Area Forecast Discussion
Issued by NWS Upton, NY

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718 FXUS61 KOKX 081450 AFDOKX Area Forecast Discussion National Weather Service New York NY 1050 AM EDT Tue Jul 8 2025 .SYNOPSIS... A slow moving cold front settles over the area this afternoon and evening. The front likely stalls nearby the rest of the week leading to unsettled conditions. The front may push further south of the area for the upcoming weekend. && .NEAR TERM /THROUGH TONIGHT/... Key Messages: *Hot and humid today with temperatures in the upper 80s to middle 90s with heat indices in the upper 90s to around 100. The heat advisory has been expanded to include all of the area except southeast Suffolk County this afternoon/early evening. *Showers and thunderstorms this afternoon and evening may produce torrential downpours leading to a risk of flash flooding. A flood watch is in effect for the entire area 2pm this afternoon through 2am Wednesday. *A few thunderstorms may also be severe with damaging wind gusts with the potential a bit higher across NE NJ, NYC metro, and portions of the Lower Hudson Valley. A slow moving cold front will enter the area today and may stall nearby tonight. The front will interact with a tropical air mass with PWATs around 2-2.25 inches. Models also indicate a modest 80-90 kt jet streak over New England with the region setting up in the favored right entrance region. This will add some synoptic support for convective development this afternoon and evening. Warm rainfall processes due to high freezing levels and a long/skinny CAPE profile support a torrential rainfall threat. The combination of these ingredients brings the potential of mainly localized flash flooding. WPC has maintained a slight risk for excessive rainfall across the entire area. The last few runs of the HREF indicate a 3-hr QPF PMM 10 percent probability of greater than 3 inches in 3 hours late this afternoon and evening. It should be noted that we have typically seen this probability of 30 percent or more coinciding with some of the more significant flash flood events in recent years. While the current 3-hr QPF PMM for greater than 3 inches is around 10 percent, it does indicate potential of excessive rainfall. The CAMs vary with the location of the convection, so confidence is not high where the flood potential may be greatest. However, where the CAMs do simulate convection, 1-hr rainfall rates could be 1-2" if not even slightly higher in the heaviest activity. The high end of these rates may end up localized, but the threat does exist area wide. For these reasons described above, have issued a flood watch for the entire area from 2pm this afternoon through 2 am Wednesday. Total rainfall out of this event will vary widely, but the heaviest activity could produce 2-3 inches with locally higher amounts. Some convection may persist overnight, but coverage should start to diminish. If trends on the guidance later today indicate convection may persist longer, parts of the watch may need be extended. There is also a severe thunderstorm threat this afternoon and evening. CAPE values of 1500-2000 J/kg should develop with strong heating. Shear is not impressive as the mid level flow is relatively weak, but an average of about 25 kt should allow for clusters or small line segments to develop. The deep moisture content of the air could allow for some damaging wind gusts in the most organized activity. SPC has expanded the slight risk into NE NJ, NYC metro, and portions of the Lower Hudson Valley and has maintained a marginal risk elsewhere. The other concern for today will be hot temperatures and high humidity values. A review of observational data from Monday indicates many spots in the Lower Hudson Valley and southern CT observed a few hours of heat indices at or just above 95. The forecast heat indices late this morning and early afternoon reach the mid to upper 90s. This supports the two day heat advisory criteria. For Western Suffolk and the north fork of Suffolk County, heat indices peak around 100 degrees this afternoon, supporting the 1 day criteria. For these reasons, the heat advisory has been expanded to include all but SE Suffolk where heat indices peak in the low 90s. Southeast CT is also borderline, but due to collaboration with WFO BOX, have included Middlesex and New London. Otherwise, it will remain muggy tonight. Lows look fall into the upper 60s inland and low/mid 70s near the coast. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... Unsettled conditions will persist Wednesday and Thursday. Temperatures should be held down a bit with the front stalled nearby. More organized support for convection may lie to our southwest on Wednesday. Heights then fall as a shortwave trough approaches Wednesday night. This could bring an expansion of showers and possible storms, lingering into Thursday. Guidance continues to differ on the evolution and timing of the greatest coverage however, so confidence is low on any impacts at this time. The main concern will continue to be locally heavy downpours. WPC has maintained a marginal risk for excessive rainfall both days. High temperatures on Wednesday look to reach the middle and upper 80s. A few isolated spots could touch 95 heat index, but currently not anticipating this to be widespread due to increased cloud cover. Temperatures trend lower on Thursday with highs mainly in the low to mid 80s and heat indices peaking around 90 in the warmest spots. && .LONG TERM /FRIDAY THROUGH MONDAY/... The NBM was followed with no changes. Key Points: * A stalled front will remain in the vicinity of the forecast area Friday into early next week. * Expect a chance of showers and/or thunderstorms each afternoon each day, especially west of NYC. * Temperatures should be right around average for this time of the year with highs each day in the 80s. && .AVIATION /15Z TUESDAY THROUGH SATURDAY/...
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A cold front approaches the terminals today and remains in the vicinity through the TAF period. VFR today outside of shwrs and tstms. Isold-sct shwrs and tstms possible roughly 16-00Z, then potential for more nmrs tstm clusters overnight. No changes to the TAF tstm fcst attm, although changes possible with the 18Z issuance, particularly for tngt. MVFR cigs will be possible tonight, improving to VFR on Wed. SW to WSW winds around 10 kt today. Some of the interior terminals may see winds more W through the day. Given the nearby front there is more uncertainty than usual with wind direction starting this afternoon. Winds become light tonight. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... Some variability in wind direction expected this aftn and eve due to position of the front. Still some uncertainty with exact timing and coverage of showers/thunderstorms. .OUTLOOK FOR 12Z WEDNESDAY THROUGH SATURDAY... Wednesday through Friday: Afternoon and evening showers/tstms possible each day, with brief MVFR or IFR conditions. Saturday: Mainly VFR. A slight chance for showers and an isolated thunderstorm with MVFR or lower conditions. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90
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&& .MARINE... Seas build toward 5 ft early this morning on the ocean from Fire Island Inlet on east with a building SE swell. These conditions will persist through early Wednesday morning. The SCA remains in effect for these waters. Otherwise, winds and seas should largely remain below SCA levels the rest of the week and potentially into next weekend. && .HYDROLOGY... A flood watch has been issued for the entire area 2pm this afternoon through 2am Wednesday. Showers and thunderstorms this afternoon and evening have the potential to produce torrential downpours with rainfall rates 1-2" an hour. It is quite possible for a spots to exceed 2" an hour at times in the heaviest activity. WPC has maintained a slight risk for excessive rain across the entire area highlighting the mainly localized flash flooding risk. A few of the quicker responding rivers, streams, and creeks nay experience flash flooding. A marginal risk of excessive rainfall remains in place for much of the area on Wednesday and Thursday with a continued localized flash flooding threat. && .TIDES/COASTAL FLOODING... There is a high rip current risk at all ocean beaches into this evening due to building surf to 4-5 ft and building SE swell. The risk remains high on Wednesday due to the linger SE swell. && .OKX WATCHES/WARNINGS/ADVISORIES...
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CT...Heat Advisory until 8 PM EDT this evening for CTZ005>012. Air Quality Alert until 11 PM EDT this evening for CTZ005>012. Flood Watch from 2 PM EDT this afternoon through late tonight for CTZ005>012. NY...Heat Advisory until 8 PM EDT this evening for NYZ067>075- 078>080-176>179. Air Quality Alert until 11 PM EDT this evening for NYZ078>081- 177-179. Flood Watch from 2 PM EDT this afternoon through late tonight for NYZ067>075-078>081-176>179. High Risk for Rip Currents until 8 PM EDT this evening for NYZ075- 080-081-178-179. NJ...Heat Advisory until 8 PM EDT this evening for NJZ002-004-006- 103>108. Flood Watch from 2 PM EDT this afternoon through late tonight for NJZ002-004-006-103>108. MARINE...Small Craft Advisory until 2 AM EDT Wednesday for ANZ350-353.
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&& $$ SYNOPSIS...DS NEAR TERM...DS SHORT TERM...DS LONG TERM... AVIATION...BC/JMC MARINE...DS HYDROLOGY...DS TIDES/COASTAL FLOODING...