Area Forecast Discussion
Issued by NWS Upton, NY
Issued by NWS Upton, NY
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493 FXUS61 KOKX 011735 AFDOKX Area Forecast Discussion National Weather Service New York NY 135 PM EDT Thu Oct 1 2026 .WHAT HAS CHANGED... Rain chances gradually coming up for Sunday. && .KEY MESSAGES... 1) Conditions gradually warm and remain mostly dry ahead of an approaching cold front through Friday. 2) Increasing chances of rain for Sunday as a frontal wave possibly grazes the area. No impacts expected. && .DISCUSSION... .KEY MESSAGE 1... The combination of a ridge over the southeast and an amplifying shortwave trough racing across southern Canada will allow for a warmup through Friday. A deep-layered westerly flow between the two features will send 85h temps of around 15C into the area by this evening. Temperatures though will be limited today by an abundance of mid and high level cloudiness associated with convection over the mid section of the country. Highs are forecast into the 70s today, with much of the area getting into the lower 80s Friday, which is about 10 degrees above normal. Clouds are forecast to diminish some as the day progresses, clearing out this evening. A cold front associated with the aforementioned upper trough approaches on Friday, passing through the area during the late afternoon into early evening hours. Latest CAMs not showing much with the cold frontal passage. No surprise here with not much instability and poor mid-level lapse rates. However, the non-CAM models are showing some QPF across area, generally a tenth or two. NAM12 is very bullish with amounts over an inch across the Lower Hudson Valley and interior SW CT. The latter is an outlier. NBM PoPs generally in the chance (30-50%) category, but slightly higher across eastern LI. There is not a whole lot of upper support with the main lift coming with the front itself. Thus, for the time only expecting some scattered showers with the frontal passage. A large dome of high pressure will then build east from the Great Lakes on Saturday with more seasonable temperatures. .KEY MESSAGE 2... Much of the guidance continues to trend toward increasing chances for rain on Sunday. This yo-yoing the last several days is related to the amount backing ahead of an approaching shortwave and how close a surface frontal wave gets to the area. It`s still a close call with the forecast area on the NW fringe of the system. Rainfall amounts look light at this time with the area getting scraped. 01Z NBM prob > 0.25" about 20 to 40 percent across the area (highest at the coast), but even lower for the LREF (GEFs, GEPs, EPS) mean. && .AVIATION /18Z THURSDAY THROUGH TUESDAY/... High pressure remains centered offshore through Friday. A cold front approaches late Friday into Friday night. Mainly VFR thru the TAF period. Can not rule out isolated sub- IFR cigs late tonight into early Friday morning, mainly at KGON. Also, can not rule out some MVFR cigs in showers late Friday afternoon/evening in any SHRA. A general SW flow prevails through the day, possibly backing S at KJFK. Speeds will be around 10 kt this afternoon and will lighten during the evening. Winds may become light and variable tonight. Winds become SW once again on Friday with speeds around 10kt. Gusts will also be possible, mainly between 18-20kt. For the 30 hours TAF sites, winds will become more W late, with KSWF becoming NW with the passage of a cold front late Friday. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... No unscheduled amendments expected. .OUTLOOK FOR 18Z FRIDAY THROUGH TUESDAY... Friday: MVFR or lower possible in showers. Showers generally expected during the late afternoon/evening. Showers may linger into the overnight. Saturday-Sunday: Mainly VFR. Sunday night-Monday: MVFR or lower possible with chance of showers late at night into early Monday. Tuesday: Mainly VFR. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90 && .MARINE... Light SW flow continues through Thursday with high pressure settling offshore. Winds and seas increase with an approaching cold front Friday and this could lead to a brief period of SCA conditions on some of the coastal ocean waters late Friday afternoon or Friday evening. Confidence remains too low at this time to issue a SCA. Also, model soundings show it being highly inverted across the waters ahead of an approaching cold front. NBM gusts were lowered to 110% of the sustained. Easterly winds pick up on Sunday with gusts possibly approaching 25 kt for a brief time, otherwise winds and seas across all waters are expected to remain below advisory levels this weekend into early next week. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ DISCUSSION...DW AVIATION...BC MARINE...DW