Area Forecast Discussion
Issued by NWS Upton, NY

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344 FXUS61 KOKX 101809 AFDOKX Area Forecast Discussion National Weather Service New York NY 209 PM EDT Thu Jul 10 2025 .SYNOPSIS...
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A stagnant pattern will keep chances for some showers and thunderstorms in the forecast thru Fri. High pressure builds off the New England coast this weekend, before a frontal system approaches from the west early next week. The associated cold front moves through on Monday, and high pressure returns into midweek.
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&& .NEAR TERM /THROUGH TONIGHT/...
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As an upr trof continues to track ewd this aftn and eve, the associated dpva will do so as well. This will tend to keep the best upr support over the Atlc. The airmass over most of the CWA has been worked over as well, so without the good forcing, it may be difficult to initiate any substantial convection this aftn and eve across most of the area. Extreme nwrn zones look to destabilize most based on clearing indicated on stlt and the lack of pcpn earlier today. As a result, the best chances for isold-sct aftn/eve development should be in those areas. With the loss of daytime heating and the passage of the upr trof axis overnight, any pcpn should wind down across the CWA. With a lgt to calm flow tngt, some patchy fog is possible with the llvl moisture lingering.
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&& .SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
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Increasing CAPE and decreasing CIN on Fri, but subsidence across the region is expected to limit/inhibit convective initiation attm. Still cannot rule out a few isold or widely sct aftn/eve tstms, particularly across the interior where there is some terrain to work with. The GFS does bring isold activity across the entire CWA, but without support from the NAM, have left the NBM pops unaltered. Some patchy fog again modeled for Fri ngt. A very subtle lljet may try to produce a few shwrs or tstms overnight, again mainly nwrn areas, but the NBM has not latched on to this yet so something to look for. The NAM and GFS have a weak signal. Hotter on Fri with all areas in the 80s, and the usual hot spots across the SW approaching 90. The MAV and NBS has 90 at EWR.
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&& .LONG TERM /SATURDAY THROUGH THURSDAY/...
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High pressure builds off the coast of Nova Scotia and maintains an offshore flow much of the weekend. This should help keep much of southern CT and LI dry, though inland western areas will see showers and thunderstorms possible each afternoon with a moist BL in SE flow and diurnal heating helping to build instability. Thereafter, a broad mid level trough centered over the Upper Great Lakes translates east into early next week, helping advance a frontal system toward and through the region, bringing increased chances for a more widespread rainfall, especially on Monday ahead of the cold front. Parameters appear at least marginally supportive of thunderstorm development, but steering flow appears progressive enough to mitigate significant flood concerns. Conditions dry behind the fropa into midweek as weak high pressure drifts in and NW flow aloft looks to lower the humidity. Temperatures through the period look to largely stay in the 80s most afternoons thru early week, with a gradual warm up then into mid next week. National blended guidance was followed for this update.
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&& .AVIATION /18Z THURSDAY THROUGH TUESDAY/...
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A surface trough remains in the vicinity of the terminals through Friday. Mainly VFR with MVFR across Long Island east of the NYC terminals, and IFR at KGON. An isolated thunderstorms is possible at KSWF late afternoon. Conditions lower late this evening and tonight, becoming MVFR at the NYC metro terminals, and IFR, possibly LIFR a the other terminals, except KSWF which may only briefly be MVFR toward Friday morning. Timing and lowering of flight categories are somewhat uncertain. Conditions slowly improve to VFR Friday morning, except at KGON which may remain MVFR into the afternoon. An isolated thunderstorm will again be possible at KSWF Friday afternoon. Winds will be light S to SE this afternoon, and become light and variable at all terminals this evening into tonight. A light SE flow develops Friday morning, except a light NE flow initially at KLGA. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... Amendments likely late tonight into Friday morning for timing and flight categories of ceilings/visibilities. .OUTLOOK FOR 18Z FRIDAY THROUGH TUESDAY... Friday afternoon - Sunday: Mainly VFR. A chance of showers and thunderstorms during the afternoon and early evening near and northwest of the NYC terminals. Monday: VFR. A chance of showers and thunderstorms, becoming likely during the afternoon northwest of the NYC terminals. MVFR conditions in showers and thunderstorms. Tuesday: VFR. Slight chance of showers and thunderstorms. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90
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&& .MARINE...
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Outside of tstms, winds and seas are expected to remain blw sca lvls thru Fri ngt. Light flow and low seas should then maintain sub Small Craft Advisory conditions on all coastal waters through early next week.
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&& .HYDROLOGY...
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Any tstms that develop thru Fri ngt could produce highly localized minor flooding. No significant hydro concerns in the long term.
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&& .TIDES/COASTAL FLOODING... Rip current risk forecast is moderate both for today and Friday for the ocean beaches of NYC and Long Island due to onshore flow of near 5-10 kts as well as 3 to 4 ft of 7-8 sec period swell as well as some smaller onshore long period swell of 1 ft and 11-12 sec period. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...JMC/DR NEAR TERM...JMC SHORT TERM...JMC LONG TERM...DR AVIATION...MET MARINE...JMC/DR HYDROLOGY...JMC/DR TIDES/COASTAL FLOODING...