Long Island Sound West of New Haven CT / Port Jefferson NY Marine Forecast
|Tonight...N Winds 5 To 10 Kt, Becoming Nw 10 To 15 Kt With Gusts Up To 20 Kt Late. Seas 1 Ft Or Less, Then Around 2 Ft After Midnight.|
|Thu...Nw Winds 15 To 20 Kt With Gusts Up To 30 Kt. Seas Around 2 Ft.|
|Thu Night...Nw Winds 15 To 20 Kt. Gusts Up To 25 Kt In The Evening. Seas Around 2 Ft. Chance Of Rain.|
|Fri...N Winds Around 15 Kt With Gusts Up To 25 Kt. Seas Around 2 Ft. Chance Of Rain.|
|Fri Night...N Winds 10 To 15 Kt With Gusts Up To 20 Kt. Seas Around 2 Ft In The Evening, Then 1 Ft Or Less.|
|Sat...Ne Winds 5 To 10 Kt. Seas 1 Ft Or Less.|
|Sat Night...S Winds 5 To 10 Kt. Seas 1 Ft Or Less.|
|Sun...S Winds 5 To 10 Kt. Seas 1 Ft Or Less.|
|Sun Night...S Winds 5 To 10 Kt, Becoming Sw After Midnight. Seas 1 Ft Or Less.|
|Mon...W Winds 5 To 10 Kt. Seas 1 Ft Or Less.|
|Mon Night...W Winds 5 To 10 Kt. Seas 1 Ft Or Less.|
Area Forecast Discussion|
National Weather Service New York NY
338pm EDT Wednesday April 1 2020
Deep low pressure will continue moving away from the Eastern Seaboard this evening before lifting northeastward tonight. The low then meanders well south and east of Long Island Thursday through Friday night. High pressure will build across the area this weekend before a weak cold front crosses the area Sunday night. High pressure then briefly returns on Monday, followed by an approaching frontal system for the middle of next week.
Near Term - Until 6am Thursday Morning
A strong and well organized low pressure off the North Carolina coast will continue moving offshore tonight. The low will get captured by the large upper low/trough that is situated over the Eastern Seaboard.
The region will lie in subsidence tonight with dry conditions. Skies will be partly cloudy for much of the area. Moisture will continue to get pulled down the New England coast and move over Eastern Long Island and Southeastern Connecticut. This is where the highest sky cover is forecast.
Lows will be in the lower and middle 30s for most locations except for around 40 degrees in the NYC metro.
Short Term - 6am Thursday Morning Through Friday
The deep low offshore will lift north Thursday morning and then begin to retrograde westward as it becomes vertically stacked. A blocking regime across the North Atlantic and Southeast Canada will also help retrograde the whole system westward through Thursday night. On Friday, the system gradually shifts southward and then away from the coast once again.
Thursday will begin dry for the entire area. Clouds will gradually increase from east to west through the day as moisture from the offshore low begins to advect towards the region. Some rain bands are likely to be located to our east early in the morning. These rain bands will retrograde westward, especially in the afternoon and evening. It may take some time for the rain to make it across Eastern Long Island and Eastern Connecticut as they will encounter subsidence on the backside of the system. Middle level thermal forcing increase in the evening and this is when the highest probability for rain exists mainly east of the Hudson River. The rain bands should gradually weaken overnight Thursday into Friday morning as the forcing wanes. However, low and middle level moisture is going to hang around through Friday so some areas of light rain cannot be ruled out. Areas west of the NYC metro may largely stay dry as the retrograding rain bands encounter stronger subsidence to the west. Probabilities for rain decrease from west to east on Friday.
The pressure gradient between the offshore low and high pressure to the west will bring breezy conditions both Thursday and Friday. Wind gusts 25-30 mph are likely Thursday with potential for a few gusts up to 35 mph near the coast. Winds may weaken a bit Thursday night, but increase again Friday, especially across Eastern Long Island and Southeast Connecticut.
Temperatures will be near to slightly above normal for the end of the week.
Long Term - Friday Night Through Wednesday
The surface and upper lows finally begin to pull away to the east Friday night. After a lingering chance of showers early across portions of Long Island and southeastern Connecticut, dry weather will return overnight along with gradually decreasing clouds. High pressure then builds across the region for the weekend, resulting in dry and at least partly sunny conditions.
Clouds will gradually increase Sunday afternoon as a weakening cold front approaches from the west. With the front weakening as it reaches the area, rain chances look fairly limited at this time, but think a few showers are possible Sunday evening into Sunday night. High pressure then briefly builds back across the area on Monday before the weather turns unsettled for the middle of the week as a frontal system approaches the area Tuesday into Wednesday. Numerous model differences remain in the timing and evolution of this system. For now have rain chances gradually increasing through the day on Tuesday with better chances on Wednesday, but it is likely that at least a portion of this period will remain dry.
After near normal highs on Saturday, temperatures through the remainder of the long term period will generally be above normal. Daytime highs will range from the low to mid 50s along the immediate south facing coasts to the low to mid 60s for NYC and areas north and west. Overnight lows will generally remain in the 40s.
Strong low pressure continues moving off the Carolina Coast tonight and then northeast on Thursday. The low then meanders south and east of Long Island into Friday. SCA (Small Craft Advisory) conditions, mainly in seas, will continue on the ocean waters tonight. Winds increase on all waters to SCA (Small Craft Advisory) levels Thursday into Thursday night. Winds on the non-ocean waters likely fall below SCA (Small Craft Advisory) levels Thursday night. SCA (Small Craft Advisory) conditions are then likely on the ocean waters and possibly Eastern LI Sound, and Eastern LI Bays on Friday. Gales are also possible on the waters east of Moriches Inlet Friday.
While winds will gradually decrease through the night, gale conditions may linger into Friday night on the ocean east of Moriches Inlet, with SCA (Small Craft Advisory) gusts possible for portions of the eastern Long Island Sound, Peconic and Gardiners Bays, and the ocean waters west to Fire Island Inlet. Winds should then fall below SCA (Small Craft Advisory) criteria on all waters Saturday morning, although seas will remain elevated on the ocean through the day on Sunday. Conditions are then expected to remain below SCA (Small Craft Advisory) levels on Monday.
No hydrologic impacts are expected through the middle of next week.
Tides / Coastal Flooding
Minor coastal flooding benchmarks may be reached for Friday morning and Friday evening high tide cycles. The greatest potential for this to occur is for the South Shore Back Bays, with a lower risk across the Western Long Island Sound. More widespread minor coastal flooding is possible for Saturday mornings high tide.
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...None. NY...None. NJ...None.
Small Craft Advisory from 8am to 10pm EDT Thursday for ANZ330-335-338-340-345. Small Craft Advisory until 6am EDT Friday for ANZ350-353-355. Gale Watch from Friday morning through late Friday night for ANZ350.