291 FXUS61 KPHI 230014 AFDPHI Area Forecast Discussion National Weather Service Mount Holly NJ 814 PM EDT Fri Mar 22 2019 .SYNOPSIS... The coastal storm which has been impacting the region will continue to pull away tonight. A cold front will also move through tonight, with gusty northwest winds continuing through Saturday. High pressure will bring dry and mild weather on Sunday. A cold front will move through Monday with showers possible. A large high pressure center will bring dry but cool weather for the middle part of next week. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... The areal coverage of the showers is decreasing now and the rain/graupel showers are mostly passing offshore. Lingering activity through 11pm or so will be covered by small chc pops or slgt chc pops in the fcst. Snow showers will be possible in the late overnight across the srn Poconos. Gusty W to NW winds will continue as the deep low well offshore continues to move away. Only minor adjustments were made to temps/winds for the evening updates. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/... The low over the Canadian Maritimes finally lifts away late Saturday, and high pressure will build in from the west. Dry conditions on tap, but gusty northwest winds continue, until finally subsiding late. Sunny with highs in the 40s to low 50s, except in the 30s in the southern Poconos. && .LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/... Summary...a fairly quiet extended forecast across the area, with the exception of a strong cold frontal passage Monday night. A shortwave trough will move toward the region, driving a weak surface low to move across the central U.S. toward the mid- Atlantic along a cold front. This shortwave will reinforce the longwave trough to our northeast as it does so, thus ushering in colder air. High pressure will build across the Great Lakes into the region Tuesday. By Thursday, the high will move off the coast, leading to milder return flow as we close out the workweek. More rain is possible as we head into Friday as a cold front approaches from the northwest. There is some indication that an area of low pressure may develop off the Southeast Coast by Friday, however this remains uncertain and will need to continue to be monitored. Dailies... Saturday night and Sunday...quiet with temperatures near normal. Lows Saturday in the mid 20s north to the low 30s across southern Delware. Highs recover to seasonable values as southwesterly flow develops ahead of the next cold front. Most locations will top out in the mid to upper 50s. Sunday night and Monday...precipitation overspreads the region by early Monday morning. Mild temperatures continue with lows staying in the 40s for the most part. Highs will range from the mid 40s across the southern Poconos to the low 60s across southern Delaware. Precip looks to stay all rain during the day Monday, though a changeover to snow may begin by evening across the southern Poconos. Monday night and Tuesday...precip continues across the region as the cold front continues to advance southward. As the freezing line makes its way southward, rain will transition to a mix of rain and snow, eventually transitioning to all snow. It is still a little unclear how far south this will occur, but at this point, it looks as if temperatures will cool enough before precip moves out the area for some snow showers to make their way into the greater Philadelphia Metro. Any accumulation would be very light, though it is still too far out to discuss totals at this point. Precip should move out the area by Tuesday afternoon as skies begin to clear. However, it will be much cooler Tuesday with highs only making it into low 40s for much of the area. Tuesday night through Friday night...A relatively quiet period overall. Cold Tuesday night with lows dropping below freezing across the area, even into the teens across the southern Poconos. Highs gradually moderating Wednesday through Friday, as high pressure works its way from the Great Lakes to the western Atlantic; many locations look to make it into the upper 50s to near 60 by Friday. Uncertainty in the exact timing of rain Friday and Friday night, as a cold front makes its way toward the mid-Atlantic, while a wave of low pressure rides along the stalled cold front to our south from earlier in the workweek. Went with a blended approach for now, including only a slight chance for showers early Saturday morning.&& .AVIATION /20Z FRIDAY THROUGH WEDNESDAY/... The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas. Tonight...Lingering shower activity should dissipate soon after 0z. Generally VFR, although occasional MVFR ceilings possible at RDG and ABE and cannot rule out a passing snow shower at those sites through midnight. WNW winds remain elevated at 15 to 20 kt with gusts up to 35 kt. Saturday...VFR. NW winds still around 15 to 20 kt with gusts to 35 kt. By mid to late afternoon, winds should start to diminish with gusts falling below 30 kt. OUTLOOK... Saturday night-Sunday night...VFR, except MVFR possible late Sunday night. WNW winds Saturday night will become westerly then southwesterly on Sunday and through Sunday night. Lingering gusts of 20 to 25 kt possible early Saturday night, otherwise speeds 5 to 10 kt. Monday-Monday night...MVFR and possibly IFR Monday with rain showers. Winds shifting from southwesterly to westerly to northerly on Monday with speeds 5 to 10 kt. VFR by Monday night with winds northerly or northeasterly at around 10 kt with gusts to 20 kt. Tuesday-Wednesday...VFR. Northeast winds 5 to 10 kt becoming easterly at 5 to 10 kt on Wednesday. Gusts to 20 kt possible Tuesday morning. && .MARINE... A Gale Warning remains in effect for all waters. Northwest winds 20-30 kt with gusts up to 45 kt gusts through tonight. Showers early. Saturday...Northwesterly gales continue for much of this period, but wind speeds should gradually drop off late Saturday into Saturday night. Outlook... Sunday through Monday...sub SCA conditions with northwesterly winds of 10 to 15 knots. Some higher gusts possible Sunday and Monday afternoon of 15 to 20 knots. Wave heights of 1 to 3 feet. Tuesday...SCA conditions possible with northerly winds 20 to 25 knots, with gusts of 25 to 30 knots possible. Waves of 4-7 feet possible. Wednesday through Friday...sub SCA conditions with northerly winds of 10 to 15 knots Wednesday turning more southeasterly by Friday with speeds dropping to 5 to 10 knots. Waves generally 2 to 4 feet. && .HYDROLOGY... Much of the precipitation is winding down across the area. It has been more showery this evening with some graupel mixed in. Many of the gages that were rising earlier today have crested and are now falling. The exceptions are: The gage at Pemberton on the North Branch Rancocas is expected to remain below Flood Stage, but slowly rise towards Actions stage tomorrow. The gage at Blackwells Mills on the Millstone River will climb above Action Stage late tonight, but is forecast to remain below Flood Stage. It will begin falling by Saturday morning. The gage at Pine Brook on the Passaic River will climb above Action Stage shortly and then continue to slowly climb to near Flood Stage Saturday night or Sunday morning. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...None. NJ...None. DE...None. MD...None. MARINE...Gale Warning until 6 PM EDT Saturday for ANZ430-431-450>455. && $$ Synopsis...O'Brien Near Term...O'Hara Short Term...Franklin Long Term...Davis Aviation...Franklin/O'Brien/PO Marine...Davis/Franklin Hydrology...RK/PO