Marine Weather and Tide Forecast for North Haven, NY

KEY MESSAGES
1) Isolated to scattered showers with strong wind gusts possible this afternoon into early evening.

2) A period of moderate to heavy rain and embedded thunderstorms likely Sunday afternoon into Sunday night, with additional scattered showers and thunderstorms possible Monday.

DISCUSSION

KEY MESSAGE 1
Surface trough and a shortwave aloft approach this afternoon into evening. Lift from the two features will interact with fairly shallow moisture concentrated in the 850-700mb layer. There will be a chance of showers this afternoon into the evening, but thunderstorm chances appear to be limited with the lack of moisture above 700mb and some capping beneath -10C. Even without convection, showers could produce strong wind gusts with steep low level lapse rates with a dry sub-cloud layer and a wind profile favoring downward momentum transfer. Highest chances of showers will be east of NYC.


KEY MESSAGE 2
Developing low pressure center approaches the forecast area before tracking near/over us late Sunday night into Monday morning.
Potential flooding and strong/severe wind gust impacts will depend on where the storm center tracks, and at this time, guidance leans toward a track over or just south of us. The primary threat therefore appears to be for a period of moderate to heavy rainfall Sunday afternoon/night with approaching shortwave lift and warm front plus a developing 30-40kt llj lifting high moisture (2-2.5" PWAT). The period when flooding would be most likely is mid- afternoon Sunday until around midnight. East of NYC, flooding threat is overall lower due to current FFG values, but heavy rain with a threat of at least minor nuisance/poor drainage flooding would be possible mainly during Sunday night.

An isolated strong to severe thunderstorm threat still exists Sunday afternoon and evening due to the uncertainty of the exact track of the low center in our vicinity. A low track over or to the north of the region would promote high shear/helicity, albeit with weak instability. Still fairly low predictability on thunderstorm coverage and severity at this time. Did not deviate from NBM regarding thunder chances, but it's beginning to look like the chance of severe weather is low and more likely to be confined to the southern half of the forecast area if it were to occur.

Additional iso-sct shower and thunderstorm activity is possible on Monday with a trailing slow cold front, but severe wx does not look likely.

AVIATION /18Z FRIDAY THROUGH WEDNESDAY/
Low pressure trough moves across this evening. High pressure builds thereafter through Saturday.

Mainly VFR conditions are expected through the TAF period. Exception is east of NYC terminals where isolated to scattered showers could develop late this afternoon into early this evening. A thunderstorm will be possible as well. Relatively highest chances of showers at KGON which have a TEMPO group and after that next highest chance of showers at KBDR which has VCSH. Brief MVFR conditions possible with showers.

Winds are transitioning to more southerly flow with sea breezes along coastal terminals. Farther inland, wind direction more westerly flow but variable for some locations. Wind speeds are near 10 kt along the coast, within a 10-13 kt range for some coastal sites while inland wind speeds are generally less than 10 kts.

Winds become more northerly tonight into early Saturday with more sea breeze development expected Saturday afternoon. Wind speeds generally near 5-10 kts.

NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...

Wind speed expected to mainly stay in 9-13 kt range this afternoon.

Wind direction less confidence for TEB. Timing of more southerly flow could be off by 1-2 hours.


OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY

Saturday afternoon through Saturday night: VFR.

Sunday: Mainly VFR in the morning. Increasing potential for MVFR or lower thereafter with showers developing and moving in. Widespread showers, potentially heavy at times at night with potential IFR.
Slight chance of thunderstorms. Southerly wind gusts near 15-20 kt afternoon into night.

Monday: MVFR or lower early with showers. Otherwise, improving conditions throughout the day with eventual return to mainly VFR.

Tuesday: VFR.

Wednesday: Mainly VFR. Chance for showers and MVFR at night.
Southerly wind gusts 15-20 kt afternoon into night.

Detailed information, including hourly TAF wind component forecasts, can be found at: https:/ www.weather.gov/zny/n90

MARINE
Sub-SCA conditions are anticipated through Saturday night in a weak pressure regime.

SCA conditions then appear to become likely Sunday afternoon into Sunday night for the ocean waters, and potentially all waters with strengthening southerly flow ahead of approaching frontal system.
Some gusts could approach gale force depending on the eventual track of low pressure approaching and passing through, but not high enough of a chance for a mention in the HWO.

Rip Currents: A couple of 1 ft S/SE onshore swells, with a weak seabreeze will maintain mainly a low rip risk for the rest of today.
Similar swells conditions with 1-2 ft longshore wind waves will once again result in a low rip risk on Saturday. A recent new moon will continue the wide tidal range, and could increase the rip risk to moderate particularly around the times of low tide today and Saturday.

Rip current risk likely builds to high late on Sunday with strengthening southerly winds and southerly winds waves building to 4-5 ft.

OKX WATCHES/WARNINGS/ADVISORIES
CT...None.
NY...None.
NJ...None.
MARINE...None.