000
FXUS61 KOKX 302042
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
342 PM EST Tue Jan 30 2024

.SYNOPSIS...
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An upper level disturbance moves across the region tonight into Wednesday morning. High pressure will otherwise remain over New England into Wednesday night. A cold front approaches from the north and west Thursday, moving through Thursday night. High pressure then gradually builds in from Southeastern Canada Friday and remains in control into the beginning of next week.
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&& .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
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A ridge axis this evening will give way to a shortwave late tonight into early Wednesday. Surface high pressure over the New England coast will largely remain in place tonight, but the flow around the high will continue becoming a light SE. The combination of the approaching shortwave and onshore/upslope flow appear enough to support lift for some snow showers across NE NJ and portions of the Lower Hudson Valley. Most of the 12z hi-res guidance has a light reflectivity and light qpf signal in these areas. The main concern revolves around the level of saturation aloft for snow growth. The moisture layer is shallow with a dry slot above about 6-7kft. The upslope flow should be enough of a lifting mechanism to generate precipitation and the SE flow off the ocean should provide condensation nuclei for snow. While the dendritic snow growth zone is dry, there appears to be just enough saturation between -7 to -9C to support small snow crystals likely in the form of needles. If the saturation layer is thinner, then it may be more difficult for snow to grow in which case some light rain/freezing rain is possible. Temperatures for the most part should fall to freezing or just below away from the urban NE NJ corridor. Light freezing rain is not currently mentioned, but is something that will need to be monitored if snow growth is less than anticipated. The focus for snow showers should mainly be west of the NYC metro, but there could be some flurries or brief snow showers nearby overnight. Have bumped PoPs up to chance for NE NJ and portions of Lower Hudson Valley tonight given the latest trends. Any snow accumulation looks to be on the light side and under an inch. Otherwise, overcast conditions will continue tonight with moisture trapped below a subsidence inversion. Lows will range from the middle to upper 20s inland and eastern Long Island to the lower to middle 30s elsewhere.
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&& .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
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The axis of the shortwave will shift south and east of the area Wednesday morning. Any lingering snow showers in NE NJ/Lower Hudson Valley should dissipate shortly after 12z. Heights will begin rising behind the shortwave with ridging building through Wednesday night. High pressure will remain in control at the surface. The main challenge for the rest of Wednesday will be with the amount of cloud cover. Model soundings continue to indicate a subsidence inversion between 4-5kft. Consensus blends are showing some improvement with the amount of cloud cover in the afternoon, especially across Long Island and southeast Connecticut. However, given recent trends with guidance too quick to improve sky conditions have gone with a mostly cloudy forecast on Wednesday. There is not much difference with soundings Wednesday night and will continue with mostly cloudy conditions. Highs will be close to normal in the upper 30s inland and lower 40s near the coast. Temperatures Wednesday night will be in the upper 20s inland and lower 30s near the coast.
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&& .LONG TERM /THURSDAY THROUGH TUESDAY/...
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A weak cold front and low pass through the region Thursday into Thursday night with slightly above normal temperatures. Then, the remainder of the long term period, Friday into the beginning of next week, will be tranquil, with near normal temperatures, as high pressure builds in from Central Canada Friday and remains through Tuesday. The forecast remains very similar with the previous forecast as a weakening northern stream surface low and upper shortwave approach from central Canada early Thursday, with the low moving to the east and the cold front passing through Thursday night. The upper trough does begin to amplify late Thursday night into Friday as the cold front moves to the south and east of the region. There is very little lift ahead of and with the cold front, and moisture is limited to the lower levels. Continuing with the slight chance probabilities, and with the warm temperature profiles, light rain showers or sprinkles will dominate. Thursday night, in the colder air, some snow showers, or flurries may mix in with the rain before coming to an end. Canadian high pressure then builds in Friday and remains into the beginning of next week.
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&& .AVIATION /20Z TUESDAY THROUGH SUNDAY/...
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High pressure slowly builds down the New England coast while an upper level disturbance approaches tonight into Wednesday morning. Ceilings will generally vary between 3000-3500ft into early this evening before becoming predominantly MVFR tonight. KGON is expected to stay VFR through the period. There is also a chance of IFR tonight in snow showers at KEWR, KTEB, and KSWF. Most sites will then become VFR late Wednesday morning or afternoon. Winds will veer to the ESE at less than 10 kt this afternoon. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... Ceiling will likely fluctuate between 3000-3500 ft this afternoon/early this evening. Chance of IFR in snow showers tonight, especially at KTEB and KEWR. OUTLOOK FOR 18Z WEDNESDAY THROUGH SUNDAY... Wednesday Afternoon: VFR or becoming VFR. Wednesday Night through Thursday: VFR. SW winds G15-20kt Thursday afternoon. Thursday Night and Friday: Chance of MVFR or lower conditions in rain showers, possibly mixing with SN Fri. NNW winds G15-20kt Friday. Saturday and Sunday: VFR. 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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Long period E-SE swells will continue through Wednesday night on the waters. Seas are starting to subside below 5 ft and have cancelled the SCA west of Fire Island Inlet. The SCA remains in effect from Fire Island Inlet to Moriches Inlet until 6 pm and have extended east of Moriches Inlet until 10pm. Winds on the waters will remain below SCA levels with a weak pressure gradient in place through Wednesday night. Marginal SCA conditions are possible on the ocean waters Thursday ahead of a cold front, in a southwest flow. Then behind the cold front Friday night into early Saturday SCA gusts will be possible on the ocean waters in a northwest flow. Winds and seas remain below advisory levels across all the waters late Saturday through early next week as high pressure remains in control.
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&& .HYDROLOGY...
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No hydrologic impacts are expected into early next week.
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&& .OKX WATCHES/WARNINGS/ADVISORIES...
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CT...None. NY...None. NJ...None. MARINE...Small Craft Advisory until 10 PM EST this evening for ANZ350. Small Craft Advisory until 6 PM EST this evening for ANZ353.
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&& $$ SYNOPSIS...DS/MET NEAR TERM...DS SHORT TERM...DS LONG TERM...MET AVIATION...DW MARINE...DS/MET HYDROLOGY...DS/MET