335 FXUS61 KPHI 112002 AFDPHIArea Forecast Discussion National Weather Service Mount Holly NJ 402 PM EDT Sat Oct 11 2025
.SYNOPSIS... A coastal storm will affect the region tonight through early next week bringing significant impacts to parts of our area. Improving conditions expected by Tuesday as the storm weakens and moves out to sea. High pressure will begin building back into the region during the middle to end of next week.
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.NEAR TERM /THROUGH MONDAY/... ***Significant impacts possible from a strong coastal storm Sunday through Monday***
As of 11 AM this morning, the coastal low about 180 miles off the South Carolina coast was a closed low with a central pressure less than 1004 mb. This is going to be the start of the coastal low impacts for our region through Monday. This low and potentially a second surface low (more on that in the next paragraph) will bring tidal/coastal flood, wind, and rain impacts to our region through the near term period.
What has changed: Most notably, a majority of the main deterministic models are now depicting a double barreled low solution. These solutions show a second surface low developing closer to Long Island as the northern upper level trough approaches. The net result of this for our area could be lower total rain amounts, and wind impacts more confined to the coast. As we get closer, have increase confidence to change the high wind watch to a high wind warning (for Cape May and the rest of the coastal strip) and wind advisory (for inland portions of Sussex Co Delaware, Inland Atlantic Co, SE Burlington Co, Inland Ocean Co, and Inland Monmouth Co in NJ.
Hazards: For more information on the tidal/coastal flood hazards and marine navigation hazards, please see the Tides/coastal flooding and marine sections below.
Wind...As mentioned above, it is looking more likely with the latest guidance that the stronger winds will be confined closer to the coast. Consequently changed the watch to a combination of high wind warning (for the coastal strip, plus all of Cape May County), and wind advisory for the remainder of what was in the watch area. The main period of impact looks to be from 15Z/11AM EDT tomorrow through Sunday night.
Rain...Didn`t make any significant changes with the rain amounts with this forecast. The current forecast is pretty much in the middle of guidance, but given the uncertainty with the double barreled low solutions, there is a wide range of rain amount guidance for an event that will essentially happen within the next 48 hours. Current forecast is for 0.75 to 2 inches for inland locations and 1 to 3 inches for coastal areas. All that being said, with how long of a duration the rain is falling, the freshwater/rainfall flooding threat is limited. However, minor flooding in poor drainage areas is possible, and there remains a concern that the rain will exacerbate tidal/coastal flooding impacts.
Timing: We`ve seen the first few showers with this system already today. However, the main rain shield won`t start to move into our region until late tonight, with the bulk of the rain falling from early Sunday morning through the day on Tuesday. As for winds, the main period of concern is from late Sunday morning through Sunday night.
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.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/... Conditions look to begin to improve Monday night as the initial low looks to weaken but with the potential double barrel solution and a secondary low developing, periods of light rain and gusty winds will continue through much of the overnight hours.
Through Tuesday, the remaining low will begin to shift further away, leaving just breezy conditions (highest gusts around 20-30 mph along the coast) as well as a few lingering showers near the coast. The low will push out to sea by Tuesday night with dry conditions across the region and a gradual clearing of skies.
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.LONG TERM /WEDNESDAY THROUGH SATURDAY/... Broad high pressure will build across the Great Lakes region from the middle of next week through the end of the long term period and extend out over our region. As a result, the forecast for next Wednesday through Saturday is currently dry across the whole region. Wednesday could remain relatively mild before CAA ramps up with northwest flow as the high approaches. The cooler airmass will arrive by the end of the week, with below normal temperatures anticipated for Thursday and Friday. Temperatures may begin to moderate on Saturday as the mid-level northwest flow weakens.
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.AVIATION /19Z SATURDAY THROUGH THURSDAY/... The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas.
Rest of Today...Mainly MVFR conditions continue with showers and lower ceilings continuing to overspread the area. Brief improvements to VFR remain possible this afternoon between showers. Winds east to northeast 10 kts, stronger at KACY. Moderate confidence.
Tonight...Predominately MVFR conditions expected with more rain overspreading the area, especially by late tonight. Northeast winds will also increase closer to 15 knots with gusts up to 20-25 kts, higher at KACY. Moderate confidence.
Sunday through Monday...MVFR to IFR conditions expected with moderate to heavy rain moving through and gusty winds. Northeast wind gusts near 45 kt possible at KACY. Gusts out of the northeast around 25-35 kt expected at the I-95 terminals and KMIV, with 20-30 kt anticipated within the Lehigh Valley. Moderate confidence.
Outlook...
Monday Night...Restrictions expected with showers and low clouds. Wind gusts diminish to around 15-25 kt out of the north/northeast.
Tuesday...Conditons improve but sub-VFR conditions possible with lingering showers and clouds. Wind gusts could get near 20 kt at times.
Wednesday and Thursday..VFR with no significant weather.
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.MARINE... No changes made at this point to the marine hazards. Easterly winds and waves will continue to increase. Late Saturday night, expect winds to shift out of the northeast and increase further. The strongest winds are expected during the day on Sunday continuing through Sunday Evening before gradually subsiding. Still expecting storm force winds on the lower Delaware Bay and the Atlantic coastal waters. For the upper Delaware Bay, expect gale conditions.
Dangerous seas upward of 15 to 20 feet expected. Periods of moderate to heavy rain and sea spray restricting visibility at times.
Outlook...
Monday night through Thursday...Conditions will begin to improve as the storm weakens and begins to move away. However, gale force winds may linger through Tuesday and elevated seas above 5 feet may linger through Thursday.
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.TIDES/COASTAL FLOODING... We`ll continue with the Coastal Flood Advisories for the next tide cycle before the larger event for Sunday. The latest numbers for the upcoming tide were similar to previous fcst, so saw no need for any major changes. Either low-end minor tidal flooding or just below that is expected this evening and into the overnight.
Meanwhile, there is an increasing risk of moderate to major coastal flooding impacts beginning Sunday through Monday as a strong coastal storm impacts the region. Guidance still varies in potential outcomes of this storm with regard to severity of coastal flood impacts locally, however we remain very concerned about the potential for significant impacts from this storm along our coasts. At this time, the greatest threat of impacts are anticipated to occur along the Atlantic coasts of New Jersey and Delaware, and Delaware Bay. Confidence has increased enough such that we`ve upgraded the Coastal Flood Watch to a Warning Sunday through Monday.
Severe beach erosion and dune breaching are possible along the entire New Jersey Shore and for Delaware beaches due to the very high surf conditions that are expected. Interests along the Atlantic coast, Delaware Bay, back bays, and tidal waterways should remain alert for forecast updates regarding this potentially significant coastal flood event.
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.PHI WATCHES/WARNINGS/ADVISORIES... PA...Coastal Flood Advisory from 2 PM Sunday to 11 PM EDT Monday for PAZ070-071-106. NJ...Coastal Flood Warning from 11 AM Sunday to 9 PM EDT Monday for NJZ016. Coastal Flood Advisory until 8 AM EDT Sunday for NJZ021>025. Coastal Flood Warning from 8 AM Sunday to 8 PM EDT Monday for NJZ012>014-020>027. Wind Advisory from 11 AM Sunday to 6 AM EDT Monday for NJZ013- 020-022-027. High Wind Warning from 11 AM Sunday to 6 AM EDT Monday for NJZ014-023>026. Coastal Flood Advisory from 2 PM Sunday to 11 PM EDT Monday for NJZ017>019. DE...Coastal Flood Warning from 11 AM Sunday to 9 PM EDT Monday for DEZ001. Coastal Flood Advisory until 8 AM EDT Sunday for DEZ002>004. Coastal Flood Warning from 8 AM Sunday to 8 PM EDT Monday for DEZ002>004. Wind Advisory from 11 AM Sunday to 6 AM EDT Monday for DEZ003. High Wind Warning from 11 AM Sunday to 6 AM EDT Monday for DEZ004. MD...None. MARINE...Gale Warning until 8 PM EDT Monday for ANZ430. Storm Warning until 8 PM EDT Monday for ANZ431-450>455. Small Craft Advisory until 6 PM EDT this evening for ANZ450>455.
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SYNOPSIS...AKL NEAR TERM...Johnson SHORT TERM...AKL LONG TERM...AKL AVIATION...AKL MARINE...AKL/Johnson TIDES/COASTAL FLOODING...OHara
NWS PHI Office Area Forecast Discussion