FXUS61 KPHI 250806 AFDPHI Area Forecast Discussion National Weather Service Mount Holly NJ 306 AM EST Thu Dec 25 2025 .SYNOPSIS... A weak clipper system will track through the area on Christmas Day. High pressure will build again briefly into Friday morning. A low pressure system will bring widespread wintry precipitation to the region late Friday into early Saturday. Another system will impact the region late Sunday. Cold and dry high pressure will build and persist through Tuesday. Another weak clipper system is possible next Wednesday. && .NEAR TERM /THROUGH TONIGHT/... Lake enhanced clouds and flurries continued to stream in across the region this evening as brisk northwest winds become gusty during the day. Temps will be fairly seasonably across the region with highs generally in the mid 40s until cold air advection ramps up behind a cold front that will back through the region. That cold air will also bring a drier airmass in overnight allowing temps to cool for Christmas evening into the teens for most of central and norther NJ along with the Poconos and Lehigh Valley. The high pressure that builds behind the cold front for the afternoon and overnight hours will be short lived however as a stronger system sets up to the west. For Christmas night: The cold front will usher in a colder and drier airmass. Temperatures are expected to fall into the 10s near and north of I-78, and into the low to mid 20s south of I-78 by Friday morning. Skies will be partly cloudy. Winds relatively light, so wind chill won't be much of a factor. && .SHORT TERM /FRIDAY THROUGH SATURDAY/... A winter storm is expected to impact the region on Friday and Friday Night, bringing impacts to the entire region in some form. Winter Storm Watches remain in effect from the Philadelphia metropolitan area on north. Details to follow... Canadian high pressure will be situated off to the north to start the day, locking in some low-level cold air over most of the region. Low pressure comes out of the Great Lakes and dives southeast across the Applachians, moving offshore of the Mid-Atlantic by Saturday morning. As the surface low moves pass by to our west and eventual south, it will bring widespread precipitation to the area. Sub- freezing temperatures area wide will result in wintry precipitation across the region. The main uncertainty with this system remains where the mixing sets up and how far east the warm nose aloft gets. Another uncertainty point is where the strongest mesoscale banding sets up. The latest trend in guidance shows a slight push to the north with a potentially more widespread sleet event with a lower risk of freezing rain. There remains high uncertainty how much and where the sleet/snow mix will end up panning out for the region, but the main takeaway here is that we continue to expect a wintry mess for much of the region Friday afternoon through Saturday morning. Current consensus keeps the weather mainly snow along a line from around Mount Pocono PA down south and east towards Middlesex and Monmouth counties in NJ and all points north and east. A general 5-8 inches of snowfall (with some sleet mixing possible) remains possible for most of central and northern NJ from I-195 north as well as the Pocono Plateau, and locations north and west of the Lehigh Tunnel/Blue Mountain range. However, some localized areas in this zone may see amounts higher than forecasted depending on where the mesoscale banding sets up. The banding will produce snowfall rates over an inch per hour. Lift should be be quite strong in the northern half of our area which lies within the left exit region of the polar jet, coinciding with strong 700 mb frontogenesis nearby. In general, thermal profiles continue to show freezing temperatures through the atmosphere across this corridor, though the warmer trend is showing some locations being impacted by a warm nose aloft (around the 700-850mb layer), potentially leading to more sleet mixing in should this warming trend continue. Probability of hitting warning level snow in these areas ( > 6 inches) has now actually decreased slightly, down to 50-70%. Confidence dwindles in the forecast the further south you go towards Philadelphia. For areas in PA south of I-78, a warm nose aloft will move in somewhere between 700 and 850 mb. A thicker warm nose would result more in freezing rain as the surface stays below freezing with a modestly strong cold air damming setup while a thinner warm nose and higher up towards 700-750 mb would result in more sleet. Latest model trends are favoring thinner warm nose with sleet. Regardless, this warm nose likely will cut into totals, but given a lower warning criteria in most of those counties south of I-78, there still is around 30-50% of warning-level snow based on the NBM, though WPC Probabilistic Guidance has it lower than that. Nonetheless, a Winter Storm Watch remains in effect for all PA counties except Delaware and Chester County, where mixed precipitation totals will cut snow even further. Within this portion of the Watch, 3-5" of snow is expected, with sleet mixed in. Some of this Watch may be converted to an Advisory depending how things trend in subsequent forecast cycles. East of Philadelphia, but south of I-195, more of a marine influence will possibly cut into snow totals with some mixing, with a rain/snow/sleet mix. However, similar to adjacent areas in PA, probabilistic guidance has decreased in warning-level snow and sleet, with 30-50% probabilities of reaching criteria. Given the level of uncertainty, the Winter Storm Watch for Ocean, Burlington, and Camden County in this part of NJ will remain up. Important to note that the freezing rain potential in these areas is much lower compared to SE PA, but the possibility of a rain/snow/sleet mix cutting into totals is on the table. Looking at 4-6" currently within the Watch in this part of NJ. For areas outside the watch in far SE PA, Delmarva, and far South Jersey, snow is expected at onset, but a quick changeover to sleet, freezing rain, or all rain is anticipated. This will limit snow amounts to around a coating over southern Delmarva, and around 3 inches or less in far southern NJ, northern DE, and southeastern PA. The cutoff in snow amounts likely will be tighter than what the current forecast has, but did not have the confidence to nail down exactly where that would be. Would not be a surprise to see Advisories posted for parts of South Jersey, northern DE, and SE PA as snow could get to Advisory level. There also likely (60-80% chance) will be measurable ice over northern DE and SE PA. Long story short, despite the high uncertainty with the final snow and sleet totals, disruptions are to be expected Friday afternoon and Friday Night as this system moves through. Periods of snow, sleet, and/or freezing rain/ice will make travel dangerous and anyone with travel plans will see disruptions. Stay tuned to the updated forecast as changes are likely. The heaviest snow tapers off Saturday morning, but some lingering snow showers are still possible, mainly for the northern half of the area. Temperatures on Saturday will be in the upper 20s/low 30s for the northern half of the area, with mid to upper 30s and low 40s for the rest. There will not be any wind concerns with this event as the pressure gradient is weak. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... This period starts out on the dry side in between systems. Saturday night lows look to be normal or slightly below under mostly cloudy skies. Clouds are expected to remain on Sunday and rain chances will increase as we move through the day. A wintry mix is possible across the southern Poconos and NW New Jersey. Highs on Sunday will be about normal for this time of year, maybe slightly below. For Sunday night into Monday, the main impact of a frontal system appear to be the stronger winds as precipitations for the moment appear to be an all rain event with temps warming through the evening. Can't rule out some mixing across the far NW of the forecast region however. Temperatures will likely settle around normal. Timing of the cold front will largely dictate temps Monday with a colder solution more likely if the front clears earlier. A modestly strong pgf should lead to blustery winds potentially gusting to 25-35mph Monday afternoon and Tuesday. With high pressure building a cold airmass behind the front expect highs to be well below normal in the upper 20s to low 30s Tuesday. && .AVIATION /07Z THURSDAY THROUGH MONDAY/... The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas. Rest of Tonight/Christmas Eve...VFR. Winds light/variable, then settling out of the south around 5 kts or less late. High confidence. Thursday/Christmas Day...Some brief MVFR conditions possible in low clouds, mainly from KPHL southwards. SW winds 10-15 kts shifting NW becoming gusty in the afternoon. Low confidence on cig reductions medium confidence wind forecast. Outlook... Friday through Saturday morning...An impactful winter storm will move through the region starting late on Friday. KTTN likely will be all snow, with KRDG/KABE/KPNE/KPHL/KILG all seeing multiple precipitation types over this period. Precipitation will mainly be snow, but a changeover to sleet and/or freezing rain is expected at some point. KMIV/KACY should start out as snow with relatively quick change to a mix or all rain. IFR conditions likely through this time frame, but periods of LIFR cannot be ruled out. Saturday Afternoon...Sub-VFR conditions expected with low clouds and scattered snow showers. Saturday night...VFR conditions expected. Sunday...Sub-VFR conditions likely in low clouds and rain, especially later in the day. Sunday night...Sub-VFR conditions likely in low clouds and rain. Monday...A return to VFR is likely. && .MARINE... Winds and seas diminish below SCA levels all zones tonight. Small Craft Advisory conditions are expected to develop this morning another cold front passes. Outlook... Friday through Friday Night...SCA conditions dissipate with rain and snow anticipated over the waters on Friday Night, likely reducing visibility. Saturday...SCA conditions possible (40-60%) as seas near 5 feet. Saturday night...SCA conditions possible. Winds should relax, but seas are expected to remain near/around 5 feet. Sunday...SCA conditions possible in the morning as 5 foot seas hang on. Sub-SCA expected in the afternoon. Sunday night and Monday...SCA conditions expected once again. Gale force gusts possible. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...Winter Storm Watch from Friday afternoon through Saturday morning for PAZ054-055-060>062-071-103>106. NJ...Winter Storm Watch from Friday afternoon through Saturday morning for NJZ001-007>010-012>015-018>020-026-027. DE...None. MD...None. MARINE...Small Craft Advisory from 7 PM this evening to 5 AM EST Friday for ANZ430-431. Small Craft Advisory from 10 AM this morning to 1 PM EST Friday for ANZ450>455. && $$ SYNOPSIS...RCM/Staarmann NEAR TERM...Deal/MJL/RCM SHORT TERM...MJL LONG TERM...Deal/Kruzdlo AVIATION...Deal/Hoeflich/Kruzdlo/MJL/RCM MARINE...Deal/Hoeflich/Kruzdlo/MJL