Area Forecast Discussion
Issued by NWS Mt. Holly, NJ
Issued by NWS Mt. Holly, NJ
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852 FXUS61 KPHI 041745 AFDPHI Area Forecast Discussion National Weather Service Mount Holly NJ Issued by National Weather Service Baltimore MD/Washington DC 1245 PM EST Wed Nov 4 2026 .WHAT HAS CHANGED... Aviation section updated with 18Z TAFs. && .KEY MESSAGES... 1. No significant weather through today. 2. A slow moving cold front approaches the area Thursday night into Friday bringing the potential for heavy rain to portions of the area. && .DISCUSSION... KEY MESSAGE 1...No significant weather through today. An expansive area of high pressure offshore is in control, resulting in warm south/southwesterly flow and tranquil weather. A stretch of nice mid-Fall days will continue through the middle of the week. With some weak moisture advection, mostly clear skies, and light winds tonight, patchy fog across the area this morning has cleared. Warm temperatures in the 70s are expected again today. KEY MESSAGE 2...A slow moving cold front approaches the area Thursday night into Friday bringing the potential for heavy rain to portions of the area. Upper level ridging will finally begin to break down by Thursday as a potent upper trough over the central CONUS cuts off and lifts northeast into the Great Lakes region by Friday. This upper level low is then forecast to slowly move east toward New England over the weekend. At the surface, low pressure over the Central Plains will lift north into the northern Great Lakes by Wednesday and up into Quebec/Ontario on Thursday. Its associated cold front will trail back to the southwest but will begin to slow down in forward progression as it tracks toward the region before eventually stalling somewhere over/offshore of the Mid-Atlantic late Thursday. The biggest question that remains at this time is where exactly and in what orientation does the front stall/wash out, as this will play a major factor on how things pan out later Thursday and Friday. Given the latest RRFS and ensemble guidance it is becoming increasingly likely that the front will stall out within close vicinity to our area. Guidance is then keen on developing a surface low along the boundary late Thursday night and into Friday while tracking northeast along the stalled boundary before lifting up into New England on Saturday and pulling the front offshore. All in all, this will yield the potential for some showers and light rain to begin on Thursday for western areas as the front approaches. But as the front weakens, the forcing will too, meaning that many areas will stay mainly dry on Thursday as PoPs are generally less than 30% along and southeast of the I-95 corridor. This changes by Thursday night and into Friday, as a higher plume of PWATs will surge northward upwards of 1.5-1.7 inches, which would push close to the climatological max for early November. While not currently outlooked by WPC in the Excessive Rainfall Outlook, it is in the realm of possibility that areas of heavy rain may occur from time to time late Thursday night into Friday. The greatest potential of this threat and where there may be a localized maxima of higher QPF is targeted to be south and east of the I-95 corridor at this point in time. However, it should be noted that this is highly uncertain and dependent on the placement of the stalled front. To summarize, a slower front will yield more rainfall across the region, in comparison to a faster front which will yield less rainfall across the region. Rain chances should then decrease heading into the weekend as surface high pressure attempts to build in from the west. However, as the upper low meanders across the Northeast, this is highly dependent on how lobes of shortwave energy evolve. Thus, while it has trended drier over the weekend, there is quite a bit of uncertainty. The takeaway message here is that the weekend may not be fully dry and could remain somewhat unsettled into early next week with some diurnal opportunities for showers. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/... The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas. Wednesday...South/southwest winds 5 to 10 kt. High confidence. Wednesday night...VFR. A slight chance of showers near KRDG. Patchy fog possible. Winds generally light and variable. Moderate confidence. Outlook... Thursday through Saturday...Periods of sub-VFR conditions likely, especially Thursday night into Friday. Periods of rain expected with a slight chance of a thunderstorm. Terminals near the coast will maintain VFR conditions. Wind gusts 15 to 20 knots are expected across the terminals Thursday morning and into the afternoon, before diminishing after sunset. Saturday night through Sunday...VFR. No significant weather expected. && .MARINE... Tranquil conditions expected on the waters through tonight with southerly winds around 10 kt and seas 1 to 2 feet. Outlook... Thursday...No marine headlines expected. Winds will generally remain less than 20 kt with seas of 2-4 feet. Fair weather. Thursday night through Sunday...Periods of SCA conditions possible. While winds will largely remain less than 25 kt, seas are expected to range between 3-5 feet. Periods of rain likely through Saturday. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...None. NJ...None. DE...None. MD...None. MARINE...None. && $$ DISCUSSION...MJL/WFO PHI AVIATION...MJL/WFO PHI MARINE...MJL/WFO PHI