Sandy Hook NJ to Fire Island Inlet NY out 20 NM Marine Forecast
|Tonight...W Winds 10 To 15 Kt, Increasing To 15 To 20 Kt With Gusts Up To 25 Kt After Midnight. Seas 2 To 4 Ft.|
|Fri...W Winds 15 To 20 Kt With Gusts Up To 25 Kt. Seas 2 To 4 Ft.|
|Fri Night...Nw Winds 15 To 20 Kt With Gusts Up To 30 Kt. Seas 2 To 4 Ft.|
|Sat...Nw Winds 15 To 20 Kt, Increasing To 20 To 25 Kt In The Afternoon. Seas 2 To 4 Ft.|
|Sat Night...Nw Winds 15 To 20 Kt With Gusts Up To 30 Kt. Seas 2 To 4 Ft.|
|Sun...Nw Winds 15 To 20 Kt, Diminishing To 10 To 15 Kt In The Afternoon. Seas 2 To 3 Ft.|
|Sun Night...Nw Winds 10 To 15 Kt With Gusts Up To 20 Kt, Diminishing To 5 To 10 Kt After Midnight. Seas Around 2 Ft In The Evening, Then 1 Ft Or Less.|
|Mon...Nw Winds 5 To 10 Kt. Seas 1 Ft Or Less.|
|Mon Night...Ne Winds 10 To 15 Kt With Gusts Up To 20 Kt. Seas Around 2 Ft. Chance Of Snow. Vsby 1 To 3 Nm.|
|Tue...Ne Winds 10 To 15 Kt With Gusts Up To 20 Kt. Seas 2 To 3 Ft. Chance Of Snow. Vsby 1 To 3 Nm.|
|Tue Night...N Winds 10 To 15 Kt With Gusts Up To 20 Kt. Seas 2 To 4 Ft.|
| 628 PM EST Thu Jan 21 2021 |
Synopsis for the Long Island Waters and New York Harbor - ANZ300
Weak surface low pressure to our north will send several weak cold fronts across the waters through Friday night. High pressure builds in from the west Saturday and Saturday night, and settles over the region Sunday. The high weakens Monday as low pressure approaches. The low passes south of the area Monday night and Tuesday. High pressure returns for the middle of next week.
| Area Forecast Discussion|
National Weather Service New York NY
710pm EST Thu Jan 21 2021
Weak surface low pressure to the north sends several weak cold fronts through the area by Friday night. High pressure builds in from the west Saturday and Saturday night, and settles over the region Sunday. The high weakens Monday as low pressure approaches. The low passes south of the area Monday night and Tuesday. High pressure returns for the middle of next week.
Near Term - Until 6am Friday Morning
Winds have quickly decoupled and temperatures, especially in the normally colder locations, have fallen quickly, and have been adjusted several degrees lower for current conditions. Increasing cloud cover, and increasing winds toward 06z as another weak trough moves into the region will affect the temperatures. And temperatures will likely rise again in the colder locations as mixing occurs.
During the overnight period, the low pressure to the north of the region will send another weak cold front through the area. This may produce some clouds or some very light passing snow showers for northern portions of the CWA which should end by sunrise.
Short Term - 6am Friday Morning Through Friday Night
More of the same for Friday with a mix of clouds and sun and the potential for some scattered flurries or sprinkles during the afternoon as the low pressure sends yet another weak cold front through the area. The additional mixing from daytime heating and the cold upper-levels thanks to the departing trough will allow for the development of a few convective showers of snow or rain, especially during the afternoon. High temperatures will be seasonable, generally in the low 40s.
Winds then shift more out of the NW by Friday night. The trough shifts eastward as strong high pressure starts to build into the area from the west. The pressure gradient tightens over the area allowing brisk winds with gusty conditions developing through Friday night and into early Saturday. Lows on Friday night will generally be in the 20s with some of the coldest spots dropping into the teens.
Long Term - Saturday Through Thursday
The northern stream will remain dominate and progressive through the weekend and into Monday. A ridge builds into the northeast and mid Atlantic coast by Sunday and then weakens as a northern stream trough moves into eastern Canada Sunday night and Monday.
A cold airmass will be in place for Saturday with a gusty northwest flow as temperatures are expected to be a few degrees below seasonal normals, with wind chills in the teens and lower 20s. Saturday night the gusty northwest flow gradually diminishes as the cold airmass remains and temperatures will be around 5 degrees below normal. Wind chill values will be mostly in the single digits.
Meanwhile a southern stream shortwave moves out of the southwest and quickly reaches the mid Atlantic coast Tuesday. There is some phasing of the northern and southern stream Tuesday into Tuesday night, however, the southern stream surface low will dominate as the surface low reaches the Ohio Valley by 00Z Tuesday. There remain some differences in the guidance with the timing and placement of another low developing off the mid Atlantic coast Monday night and tracking east into the Atlantic through Tuesday night. The trends remain to keep the low to the south of the area as arctic high pressure to the north noses down along the northeast coast. The ECMWF (European Centre for Medium-Range Weather Forecasts) continues to be the furtherest north with the low, while the GFS and Canadian keep the precipitation shield across the southern portions of the forecast area. Will keep the probabilities at chance throughout the region for late Monday night through Tuesday. The airmass remains cold and precipitation is expected to be in the form of light snow.
Thereafter high pressure returns for later Tuesday into Thursday. And the is a chance another low moves south of the area late Thursday.
The SCA (Small Craft Advisory) for the eastern Long Island Sound, and the Long Island bays was allowed to expire as winds have decoupled and fallen well below 25 kt.
Small craft conditions on the oceans will persist through at least Friday night with gusty winds over 25 kt becoming more persistent through the day Friday and continuing into the night. The SCA (Small Craft Advisory) for the ocean was extended through Friday night.
Small craft conditions will be on going for Saturday across all the forecast waters, with a strong northwest flow. There will even be a chance of gales across the eastern ocean waters late Saturday afternoon into the early evening.
High pressure will build in slowly from the west Saturday and Saturday night, and wind gusts will be gradually diminishing below SCA (Small Craft Advisory) levels Saturday night through Sunday, with ocean seas below SCA (Small Craft Advisory) by late day Sunday. Sub advisory conditions are then expected across all the waters from late Sunday night through Tuesday night as high pressure gradually weakens with approaching low pressure to the south.
Mainly dry conditions are expected through the upcoming weekend. No hydrologic concerns are anticipated through the middle of next week.
NOAA New York NY Office: Watches - Warnings - Advisories
CT...None. NY...None. NJ...None.
Small Craft Advisory until 6am EST Saturday for ANZ350-353- 355.