538
FXUS61 KOKX 042245
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
545 PM EST Tue Mar 4 2025

.SYNOPSIS...
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High pressure off the Mid Atlantic coast will slowly move farther offshore through tonight. As strong low pressure moves northeast through the upper Great Lakes region on Wednesday, a pre-frontal trough will approach and move across in the afternoon and evening, followed by a cold front late Wednesday night into Thursday morning. The front will move farther to the east Thursday night, with high pressure gradually building in and passing to the south through Friday. A weak frontal system then passes nearby on Saturday. Another low pressure system should pass well to the south on Sunday as weak high pressure moves in through early next week.
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&& .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
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Only minor adjustments made with this update based on the latest obs and trends. The forecast is mainly on track. Weak warm advection tonight increases toward Wednesday morning, and temperatures are expected to be non diurnal, falling off into late tonight, and then holding steady or slowly rising. With a rather dry column and little forcing do not expect any showers through tonight.
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&& .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... Deep low pressure still expected to pass well to the northwest of the region. passing through the Great Lakes and into southern Canada, Wednesday into Wednesday night. With some increase in isentropic lift Wednesday morning there may be a few scattered showers that move through. However, the area should remain dry until the pre frontal trough approaches by midday. The system will be slow moving with a highly amplified trough and upstream ridge. The warm front may just briefly move through late Wednesday afternoon and be quickly followed by the cold front. Cams are showing a developing line of showers with embedded thunderstorms. Any thunderstorms will be elevated as a low level cap is in place. Any with limited instability and CAPE, thunderstorms may be more isolated. With a strong marine influence thunderstorms east of NYC and across southern Connecticut may be more isolated or may not even occur.The strong southerly flow will bring increased moisture with precipitable water values up to 1.25 inches Wednesday evening, and continues to mention moderate to briefly heavy rain, with rainfall rates up to 1/2 inch an hour, and possibly up to 1 inch per hour. If the heavy rainfall occurs isolated nuisance urban and poor drainage flooding will be possible. Showers will continue once the pre frontal trough moves through. Strong winds are also possible with this system, but with a strong inversion not sure how much mixing will happen, and winds and gusts are likely to remain below wind advisory levels. && .LONG TERM /THURSDAY THROUGH TUESDAY/... High pressure begins to build in slowly during Thursday, however a cyclonic flow aloft with some moisture lingers as a mid level trough shifts through. Only a chance of showers with the overall highest probabilities being north and east of the city and generally in the morning. Winds will shift westerly and increase more noticeably in the afternoon. Thinking is that this downsloping flow combined with partial sunshine and delayed cold air advection will allow for high temperatures to be warmer than deterministic NBM numbers. Went closer to the NBM 75th percentile, which is a few degrees warmer. Highs generally in the 50s. Winds increase further Thursday night with steepening of the pressure gradient, then winds slowly diminish during Friday. W to NW gusts 30-35 mph are expected at night with a few gusts near 40 mph possible. Gusts then gradually lower to 20-25 mph by the end of Friday afternoon. Friday will be mostly sunny with highs mostly 45- 50. Models have trended weaker and farther south with a trough and weak low center Friday night into Saturday morning. Have gone with a dry forecast, but still can`t completely rule out a sprinkle or flurry during this period. Mostly sunny otherwise for Saturday afternoon with highs in the middle and upper 40s. Model consensus then keeps a stronger area of low pressure and associated precip well to our south on Sunday. A fast flow aloft brings uncertainty regarding the timing and strength of weak clipper-type lows or troughs potentially shifting nearby during the Sunday night through Monday period. In any case, moisture is limited, so will go with a dry forecast for the time being. Ridging at the surface and aloft with a SW flow then brings us milder weather for Tuesday. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... High pressure is pushing offshore as a storm system slowly approaches through Wednesday morning. VFR through about 12Z Wednesday, with MVFR developing toward 12-14Z. MVFR is then likely with the chance of IFR, especially at some of the northwest terminals late Wednesday morning. Also, light rain cannot be ruled out, especially northwest of the NYC metro late Wednesday morning into the early afternoon. This was handled with tempo groups for -RA. S winds 10-15 kt with some gusts to 20-25 kt this afternoon. Gusts will drop off 22Z-00Z. S winds should briefly weaken tonight before increasing and becoming gusty Wednesday morning. LLWS is likely at all terminals late tonight into Wednesday. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... Amendments likely with regard to the timing of lowering flight categories Wednesday morning. .OUTLOOK FOR 18Z WEDNESDAY THROUGH SUNDAY... Wednesday afternoon - Wednesday night: MVFR becoming IFR, rain prevails in the afternoon and evening. Isolated thunderstorms possible. LLWS. S winds increasing to 15-25 kt with some gusts around 40 kt, especially south coastal terminals. Peak winds occur for the late afternoon and evening. Winds subside gradually late Wednesday night. Thursday: Mainly VFR. Gusty WNW winds developing in the afternoon, increasing to 15-20 kt G25-35 kt Friday: VFR. W winds G25-30kt. Saturday: VFR with W winds G15-20kt possible. Sunday: VFR with NW / W winds. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90 && .MARINE... With a frontal system impacting the waters Wednesday and Wednesday night a strong southerly flow will continue tonight, and possibly increase Wednesday into Wednesday night. With the cold ocean waters mixing of higher winds aloft will be limited, and have discontinued the gale watch for Long Island Sound and the Long Island eastern bays, and issued a SCA Wednesday into Wednesday night. The strongest winds will be over the near shore ocean waters and continues the gale warning for the ocean, and added the Long Island south shore bays, and New York Harbor. The Harbor may be more marginal, and duration may be shorter than the warning with gusts diminishing Wednesday evening. SCA conds for the ocean on Thursday as seas remain elevated. Winds pick up, and by the end of the day, some of the non-ocean waters could see gusts near 25 kt. A steepening pressure gradient will increase sustained winds and gusts across all waters Thursday night before gradually subsiding through the day Friday. A good chance of W to NW Gales on the ocean for Thursday night into at least Friday morning. Gales possible Thursday night elsewhere, with confidence at least high enough to leave a mention in the HWO. Sub-SCA conds for the non-ocean waters for Friday night, but advisory thresholds will probably still be met on the ocean as winds and seas take longer to subside. Sub-advisory conditions will be likely for the upcoming weekend, but winds and seas on the ocean could be close to criteria at times. && .HYDROLOGY... A frontal system impacting the region Wednesday and Wednesday night should produce QPF of 1/2 up to 1 inch, with locally higher amounts possible. Higher totals are expected inland. Rainfall rates could approach 1/2 inch per hour in spots at the time of heaviest rainfall, which could lead to nuisance urban and poor drainage flooding. No hydrological impacts are expected Thursday through early next week. && .TIDES/COASTAL FLOODING... Astronomical tides will remain low through the end of the week. Intensifying southerly flow ahead of a strong storm system will increase tide levels during the Wednesday night/early Thursday morning high tide. Surge of 1.5 to 3 ft is needed to reach minor flooding benchmarks. The strongest winds may actually occur before high tide, limiting the surge somewhat during high tide. Most locations should remain at or below action stage. However, some of the most vulnerable locations across the south shore back bays and western Sound could touch minor flooding benchmarks. Large breaking waves 8-10 ft are forecast late Wednesday into Wednesday night along the oceanfront, with beach flooding and erosion possible. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...Small Craft Advisory from 6 AM Wednesday to 4 AM EST Thursday for ANZ331-332-335-340. Gale Warning from 6 AM to 10 PM EST Wednesday for ANZ338. Gale Warning from 6 AM Wednesday to 4 AM EST Thursday for ANZ345-350-353-355. Small Craft Advisory until 6 AM EST Wednesday for ANZ350-353- 355. && $$ SYNOPSIS...JC/MET NEAR TERM...MET SHORT TERM...MET LONG TERM...JC AVIATION...JE MARINE...JC/MET HYDROLOGY...JC/MET TIDES/COASTAL FLOODING...