New York Harbor Marine Forecast
|Today...N Winds 5 To 10 Kt, Becoming Se This Afternoon. Waves 1 Ft Or Less.|
|Tonight...Se Winds 10 To 15 Kt With Gusts Up To 20 Kt, Diminishing To 5 To 10 Kt After Midnight. Waves 1 To 2 Ft This Evening, Then 1 Ft Or Less.|
|Thu...Se Winds 10 To 15 Kt With Gusts Up To 20 Kt, Becoming W 20 To 25 Kt With Gusts Up To 30 Kt In The Afternoon. Waves 1 To 2 Ft. Chance Of Showers In The Morning, Then Showers And Tstms In The Afternoon With Vsby 1 To 3 Nm.|
|Thu Night...W Winds 15 To 20 Kt, Increasing To 20 To 25 Kt With Gusts Up To 30 Kt After Midnight. Waves 2 To 3 Ft.|
|Fri...W Winds 20 To 25 Kt With Gusts Up To 35 Kt. Waves 2 To 3 Ft.|
|Fri Night...Nw Winds 20 To 25 Kt, Becoming W 15 To 20 Kt After Midnight. Waves 2 To 3 Ft.|
|Sat...W Winds 15 To 20 Kt. Waves Around 2 Ft.|
|Sat Night...Nw Winds 10 To 15 Kt, Becoming N 5 To 10 Kt After Midnight. Waves 1 To 2 Ft In The Evening, Then 1 Ft Or Less.|
|Sun...Se Winds 5 To 10 Kt, Increasing To 10 To 15 Kt In The Afternoon. Waves 1 Ft Or Less, Then 1 To 2 Ft In The Afternoon.|
|Sun Night...S Winds 10 To 15 Kt, Becoming Se 15 To 20 Kt After Midnight. Waves 1 To 3 Ft. Rain Likely With Vsby 1 To 3 Nm. Winds And Waves Higher In And Near Tstms.|
Area Forecast Discussion|
National Weather Service New York NY
957am EDT Wednesday April 8 2020
Low pressure will pass to the east today, followed by weak high pressure tonight. A cold front will move through on Thursday. Associated low pressure will pull away into the Canadian Maritimes on Friday, followed by high pressure building from the west on Saturday. Low pressure will then approach from the west on Sunday and impact the area Sunday night into Monday.
Near Term - Until 6pm This Evening
Expecting mainly dry conds today, but with plenty of low level moisture trapped beneath an inversion resulting in a partly to mostly cloudy sky today, with the 11Z RAP/HRRR (High-Resolution Rapid Refresh) showing only potential for a shower or two across Long Island this afternoon. Some clearing may occur late on a N-NW flow. This will allow temperatures to rise into the upper 50s and lower 60s.
Short Term - 6pm This Evening Through Thursday Night
Weak ridging will result in a quiet night ahead of another system which will impact the region during the day on Thursday. Lows Wednesday night will be in the 40s under a partly to mostly cloudy sky.
On Thursday, a strong shortwave will dive out of the Great Lakes with a surface low tracking out of Canada into the northeast. This low will drag a strong cold front through the area, likely sometime from late morning through the mid afternoon. A strong jet developing just to the south will provide deep-layer shear and strong lift, however instability continues to look marginal at this time. Even with low CAPE, strong dynamics aloft will likely result in a line of showers with embedded thunderstorms moving through in the early afternoon. The biggest threat with these showers and storms would be gusty winds.
Immediately following the frontal passage, the sky will clear and we should mix out. BUFKIT soundings are indicating a period of gusty winds of 30 to 35 mph during the afternoon and into the overnight.
Long Term - Friday Through Tuesday
To start, expect brisk conds on Fri, with isold-scattered showers as low pressure pulls away. Inland sections especially the higher elevations could see some snow mixed in during the morning. W-NW winds will be on the brisk side due to the departing low's tight pressure gradient, so expect winds at or near advy criteria in the greater NYC metro area and across Long Island, and possibly elsewhere.
High pressure then builds across Sat into Sat night. Guidance shows more northern stream interaction with a southern stream low pressure system approaching for Sunday into Mon, and so have gone with its slower trend. That guidance is also decidedly wetter and windier, which makes sense given the strengthening offshore high and long S fetch, at least per ECMWF. GFS fcsts a secondary low to develop along the coast which, if it develops, would probably result in a stout E-SE rather than S flow. Given the very good warmth/moisture transport via either a S fetch or enhanced convergence/lift via a secondary low, heavy rain also looks like a good bet, with axis of heaviest rain a little to early to know for certain.
Temps about 5-8 deg below normal on Fri, with highs in the lower/mid 50s, will moderate somewhat on Sat to mid/upper 50s, still slightly below avg. Temps on Sunday/Monday ahead of the approaching low should warm up, with upper 50s to mid 60s on Sunday, and 60s to lower 70s on Mon, highest away from the coast.
Quiet today as low pressure passes east, with only a 2-ft ocean swell at most.
A strong frontal system will then impact the waters on Thursday, preceded by a strengthening S flow that will likely bring at a minimum SCA (Small Craft Advisory) conditions to the ocean waters by late morning. This will be short-lived though as a strong cold front works across the waters in the afternoon with the potential for westerly gusts to approach gale force.
As low pressure rapidly deepens over northern New England Thursday night, westerly gales will likely develop across all waters and continue into Friday with gusts up to 40 kt.
Winds will gradually diminish Friday night into Saturday with SCA (Small Craft Advisory) conditions for much of the period. High pressure will build across the waters Saturday night.
Increasing S flow between a strengthening offshore high and approaching low pressure may bring SCA (Small Craft Advisory) conds to all waters Sunday night. Some gale force wind gusts may be possible on the ocean waters late.
Wetting rains on Thu should help limit fire growth potential on Fri despite strong winds and low afternoon RH. With some drying out Sat could be a day of concern, with W winds still gusting to 30 mph and min RH 20-30%.
No hydrologic impacts are expected from the showers impacting the area this morning.
A quarter to a half an inch of rain is expected Thursday, but locally higher amounts could be realized. Low chance of minor nuisance flooding on Thursday.
Quantitative Precipitation Forecast for the low pressure system Sunday night into Monday has trended wetter, with amts of 1-2 inches forecast. This may be capable of causing some minor areal and small stream issues.
Tides / Coastal Flooding
High astronomical tides due to the supermoon and a positive tidal anomaly will be factors for the total water level forecast through Wednesday. Winds will not be strong, about a 10 kt onshore flow or less, so tidal piling and wind forcing will not be too much, limiting the coastal flood potential.
Hazards are as follows:
Tonight through Wednesday: Coastal flood statements across much of the shorelines of NY Harbor, Western Long Island Sound, and South Shore Bays. The total water level will be around 1/2 to 1 foot above astronomical tides, so about 1/2 to 1 foot of surge during times of high tide. Isolated minor coastal flooding will be the result.
Wednesday Night: Coastal flood advisories for the more vulnerable coastal locations across NY Harbor, Western Long Island Sound, South Shore Bays and SW Suffolk NY. The total water level will be 1 to 2 feet above astronomical tides, so about 1 to 2 feet of surge during times of high tide. Widespread minor coastal flooding will be the result. Other nearby locations such as Eastern Union NJ, Eastern Essex NJ, Manhattan, Bronx, Northern Queens will get close to touching minor coastal flood benchmarks. These less exposed coastal locations have a coastal flood statement for Wednesday night, more of an isolated minor coastal flood situation.
Minor coastal flooding potential remains on Thursday with astronomical tides still being high. There will also be a strong cold front approaching that will bring increased onshore winds during the day. Much lower total water levels occur Thursday night into Friday as winds strengthen out of the west, a stronger offshore flow overall. Any lingering coastal flood threat diminishes rapidly Thursday night.
NYC NOAA Weather Radio Station KWO35 (162.55 MHz) is undergoing its final stages of testing, and is operating at full power.
NOAA New York NY Office: Watches - Warnings - Advisories
CT...Coastal Flood Advisory from 11pm this evening to 2am EDT Thursday for CTZ009-010. NY...Coastal Flood Advisory from 11pm this evening to 2am EDT Thursday for NYZ071-078-177. Coastal Flood Advisory from 8pm to 11pm EDT this evening for NYZ074-075-178-179. Coastal Flood Advisory from 10pm this evening to 1am EDT Thursday for NYZ080. NJ...Coastal Flood Advisory from 8pm to 11pm EDT this evening for NJZ006. MARINE...Gale Watch from Thursday evening through Friday afternoon for ANZ330-335-338-340-345-350-353-355. Small Craft Advisory from noon to 6pm EDT Thursday for ANZ330- 335-338-340-345-350-353-355.