EDT Thu Aug 29 2019 .SYNOPSIS... High pressure will build eastward across the Mid-Atlantic through Friday before another weak cold front passes overhead Friday night. High pressure looks to return for Saturday and Sunday before the next cold front grazes the area by late Monday. Low pressure then looks to track across eastern Canada next Tuesday into Wednesday dragging another cold front through the area around the midweek time frame. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... Warmed temperatures slightly and adjusted dew points according to observations. Otherwise, no significant changes with the 9:30 am update. Surface high pressure located over the Tennessee Valley this morning will build to the east/northeast. As the high builds towards our area, the front that crossed the region overnight will push offshore and take the weakening TD Erin with it, away from our area. With the two systems close to the area, the pressure gradient tightens up for a bit through the day today and we will the northwest winds become gusty, mainly this afternoon, before subsiding towards sunset. Conditions today will be much drier and, as a result, much less humid as the dry air aloft mixes down more efficiently through the day. It will feel nice and comfortable today as the dew points down down in the 50s across the region. Even with warming occurring at the surface, the dry air aloft may be enough to keep cloud development from taking place, with only a few or scattered mid level decks possible. Even with some clouds around, we will see plenty of sunshine across the forecast area. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/... The gradient relaxes as the front/TD Erin quickly move off to the northeast and the high starts to dominate across the Mid-Atlantic. The winds should really diminish quickly after sunset and with skies remaining clear overnight, we will radiate quite efficiently. Lowered temps a bit below guidance in the more prone spots of the Pine Barrens in NJ as temps tend to drop much quicker there than most models can anticipate. Overnight lows will be in the 50s through much of the region with some lower 60s through the I-95 corridor, along the immediate coast and across Delmarva. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... Dry weather Friday and Saturday as high pressure builds across the Mid-Atlantic behind the cold frontal passage Thursday. Warm and pleasant Friday with highs in the mid to upper 80s ahead of a weak cold front. Moisture will be very limited so we removed mentionable PoPs. Temperatures don't drop a whole lot behind the front with highs in the low 80s Saturday along with low humidity. Chances for some scattered showers/storms return by Sunday afternoon as the high moves off to the northeast while some shortwave energy arrives from the west. However instability looks limited at this point so activity should be isolated to scattered in nature with best chances looking to be N/W of the I-95 corridor. Better chances for thunderstorms Monday afternoon and evening with a secondary short-wave as CAPE values actually may approach 1000 J/kg. Timing will be important, though, with stronger storms forming near and after peak heating. Highs look to top out in the upper 70s to low 80s Sunday with temperatures generally warming a few degrees into Monday. The progressive patterns continues into Tuesday and Wednesday of next week. At this point Tuesday looks to be mainly dry before the next cold front arrives by later Wednesday bringing chances for showers and storms. We will also need to pay attention to what transpires with now Hurricane Dorian. At this time, it is not expected to directly impact our area, but tropical moisture and rains could affect our area if it tracks up the Eastern Seaboard next week after making landfall. It is too soon to tell, though. Highs will be on the upswing, however, with mid to upper 80s being possible for start of meteorological fall! && .AVIATION /14Z THURSDAY THROUGH MONDAY/... The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas. Today...VFR conditions expected. Northwest winds around 10 knots with gusts around 20 knots through this afternoon. Tonight...VFR conditions expected. Northwest winds will drop off this evening and become light and variable overnight. Outlook... Friday...VFR conditions expected. West to southwest winds around 5 to 10 knots. Saturday...VFR conditions expected. North to northeast winds around 5 to 10 knots. Sunday...Mainly VFR conditions expected. MVFR or lower possible in showers and thunderstorms. East to southeast winds around 5 to 10 knots. Monday...Mainly VFR, though lower restrictions possible in showers and thunderstorms. Southeast winds 5 to 10 knots turning southerly in the afternoon. && .MARINE... Northwest winds around 10 to 15 knots with gusts around 20 knots. Seas 2 to 4 feet. With TD Erin moving closer to the area and then quickly off to the northeast through tonight, there is the possibility we could see seas increase and approach 5 feet later today, especially along the easternmost portions of the ocean zones. The tighter pressure gradient could lead to some gusts around 25 knots. However, it continues to look like a marginal situation and may be more intermittent than consistent so we have decided to hold off on any headlines at this time. Outlook... Friday...West to southwest winds around 10 to 15 knots with gusts up to 20 knots. Seas 1 to 3 feet. Saturday...North to northeast winds around 10-15 knots, veering easterly late in the day. Seas 1 to 3 feet. Sunday...East winds around 10 to 15 knots. Seas 1 to 3 feet building to 2 to 4 feet through the day. Monday...Sub-SCA conditions expected with southeast winds around 10 knots. Seas 2 to 4 feet. Rip Currents... There will be a moderate risk for the development of dangerous rip currents today. Although the winds will be offshore (from the west- northwest), seas 3-4 ft and a somewhat long period (around 9 seconds) SE swell will keep the risk at moderate for at least one more day. && .TIDES/COASTAL FLOODING... The combination of a prolonged easterly flow and the approaching new moon on Friday is resulting in higher than normal high tides. Areas of minor tidal flooding may occur once again with Thursday evening's high tide. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...None. NJ...None. DE...None. MD...None. MARINE...None. && $$ Synopsis...Davis/Fitzsimmons Near Term...Davis/Meola Short Term...Meola Long Term...Davis/Fitzsimmons Aviation...Fitzsimmons/Meola Marine...Fitzsimmons/Meola Tides/Coastal Flooding...