607 FXUS61 KPHI 251943 AFDPHIArea Forecast Discussion National Weather Service Mount Holly NJ 343 PM EDT Thu Sep 25 2025
.SYNOPSIS... A warm front has moved north of the area. Behind it, a cold front is expected to move through tonight. This front then lingers off the coast into the beginning of the weekend. Broad high pressure will then approach from the west on Sunday into early next week.
&&
.NEAR TERM /THROUGH FRIDAY/... into the evening... A cold front will approach from the west this evening. Showers and scattered tstms are expected to form in our area once the front gets closer. We`ll continue with the likely/categorical pops for the area into the evening. Severe weather remain possible with some damaging winds, but the threat is marginal at best. South to Southwest winds 10 to 15 mph expected.
Tonight, unsettled much of the night with rains/tstms during the evening and the more scattered activity overnight. A weak wave will try to form along the cold front any may bring more frequent showers S/E after midnight. Low tonight will fall into the 60s and it;ll remain humid overnight. Rainfall will spotty and locally heavy. Average rains 1/2 to 3/4 inch S/E to 1.0 to 1.5 inches N/W.
On Friday, the surface high well to the west will begin to ridge across the area. An upper trough will still linger across NY/PA however. Drier air will arrive for the morning across the western areas and then spread east thru the day. We`ll continue with some clouds/fog early then becoming partly sunny for the afternoon. A couple showers across the S/E areas are possible during the morning but pops are only 20% to 30%. It`ll remain seasonably warm with highs climbing into the upper 70s/low 80s across the area.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/... For Friday night and the weekend, a weak surface trough will be located just to the south offshore. This will lead to the potential for some light showers, most concentrated across DelMarVa and southern NJ but heavy rainfall is not currently anticipated. Showers look to be more scattered during the daytime on Saturday (20-40% chance) before becoming a bit more widespread Saturday night (45-65% chance). Highs in the mid 70s expected with lows in the upper 50s to mid 60s.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/... Heading into the workweek, a broad upper ridge will be located over the central US with at least one low pressure system well offshore. NHC is continuing to monitor now Tropical Storm Humberto, along with a second potential invest area for tropical cyclone development. Given the temporal range of the forecasts, we dont currently know much what the impacts or details of the tracks will be. NHC`s message regarding these two systems remains that "the steering scenario for the tropical cyclone will likely become more complicated due to the interaction with the developing system 94L to the west" and as a result "there is lower than normal confidence in this forecast track". Given the significant uncertainty, the forecast will keep with a persistence forecast with modest 20-40% chances of rain for Sunday-Tuesday and a general lowering of temperatures trend through the middle of the week. We`ll continue to monitor the systems for any potential impacts and adjust the forecasts as confidence increases in at least some viable solution.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/... The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas...
thru Sunset... Scattered showers will become more numerous as we heads towards 21Z/22Z. Tstms may develop into a line and move SW to NE across the terminals late this afternoon. We`ve included tempo groups in the TAFs to highlight this occurrence. Mostly MVFR conditions expected, but IFR in rains and tstms expected. South to Southwest winds around 10 to 15 knots. Medium confid overall.
Tonight... A band of showers and scattered tstms will be crossing thru the Delaware Valley around sunset and will continue east to KMIV/KACY shortly thereafter. Following it, rains will linger into the overnight for KMIV/KACY by taper off for the N/W sites (KRDG/KABE). Fog can be expected most areas, but perhaps become dense and persist longer where some limited clearing happens after midnight (NW sites). Winds become West to Northwest and remain 5 to 10 knots. Medium/Low confid/
Friday... There will likely be some lingering low clouds and fog past 12Z at many TAF sites. After that however, VFR is expected to return by mid-morning and remain for the remainder of the day. West to Northwest winds will increase to around 10 knots by afternoon. Medium confid.
Outlook... Friday night through Tuesday...VFR conditions developing later Friday. A chance of showers (35-45%) will continue through Monday, presenting an opportunity for additional periods of sub-VFR conditions.
&&
.MARINE... Winds and seas will increase late this afternoon for a short period prior to the front crossing the waters. It doesn`t appear to persist long enough to put up SCA flags however. There will be scattered tstms too with localized higher winds and seas. South winds around 15/17 kts with gusts 20 to 22 knots mostly. Seas will build to around 4 ft overall.
Winds and seas will settle late tonight with frequent showers expected. Winds will become West to Northwest around 10 knots on Friday.
Outlook... Friday night through Monday...No marine headlines currently expected. A chance of showers each day (around 20% Friday night, 60% on Saturday, 30-40% on Sunday and Monday). A small chance (20% or less) embedded thunderstorms possible each day.
Rip Currents...
For Friday...kept the MODERATE risk all beaches. The wind pattern behind the departing low looks to bring winds mostly offshore and rather light for much of of the day. Swell continue to lower as offshore storms move further away from our waters.
For Saturday...went with a LOW risk all beaches. While winds turn northeast to east around 10 mph, wave heights offshore continue to diminish and swell from storms well offshore continues to dwindle for the time being.
For specific beach forecasts, visit weather.gov/beach/phi
&&
.PHI WATCHES/WARNINGS/ADVISORIES... PA...None. NJ...None. DE...None. MD...None. MARINE...None.
&&
$$
SYNOPSIS...AKL/OHara NEAR TERM...OHara SHORT TERM...AKL LONG TERM...AKL AVIATION...AKL/OHara MARINE...AKL/OHara
NWS PHI Office Area Forecast Discussion