371
FXUS61 KOKX 052334
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
734 PM EDT Sat Apr 5 2025

.SYNOPSIS...
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A warm front approaches tonight, stalling south of the region, before a cold front pushes through Sunday morning. Low pressure tracks along this stalled boundary Sunday night and exits east Monday. A couple of cold fronts moves through late Monday night and Tuesday afternoon. High pressure briefly builds in Tuesday Night into Wednesday, before pushing offshore Thursday. A slow moving frontal system may affect the area Thursday Night into next weekend.
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&& .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
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Deep SW upper flow across the region, with convectively induced vorticity stream moving into the region ahead of northern stream trough moving east through Ontario/Quebec. At the surface, a weak warm front approaches the area tonight ahead of elongated Tennessee River Valley low pressure moving towards the mid Atlantic, followed by an approaching cold/occluded front late tonight into Sunday Am. Stratus, patchy drizzle and developing fog expected ahead of the warm front this evening with moistening under a strong low level inversion. Patchy dense fog possible over land, particularly near the water. Increasing potential for shower activity and possibly embedded elevated tsra for coastal areas after 10pm with increased theta-e advection and marginal elevated instability along and to the north of the approaching warm front in response to developing low-level jet sliding to the south. This will slide east overnight, with additional rain shower activity sinking se late tonight into Sun morning with se sinking occluded/cold front. Total QPF tonight looks to be around 1/4 to 1/2", but could see isolated higher totals closer to 1-1.5" in any thunderstorms tonight. Gradual moderation in temps expected overnight (rising into the mid 40s interior to lower 50s coast by daybreak) with waa aloft and weakening CAD flow, particularly coastal areas.
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&& .SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/... A cold front, pushes through the area by mid day Sunday. Another round of showers will be possible just ahead of the cold front with a period of dry weather possible later Sunday afternoon and evening. A wave of low pressure will then track along the stalled front and move over the region Sunday night. Rain could be locally heavy at times Sunday night. While some thunder cannot be ruled out, instability looks rather weak which should significantly limit any thunder. Temperatures should be warm enough for mainly liquid precip, but its possible some snow could mix in in the far interior late Sunday night, if temperatures are able to drop low enough. Temperatures on Sunday should warm to the mid to upper 50s. Sunday night will be cold with lows in the low 40s to low 30s. && .LONG TERM /MONDAY THROUGH SATURDAY/... Mean troughing pattern develops across the NE US during the early week and remains through the week, bringing an unsettled start and end to the week. First a northern stream shortwave digging around northern Quebec polar low approaches the region Mon Night, with a ne shearing southern shortwave lifting through, and then moving across Tue/Tue Night. Approaching vorticity and right rear jet lift will help to induce several waves of low pressure along a stationary front to the south of the region Sun Night into Mon. This will have a widespread area of light to moderate overrunning precipitation across the region Sunday night into Monday afternoon, gradually drying out aloft from NW to SE Mon aft/eve in wake of southern shortwave and departing low. Thermal profiles support a rain event for much of the region, except across northern and higher terrain portions of the LoHud and SW CT, where a wet snow/sleet mixture is possible late Sun Night thru Mon AM. Potential for some patchy light slushy accum across highest terrain and mainly grassy surfaces early Mon Am, with surface temps likely at or just above freezing and potential for a 700-800mb warm layer. April sun angle and light precip rates should preclude any localized wintry precip concerns after daybreak. Stratus and patchy fog/drizzle possible Mon Night in wake of frontal waves, and ahead of approaching cold front with low-level saturation but mid-level drying. Temps appear to remain above freezing for the most part, but may have to monitor for some patchy freezing drizzle (patchy black ice with any breaks in stratus) across interior higher terrain as temps drop to around freezing. Cold frontal passage expected late Mon Night/early Tue Am in response to approaching polar short wave, and resultant clipper system moving NE through the St Lawrence River Valley. Drying conditions and caa on gusty NW flow (NW 15-20 gusts 25-35 mph) in wake of initial cold front, and likely secondary polar front Tue aft/eve with polar shortwave passage. Modified polar high builds in and across Tue Night into Wed as upper flow briefly flattens, with potential for widespread sub freezing conds outside of NYC proper Tue Night. Frost/freeze headlines may be needed for NYC/NY metro suburbs where growing season has started. The flatter flow and surface high pressure will be short lived, as a PAC shortwave dives into the central plains and then Ohio Valley Thu/Fri, potentially setting up an anomalous longitudinally deep east coast trough late week into the weekend (with possible 4-5 std below normal 500 MB southern low development at its base). At the surface a resultant Mid-Mississippi River Valley/Ohio Valley low and associated frontal system will likely approach the region late Thu, and then potentially stall near the region Fri thru the weekend (with potential coastal low development) as it becomes aligned with the N/S deepening east coast trough and potential ne lifting southern low. Good general model agreement in the synoptics, but inherent 5-7 day model spread in location/amplitude of trough development, and timing/location/intensity of closed low developing at it base. Which feeds into low predictability on sensible weather details Fri into next weekend. Overall through, potential for an unsettled Fri-Sun. && .AVIATION /00Z SUNDAY THROUGH THURSDAY/...
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A warm front approaches from the south into this evening, stalling in the vicinity overnight. A cold front will then move across the terminals early Sunday morning. Conditions will deteriorate this eve, with LIFR conditions overnight. Periods of RA and DZ will continue tonight. An isolated thunderstorm cannot be ruled out this evening, but the prob is very low attm. The rain ends, along with improving ceilings and visibilities Sunday morning behind the cold frontal passage. Winds become variable with the warm front in the vicinity overnight before shifting to the NW early Sunday morning behind the cold front. Gusts 15-20 kt possible Sunday morning. The flow lightens by the end of the day and into Sun ngt. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... Amendments likely for changing flight categories through tonight. Timing of LIFR tonight may be off by a few hours. Low confidence on exact visibilities overnight. Isolated thunderstorm possible this evening. .OUTLOOK FOR 00Z MONDAY THROUGH WEDNESDAY... Sunday Night-Monday: MVFR-IFR with showers into Monday morning. Wet snow or sleet could mix in at KSWF early Monday morning. Improvement to VFR Monday afternoon. Tuesday: VFR. A slight chance of rain showers in the AM east of NYC metro terminals. W-NW wind gusts 20-30 kt, diminishing at night. Wednesday-Thursday: 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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Dense fog expected on all waters tonight ahead of approaching warm front, with improvement from NW to SE Sun AM in wake of cold front. Otherwise, E/NE SCA winds subside this evening as warm front approaches and gradient weakens, but SCA seas still likely to persist thru the weekend for ocean waters. Marginal 5ft ocean seas may continue on Monday into Monday evening, mainly in a 4-5ft@8 sec S swell, but a weak offshore flow. SCA winds and ocean seas likely on all waters Tue into Tue Night, in wake of a couple of cold fronts. Winds and seas subside below SCA late Tue Night into Wed AM from west to east as high pressure builds into the waters. Sub advisory remain through Thursday as high pressure slide across. Potential for SCA conditions to return for the ocean waters Fri into next weekend, but low predictability at this point.
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&& .HYDROLOGY... There are no hydrologic concerns through next week. && .OKX WATCHES/WARNINGS/ADVISORIES...
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CT...None. NY...None. NJ...None. MARINE...Dense Fog Advisory until 8 AM EDT Sunday for ANZ331-332-335- 338-340-345-350-353-355. Small Craft Advisory until 8 AM EDT Monday for ANZ350. Small Craft Advisory until 11 PM EDT this evening for ANZ353- 355.
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&& $$ SYNOPSIS...20/NV NEAR TERM...20/NV SHORT TERM...20 LONG TERM...NV AVIATION...DS/JMC MARINE...20/NV HYDROLOGY...20/NV