Marine Weather and Tide Forecast for Westhampton Beach, NY

NEAR TERM /UNTIL 6 AM MONDAY MORNING/
Forecast mainly on track tonight. Minor changes made to PoPs to account for latest radar trends, which depict shower activity making their way into Sullivan and Pike Counties, PA. This light rain should enter the CWA/Orange county in the next few hours.
Previous discussion follows.

Vigorous northern stream trough over the Great Lakes swings into W NY/PA by Monday morning. At the surface, a stationary warm front remains draped w to e across northern portions of NYC/LI this evening. Associated surface low over PA tracks ene across the region tonight, with trailing cold front moving through by around daybreak.

Challenging forecast in terms of how far north the warm front pushes through the region this evening. Trend over the last 24 hour has been for slower approach of shortwave and surface wave from the west and slower strengthening of llj, combined with CAD from rain-cooled airmass across Central New England, the warm front will likely have trouble making much progress north of LI and NYC/NJ metro this eve.

Increasing clouds this evening, including stratus across LI and SE CT. Potential for scattered showers tonight as surface low and cold front move thru the region, particularly NW of NYC through this evening ahead of approaching pre-frontal trough and cold front and then across LI/CT overnight with strengthening LLJ. Potential for thunder with cold frontal passage tonight (00z to 09z) is very limited (but non-zero)
with weak elevated instability above 650-750mb capping, and trailing shortwave energy.

Slightly above seasonable temps, particularly coast and east tonight with cloud cover and before caa kicks in Monday. Lows in the mid 50s city/coast, mid 40s well N&W.

SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY/
Closed upper low slides up the St Lawrence River valley Monday into Tuesday, with associated long wave troughing over the eastern 1/2 of the US digging deep into the southern US. At the surface, slow pressure strengthens as it lifts through New England on Monday and stacks under the closed low over SE Canada Mon Night into Tues.

Cold front crosses Mon AM, with reinforcing cold front crossing Mon afternoon. CAA W/NW flow ensues through thru Tuesday under a cyclonic flow regime. Considerable instability cu expected both Monday and Tuesday aft in this regime, with dry conditions outside of an isolated sprinkle with shortwave/secondary cold frontal passage Mon aft. A strong W/NW pressure gradient will result in frequent gusts of 25 to 30 mph on Monday, and 20 to 25 mph on Tuesday.

Highs will likely occur in the morning Monday (upper 50s interior/ lower 60s to 65 city/coast), remaining steady or slowly dropping in the afternoon. Highs on Tuesday (coolest of fall season so far)
likely holding in the lower 50s interior / upper 50s coast which seem reasonable based on 850 hpa temps dropping to -2 to -4C w/ deep mixing.

Mixed low-level Mon Night will keep temps from fully bottoming out, but potential for temps to radiate into the lower to mid 30s across far outlying areas.

LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/
There have been no major changes to the forecast mid week through the end of the week.

*Key Points*

*The coolest temperatures of Fall 2024 will continue Tuesday night into Thursday night.

*A warming trend begins Friday with temperatures returning to normal, then potentially above normal next weekend.

*No precipitation is expected.

The weather pattern will start out with a highly anomalous, positively tilted upper trough over the east coast Tuesday night into Wednesday. 500 mb height anomalies average 2 to 3 standard deviations below normal for this time of year. The trough axis will slowly push offshore by Thursday taking with it any surface cyclogenesis. The trough pushes further out over the Atlantic Friday into next weekend as a large ridge and positive 500 mb height anomalies builds over the east. This will allow the surface high over the central states mid week to build overhead and remain in control Friday into next weekend.

Wednesday will remain breezy with NW flow, fairly deep mixing, and building high pressure off to the west. NW winds may gust 20-30 mph.
The flow then weakens through the end of the week and will remain light next weekend. The coolest day of the period looks to be Wednesday with highs in the lower 50s inland and middle to upper 50s near the coast. These readings are 10-15 degrees below normal for mid October. Highs will begin moderating Thursday and return to normal Friday in the 60s before approaching 70 degrees next weekend.
Lows Tuesday night, Wednesday night, and Thursday night look to fall into the low to mid 30s inland and 40s for coastal/metro areas. This will bring the potential for frost inland, especially where winds weaken or become light Wednesday night and Thursday night.

AVIATION /02Z MONDAY THROUGH FRIDAY/
Mainly VFR except MVFR at KGON and IFR at KSWF with stratus deck north of the warm front. The chance of showers remains at KSWF into late tonight, with a chance at the NYC metro terminals this evening into late tonight.

Low confidence in the wind forecast as a front remains nearly stationary near the terminals, affecting both the wind direction and speed. Gusty W/NW winds develop Monday morning behind the low, with gusts up to 30 kt. LLWS likely at the metros, and KISP/KBDR, as SW winds increase to 40-45 kt at FL020 into the overnight.

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

Uncertainty with the wind forecast, with timing of wind shifting to the south, as this is dependent on a frontal boundary to the south and approach of low pressure to the west tonight through early Monday AM.

OUTLOOK FOR 18Z MONDAY THROUGH FRIDAY...

Monday afternoon: VFR. NW winds 15-20 kt, gusts 25-30 kt, occasionally gusting up to 35 kt. Winds and gusts diminish 10-15 kt, gusts 15-20 kt during the evening, with gusts ending around 06Z Tuesday.

Tuesday and Wednesday: VFR. W-NW winds 10-15G20-25kt.

Thursday through Friday: VFR.

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

MARINE
Easterly winds across LIS this afternoon, switching to SE/S this evening. Otherwise, southerly winds increase to SCA across ocean and southern and eastern bays/sound this evening, and continue into tonight. A brief respite in winds likely overnight as surface low move across, and then SCA gusts expected across all waters Monday behind the cold front. Winds gradually subside Monday Night. In response, waves build to 5 to 8 ft on the ocean late today into tonight, before gradually subsiding Monday night.

SCA gusts appear likely Tuesday night into Wednesday. Winds will weaken Wednesday night and should remain below SCA levels Thursday into Friday with high pressure building over the waters. Ocean seas are expected to remain below 5 ft.

HYDROLOGY
There are no hydrologic concerns through the start of next weekend.

OKX WATCHES/WARNINGS/ADVISORIES
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory from 8 AM to 11 PM EDT Monday for ANZ331- 335-338.
Small Craft Advisory until 11 PM EDT Monday for ANZ332-340-345.
Small Craft Advisory until 2 AM EDT Tuesday for ANZ350-353-355.