


Area Forecast Discussion
Issued by NWS Mt. Holly, NJ
Issued by NWS Mt. Holly, NJ
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511 FXUS61 KPHI 081834 AFDPHI Area Forecast Discussion National Weather Service Mount Holly NJ 234 PM EDT Tue Jul 8 2025 .SYNOPSIS... Bermuda high pressure will be in place through the weekend, eventually breaking down for the start of the new work week. Several disturbances will pass through the region during this time as well. && .NEAR TERM /THROUGH WEDNESDAY/... A Severe Thunderstorm Watch has been issued for the entire area until 9 PM this evening. Prev Disc: The overall unsettled, active, and tropical weather pattern will continue Tuesday due to a slow-moving cold front which will work its way toward the area but won`t actually cross through the area until mid-late week. This boundary will act as the trigger for convection in both the severe and hydro departments on Tuesday. PWATs will remain in the range of 1.8-2.3 inches; tall, skinny CAPE on the order of 1500-2500 J/kg; and relatively low unidirectional effective shear up to 20 kt supports the potential for training convection where any residual boundaries are in place. There won`t be much dry air to speak of in the DCAPE department, however steep low-level lapse rates combined with water loaded downdrafts will yield a damaging wind threat with any stronger or more organized updrafts. As a result, the Storm Prediction Center and Weather Prediction Center continue to highlight the threats for both severe weather and flash flooding with most of our area highlighted in SLIGHT risks for both. As a result, a new Flood Watch for flash flooding has been issued that includes all of our forecast area except for Carbon and Monroe Counties. This is in effect from 2 PM Tuesday to midnight. In terms of the timing of convection, it should stay dry through the morning with convection firing near the cold front over our NW zones by the early to mid afternoon period. It should then push south/east through the urban corridor around the late afternoon into the early evening before moving offshore by late evening. As for temperatures, Tuesday will feature mostly sunny skies in the morning with increasing clouds ahead of the thunderstorms in the afternoon. Forecast highs are expected to be in the upper 80s to mid 90s across most of the area with tropical dew points remaining in the low to mid 70s. As a result, heat indicies are expected to range between 100-105 degrees across much of the area. For this reason, kept current heat headlines in place except added Morris County in New Jersey. The Advisory runs from 10 AM to 8 PM Tuesday. Convection should be mostly winding down by the overnight period Tuesday night as the cold front pushes southward before tending to stall over southern NJ into Delmarva. The front will also be quite weak and diffuse as far as there really being a temperature and dew point gradient across it. As a result, it will be another mild and muggy night. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... A warm and humid airmass will be over the Northeast and Mid- Atlantic for the Short Term period. Surface dew points will be in the low to mid 70s, along with highs generally in the mid 80s. This will yield heat index values in the low to mid 90s. These high dew points will also keep low temperatures at night quite warm, and lows will generally be in the lower 70s. Unsettled weather will remain on tap as a frontal boundary will hover over the area. Abundant low level moisture will be in place given those high dew points, and PWATs will be up to and in excess of 2 inches. Lingering showers and thunderstorms Wednesday evening will be capable of locally heavy rain and flash flooding. With SB CAPE values up to 1500 J/kg and 30 to 35 kt of 0-6 km Bulk Shear, cannot rule out damaging winds from thunderstorms. Another round of showers and thunderstorms will impact the area Thursday afternoon and evening as shortwave energy approaches from the west and passes through the region. Given how warm and humid conditions will be, locally heavy rain and damaging wind gusts are possible once again. This pattern continues on Friday. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... Fairly typical summertime pattern on tap for the Long Term period with warm and humid conditions. Surface dew points will generally be in the mid 70s or so from Friday night through around Sunday, and then dew points look to come down a bit for the start of the new work week, generally in the upper 60s to low 70s. It is also possible that during the peak heating of the day that dew points drop by a few degrees due to mixing. Highs will generally be in the mid to upper 80s, possibly around 90 in some spots. This will give way to max heat index values in the low to mid 90s. A series of disturbances will pass through the region from time to time, but confidence in timing and placement is low. Will generally follow the NBM and go with 30 to 50 percent PoPs for most of this time, though the NBM is indicating 60 percent PoPs for the southern Poconos, Lehigh Valley, and Berks county on Sunday due to a stronger system possibly approaching then. Important to note that any showers and thunderstorms will mostly be in the afternoon and evening hours, and there are not many factors indicating precipitation would be widespread and organized at this time. && .AVIATION /19Z TUESDAY THROUGH SUNDAY/... The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas. Rest of Today...Primarily VFR expected for the rest of the afternoon. Scattered thunderstorms likely move into the area after 20Z, so have TEMPO group at all terminals. VSBY/CIGs restrictions possible in thunderstorms with locally gusty winds. Southwest winds around 5-10 kt with localized gusts up to 15 kt. Moderate confidence. Tonight...VFR expected with MVFR ceilings possible after 06Z as some stratus develops, however confidence is not high. Showers and thunderstorms will wane into the evening hours and taper off by midnight. Southwest winds around 3-5 kt. Moderate-low confidence. Wednesday...Primarily VFR with another round of showers and thunderstorms developing by mid-late afternoon. Any showers and storms may cause localized areas of VSBY/CIG restrictions. Southwest winds around 5-10 kt. Moderate confidence. Outlook... Wednesday night through Sunday...Overall, VFR conditions. However, afternoon and evening SHRA/TSRA may result in brief sub-VFR conditions if a given storm passes over a terminal. Sub- VFR conditions possible at night due to fog and low clouds, but confidence low on timing and placement. && .MARINE... Marine hazards are no longer in effect through tonight. However showers/storms moving over the waters tonight could bring locally strong wind gusts over 34 knots along with locally higher seas. Outlook... Wednesday night through Sunday...Sub-SCA conditions for this period. Afternoon and evening showers and thunderstorms possible each day. VSBY restrictions possible from time to time, especially at night. Rip Currents... For today, winds shift southwesterly becoming more alongshore flow around 5-10 mph in the morning increasing to 10-15mph in the afternoon. Breaking wave heights should be in the 2-4 foot range depending on beach orientation with a primary SE swell increasing to 4 feet at a 6-8 second period. Given the tides will be around low tide in the morning with the increase in swell, will maintain a HIGH risk for rip currents for the easterly facing beaches and MODERATE elsewhere. Similar conditions are expected for Wednesday except we will confine the HIGH risk of rip currents to the beaches in Atlantic and Cape May Counties in NJ with a MODERATE risk elsewhere. Rip currents occur often in the vicinities of jetties and piers and the speed of the currents are generally maximized at low tides. For specific beach forecasts, visit weather.gov/beach/phi && .HYDROLOGY... A new Flood Watch for flash flooding has been issued for today and is in effect until midnight. This is a result of widespread showers/storms expected to develop capable of producing rainfall rates of 2 inches per hour. If storms train over any one area for a period of time, this could result in localized rainfall totals of 3 to 4 inches. Main stem river flooding is not anticipated but flash flooding of smaller streams/creeks and areas of poor drainage will be possible. Please heed any road closures and law enforcement instructions in case of flooding. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...Heat Advisory until 8 PM EDT this evening for PAZ070-071- 101>106. Flood Watch until midnight EDT tonight for PAZ060>062-070-071- 101>106. NJ...Heat Advisory until 8 PM EDT this evening for NJZ008>010- 012>023-027. Flood Watch until midnight EDT tonight for NJZ001-007>010- 012>027. High Risk for Rip Currents until 8 PM EDT this evening for NJZ024>026. DE...Heat Advisory until 8 PM EDT this evening for DEZ001>003. Flood Watch until midnight EDT tonight for DEZ001>004. MD...Heat Advisory until 8 PM EDT this evening for MDZ012-015-019- 020. Flood Watch until midnight EDT tonight for MDZ012-015-019-020. MARINE...None. && $$ SYNOPSIS...MPS NEAR TERM...DeSilva SHORT TERM...MPS LONG TERM...MPS AVIATION...DeSilva/MPS MARINE...DeSilva/MPS HYDROLOGY...