Area Forecast Discussion
Issued by NWS Upton, NY
Issued by NWS Upton, NY
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072 FXUS61 KOKX 170626 AFDOKX Area Forecast Discussion National Weather Service New York NY 226 AM EDT Thu Sep 17 2026 .WHAT HAS CHANGED... No significant changes. && .KEY MESSAGES... 1) Shower chance for this evening / tonight. Low chance of an isolated t-storm N&W. No impacts expected. 2) Lowering humidity during Friday with dry and pleasant weather through Saturday. 3) Wet weather increasingly likely for the second half of the weekend. High uncertainty as to whether it remains unsettled into Monday and Tuesday. && .DISCUSSION... .KEY MESSAGE 1... What is left of an MCS which emanated out of Eastern Ohio slowly migrates east through today. A cold front also moves east and approaches the region into this evening. The CAMs for the most part have been consistent in weakening this activity as it moves east. There remains a chance that the activity may hold together better than advertised by the CAM consensus. If this does happen then it is possible that some t-storm activity gets into far NW and N portions of the area. Thus have slight chance of t-storm towards late day and evening for these sections, otherwise have slight chance to chance showers further east across the area and mainly for the overnight hours. Rainfall amounts overall should be fairly light and under a quarter inch, although locally higher amounts N and NW cannot be completely ruled out in any t-storm. The cold front should move across overnight from NW to SE bringing showers to an end by early Friday morning across eastern sections. .KEY MESSAGE 2... A cooler and drier air mass will gradually work in behind the cold front during the day Friday and into Friday night. Dewpoints are forecast the gradually fall through the 60s during Friday morning, and then through the 50s during the remainder of Friday, and potentially into the middle and upper 40s by late Friday night. This would allow outlying areas to fall into the upper 40s and 50s with respect to minimum temperatures by Saturday morning. With high pressure getting further east during Saturday afternoon and a developing easterly flow daytime temperatures across portions of the area may struggle to get out of the upper 60s to begin the weekend. .KEY MESSAGE 3... During Saturday night as high pressure departs the New England coast a warm front will approach from the west-southwest. This will bring more clouds Saturday night and the likelihood of rain towards Sunday morning. Maintaining likely PoPs and also have categorical PoPs throughout the day Sunday, with PoPs trailing off from NW to SE Sunday night. Afterwards, forecast confidence remains below average at this time with uncertainty around the eventual positioning of the frontal boundary. The latest trend in the NWP global and AI guidance has the boundary getting further south than previous guidance. Thus, Monday may just feature a good deal of clouds with perhaps the bulk of the shower activity remaining south of the area. This theme continues into mid week, with some deterministic guidance bringing rain back into the region later Tuesday. PoPs may have to be raised for Tue and Wed in future forecast packages if the ECMWF guidance is correct. Temperatures during this time period should average slightly below normal, especially daytime temperatures with guidance indicating an onshore northeast to east flow. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... The cold front approaches the region today, eventually crossing through late tonight into early Friday morning. Mainly VFR conditions are expected through the TAF period with exception of KGON. KGON has both some low stratus and fog potential (mainly MVFR) early on in the TAF period early today with otherwise the only other exception being the showers ahead and along the cold front. These showers could briefly result in MVFR conditions mainly for the timeframe of tonight. Regarding winds, generally a southerly flow near 5-10 kt for much of the TAF period. Some terminals will be lighter with winds less than 5 kts along with variable directions into this morning as well as for some time late tonight. For 30 hr TAF sites, they have a wind shift post cold front more to the W-NW with wind speeds near 10 kt into early Friday morning. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... Amendments possible for timing of showers and MVFR which could be off by 1-3 hours. .OUTLOOK FOR 06Z FRIDAY THROUGH MONDAY... Late Tonight: MVFR or lower in any showers that move through, but mainly VFR. Friday: MVFR or lower possible in the morning, but mainly VFR. Saturday: VFR. Saturday Night-Sunday Night: Showers move in late Saturday night, then become widespread on Sunday. A slight chance of thunderstorms. MVFR or lower possible at times. Southerly wind gusts near 15-20 kt Sunday and Sunday night. Monday: MVFR or lower possible with possible showers. NE wind gusts near 15-20 kt. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90 && .MARINE... Mainly sub advisory conditions through today and tonight, although a brief period of 20 kt gusts are likely for the western ocean waters into the western south shore bays late this afternoon and early this evening. Otherwise expect prevailing sub advisory conditions through Friday as the winds turn more out of the north. Towards early Saturday morning marginal small craft gusts of 20 to 25 kt develops on an NE flow. This should subside towards towards the afternoon as the pressure gradient weakens. A better chance at prevailing and more widespread small craft conditions develops during the day Sunday and carrying through much of the time through Monday night. Rip Currents: A moderate risk of rip currents is expected on all ocean beaches today, especially with a SE swell under an increasing southerly wind wave this afternoon. The winds turn offshore and out of the N/NW on Friday. A moderate risk should linger through the morning, with the risk trending towards low later in the day. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ DISCUSSION...JE AVIATION...JM MARINE...JE