502 FXUS61 KPHI 300121 AFDPHI Area Forecast Discussion National Weather Service Mount Holly NJ 921 PM EDT Fri Mar 29 2019 .SYNOPSIS... High pressure remains anchored over the western Atlantic while a cold front continues to slowly approach from the west. That front finally makes its way across the region late Saturday night through Sunday. High pressure returns for the start of the new work week, then moves offshore by the middle of the week. Coastal low pressure passes east of the Delaware and New Jersey coasts on Wednesday. Another frontal system may affect the area late next week. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... Little updates made to the forecast this evening, only some minor changes to PoPs and temperatures/dewpoints based on current trends. Generally expect mid-high level cloud cover to keep overnight mins a bit above normal across the area (generally mid to upper 40s with a few warmer spots not getting out of the 50s). Can't rule out some drizzle or patchy fog in the Poconos/NW NJ given near-saturated low-lvls, but don't have enough confidence to add to forecast at this time (and impacts should be limited if it does occur). && .SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/... Saturday is expected to be mostly dry across much of the area. The front to our north, while another cold front begins moving across far western Pennsylvania during the day. Most places will just experience partly to mostly clouds skies with mid-high level clouds in place. Our area will be under the influence of a tight pressure gradient between an area of low pressure moving along the frontal boundaries to our northwest, and high pressure to our northeast. This will keep an increasing flow across the are, shifting from the south-southeast to the south-southwest during the day. Winds will likely become gusty during the afternoon with gusts reaching 20-25 mph at times for many areas. Temperatures will be well above normal across the area, reaching 10-15 degrees above normal. && .LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/... Cold front slowly works its way east through the Ohio Valley, and then through western New York and western Pennsylvania Saturday evening, before arriving just west of the Delaware and Lehigh Valleys by daybreak Sunday. At least the first half of Saturday night should be dry, and then showers begin to move into far western portions, generally the southern Poconos and Lehigh Valley, before daybreak Sunday. Showers then continue across the region Sunday morning, tapering off late in the day, as the cold front works its way east. Not much rainfall is expected, generally on the order of 1/10 to 1/4 inch QPF. Although cooler than Saturday with highs in the 50s to low 60s, the much cooler air will not arrive until Sunday night/Monday. Lows Sunday night will be in the 20s and 30s, then highs on Monday will be in the 40s. Dry conditions on tap for the start of the new week as high pressure builds in from the west, then moves offshore on Tuesday. Models still showing the development of a coastal low for the mid-week period. However, there is little consistency among the models in terms of timing, strength, and placement of the low. The ECMWF is the closest, bringing rain along the coasts Tuesday night through Wednesday. The GFS is a bit farther east, and has little precip except for the immediate coastal areas. The CMC is far offshore with no significant direct impacts. It is still fairly far out, so will blend the NBM/Superblend guidance for PoPs, which has the highest along the immediate Delaware and southeast New Jersey coasts. High pressure then builds across the region on Thursday before moving offshore, and then another frontal system may impact the region to close out the work week. && .AVIATION /01Z SATURDAY THROUGH WEDNESDAY/... The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas. Tonight...Mostly VFR conditions are expected across the TAF sites for tonight. The exceptions if a brief period late this afternoon/early this evening when a period of showers is possible for ABE/RDG which may temporarily lower ceilings and/or visibilities to MVFR. After this, VFR conditions will continue through the overnight. Winds late this afternoon will remain from the south-southwest around 5-10 knots or less, then become light and variable later this evening and overnight. Saturday...VFR conditions expected. Winds will increase during the morning out of the south-southeast around 5-10 knots, then increase more out of the south-southwest during the afternoon to 10-15 knots with gusts 20-25 knots possible. Outlook... Saturday night through Sunday...MVFR/IFR conditions in rain showers. Improvements late Sunday. South winds around 10 kt Saturday night become west-northwest Sunday afternoon at 15 kt with 20-25 kt gusts. Sunday night through Monday night...VFR. NW winds 10-15 kt with gusts up to 20 kt. Tuesday...Afternoon showers possible. Wednesday...Scattered showers possible, mainly at KACY. Low confidence. && .MARINE... Tonight...Conditions expected to remain below advisory levels tonight, although seas will remain 3-4 feet and may occasionally approach 5 feet. Saturday...Conditions expected to start the day below advisory levels, however, winds and particularly seas will increase through the day, likely reaching advisory levels during the afternoon. Therefore a Small Craft Advisory has been issued starting at 2 pm for the Atlantic Ocean coastal waters. Outlook... Saturday night through Sunday night...SCA conditions, though a lull is possible Sunday afternoon. South winds 15-20 kt with gusts up to 25 kt Saturday night will become NW 15-20 with gusts up to 25 kt Sunday afternoon and night. VSBY restrictions in rain showers, mainly on Sunday. Monday...Lingering SCA conditions possible. Tuesday...Sub-SCA conditions expected. Wednesday...SCA conditions possible. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...None. NJ...None. DE...None. MD...None. MARINE...Small Craft Advisory from 2 PM Saturday to 6 AM EDT Sunday for ANZ450>455. && $$ Synopsis...MPS Near Term...Carr Short Term...Robertson Long Term...MPS Aviation...Robertson/MPS Marine...Robertson/MPS