Area Forecast Discussion
Issued by NWS Upton, NY

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386 FXUS61 KOKX 282228 AFDOKX Area Forecast Discussion National Weather Service New York NY 628 PM EDT Tue May 28 2024 .SYNOPSIS... A cold front draped over the region pushes offshore this evening before a second front approaches Wednesday, moving through into Wednesday night. A weak surface trough moves east of the region Thursday. High pressure builds in later Thursday through Saturday night. A weakening low passes slowly to the west and north Sunday through Tuesday. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
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Mid level trough situated over the Great Lakes advances east toward the region and helps scoot a weak cold front farther offshore into tonight. Scattered showers, and isolated thunderstorms, continue over Upstate NY with the approaching trough, but this activity should dissipate this evening once heating ends, and as CAPE decreases along with surface instability. Not out of the question a few showers or an isolated t-storm make it into the Lower Hudson Valley before this, but this should be rather limited in coverage. The HRRR showing that some of this activity does move into Orange and Putnam counties, and may minor adjustments based on this. A gusty west flow lightens early this evening, and updated with the LAV guidance. Dry and mild conditions can be expected tonight as temperatures only fall back into the 60s across the region overnight.
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&& .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
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Trough axis shifts over the Northeast on Wednesday as an embedded shortwave swings through. The cold pool aloft, cyclonic flow, and advancing surface boundary should allow showers to develop into the Lower Hudson Valley by early afternoon, with the activity then spreading east across the rest of the region mid to late afternoon. Despite ample sunshine and a well-mixed BL, conditions appear only marginal for thunderstorm development, with relatively light unidirectional shear, modest CAPE under 1000 J/kg, and surface dew points in the 50s. Still, a few thunderstorms may embed in this activity and advance east into the evening hours. SPC continues to outline the region in a general thunder, which seems reasonable given the above. The front moves through in the evening, and a surface trough lingers as a trailing weak wave of low pressure passes just offshore overnight, keeping a chance for showers into Thursday morning, especially along the coast. QPF from this system will be light outside any heavier convective elements, generally under a quarter inch. Temperatures will be a few degrees cooler than on Tuesday, climbing into the mid to upper 70s for most during the afternoon, or about normal for late May. A general light flow from the west veers more northerly overnight behind the fropa helping to advect drier air into Thursday.
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&& .LONG TERM /THURSDAY THROUGH TUESDAY/...
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An upper level trough from southeastern Canada into the mid Atlantic states will be moving into the western Atlantic during Thursday as a high amplitude ridge builds east from the upper midwest and Great Lakes region. The ridge moves into the western Atlantic Sunday with the flow becoming zonal. A weak, low amplitude shortwave will be moving into the ridge and there will be mainly slight chances of precipitation late Sunday night into Tuesday, mainly inland, where there is better instability and surface convergence. Temperatures will be near to slightly above seasonal normals Thursday into Saturday, with a slight warmup Sunday into the beginning of next week.
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&& .AVIATION /20Z TUESDAY THROUGH SUNDAY/...
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Weak cold fronts will move through the area through tonight. Mainly VFR. Low chance of a pop-up shower this afternoon at KSWF but confidence is low so did not include in the TAFs at this time. Localized brief MVFR cigs possible through early this evening for KSWF. A better chance at seeing scattered showers and TSRA Wednesday afternoon after 20Z. Included in the TAFs as a Prob30. W/NW wind 10-15kt through this afternoon with gusts upwards of 20- 30kt, though gusts closer to 30 kt should be fairly limited. Wind decreases this evening by 01Z to less than 10 kt. NW/W winds around 10 kt continue tomorrow with coastal terminals (KJFK, KISP, KBDR, KGON) becoming more SW due to seabreeze influence in the afternoon. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... No unscheduled AMD expected. OUTLOOK FOR 18Z WEDNESDAY THROUGH SUNDAY... Wednesday: Mainly VFR. Chance of showers and tstms, with brief MVFR or lower cond at times in the afternoon and at night. Thursday: Chance of showers with MVFR cond possible. Friday and Saturday: VFR. Sunday: Mainly VFR. Low chance of MVFR with any rain showers. 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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Westerly flow will continue to occasionally gust up to 25 kt along nearshore waters into early this evening before winds subside. This west wind veers more northerly Wednesday night behind a frontal passage, but winds and seas remain light. Sub-advisory conditions persist Thursday through the weekend with a light flow, generally 10 kt or less.
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&& .HYDROLOGY... No hydrologic impacts are expected through the forecast period. && .TIDES/COASTAL FLOODING...
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There is a moderate rip current risk early Wednesday morning at the Southeast Suffolk ocean beaches, with 3 foot ocean seas and a S to SE swell, with a low risk at the other ocean facing beaches. Thursday there is a low rip current risk at the ocean facing beaches.
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&& .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...DR/MET NEAR TERM...DR/MET SHORT TERM...DR LONG TERM...MET AVIATION...MW MARINE...DR/MET HYDROLOGY...DR/MET TIDES/COASTAL FLOODING...MET