


Area Forecast Discussion
Issued by NWS Upton, NY
Issued by NWS Upton, NY
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709 FXUS61 KOKX 011127 AFDOKX Area Forecast Discussion National Weather Service New York NY 727 AM EDT Mon Sep 1 2025 .SYNOPSIS... A large area of high pressure will prevail from the Great Lakes east into the Mid Atlantic and Northeast states through Tuesday before building offshore Wednesday. High pressure weakens on Thursday, giving way to a frontal system Thursday night into Saturday. High pressure returns on Sunday. && .NEAR TERM /THROUGH TONIGHT/... A pseudo rex block over eastern North America will feature a weak upper low over the Northern Mid Atlantic states, essentially trapped beneath an upper high. Surface high pressure will encompass a large area from the Great Lakes east into the Northeast. Conditions will remain dry, but there will be a canopy of high clouds across the area as the upper low draws moisture northward from a frontal wave well south of the area. The clouds will gradually lift north through the day with the Lower Hudson Valley and eastern portions of CT and LI expected to see the greatest extent, with skies varying between partly and mostly cloudy. Skies are expected to clear across all area tonight. A weak easterly flow will strengthen today as low pressure passes well south and east across the western Atlantic. Daytime highs will be mainly in the mid and upper 70s, which is about 3 to 5 degrees below normal. There will be slightly larger departures tonight with lows in the lower 50s to lower 60s, highest across NYC. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... Upper low opens up and lifts north this period in response to a trough digging south and east across central Canada. High pressure across the area Tuesday will begin to weaken and then moves offshore on Wednesday ahead of a frontal system tracking across the Great Lakes. Expect dry, cool conditions to continue with little change in the vertical temperature profile and a continued maritime influence with an easterly flow. Daytime highs will be in the mid 70s to around 80, with lows Tuesday/Wednesday mainly in the 50s, except the lower 60s for NYC. Lows will come up a bit Thursday morning in a southerly flow. && .LONG TERM /THURSDAY THROUGH SUNDAY/... No significant changes for the long term, so the NBM was closely followed. Key Points: * High pressure weakens on Thursday giving way to a frontal system approaching from the west late Thursday/Thursday night. * The frontal system lingers in the area through at least Saturday with possibly several chances of rain/storms late Thursday through Saturday afternoon. * High pressure with dry conditions expected to build back in from the west by Sunday, lingering into early next week. * Generally below average temperatures expected with high temperatures in the upper 70s to near 80 Thursday through Saturday. Highs drop into the low to middle 70s by Sunday and into early next week. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... High pressure remains just to the north of the terminals through tonight as a weak low pressure system tracks well southeast of the region. VFR. Winds light and variable to a light NE wind this morning becomes ENE and increase 10-15G20kt after 15Z. Winds subside to less than 10 kt this evening. Winds may shift more N tonight. There is a low chance of low stratus development late tonight into early Tuesday morning, mainly in the 8-14Z timeframe. Opted not to include in the TAFs at this time as confidence remains low. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... ENE winds 10-15G20kt likely from mid morning through late afternoon. Confidence in low stratus development late tonight into Tuesday AM remains low. .OUTLOOK FOR 12Z TUESDAY THROUGH FRIDAY... Tuesday through Wednesday: VFR. Thursday: VFR during the day with S gusts 20-25kt in the afternoon. SHRA and possible MVFR at night. Friday: SHRA/MVFR mainly in the morning. S gusts 20-25kt. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90 && .MARINE... Winds and seas will largely remain below SCA criteria under the influence of high pressure through the middle of the week. However, an area of low pressure passing well south and east today into Tuesday will send a building easterly swell into the waters with a chance of 5 ft seas on the ocean Tuesday and Tuesday night. However, guidance continues to stay just below 5 ft during this time frame. E winds will be strongest this afternoon at 10-15kt with gusts to around 20 kt, before diminishing this evening. Seas may return to small craft levels at the end of the week and start of the weekend as a frontal system approaches the waters and low pressure passes nearby. && .HYDROLOGY... There are no hydrologic concerns through the week. && .TIDES/COASTAL FLOODING... The rip current risk should start low today with easterly winds waves generally 2-3 ft around 5-7 seconds, but may increase to moderate late in the day as waves increase to 3 to 4 ft. The risk will likely be moderate on Tuesday as ESE swells building to 3-4 ft at 8-9 seconds. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...DW/MW NEAR TERM...DW SHORT TERM...DW LONG TERM...MW AVIATION...MW MARINE...DW/MW HYDROLOGY...DW/MW TIDES/COASTAL FLOODING...