Marine Weather Net

Fire Island Inlet NY to Moriches Inlet NY out 20 NM Marine Forecast


TODAY

E
WINDS
15 - 20
KNOTS

TONIGHT

NE
WINDS
15 - 20
KNOTS

SAT

NE
WINDS
20 - 25
KNOTS

SAT NIGHT

N
WINDS
15 - 20
KNOTS

The Marine Weather Forecast In Detail:
ANZ353 Forecast Issued: 1120 AM EDT Fri Sep 29 2023

SMALL CRAFT ADVISORY IN EFFECT THROUGH SUNDAY EVENING
Today...E Winds 15 To 20 Kt With Gusts Up To 25 Kt. Seas 6 To 8 Ft. Slight Chance Of Tstms. Showers. Vsby 1 To 3 Nm.
Tonight...Ne Winds 15 To 20 Kt With Gusts Up To 25 Kt. Seas 6 To 8 Ft. Slight Chance Of Tstms. Showers. Vsby 1 To 3 Nm.
Sat...Ne Winds 20 To 25 Kt, Diminishing To 15 To 20 Kt In The Afternoon. Seas 6 To 9 Ft. Rain Likely In The Morning, Then Chance Of Showers In The Afternoon.
Sat Night...N Winds 15 To 20 Kt With Gusts Up To 25 Kt. Seas 6 To 8 Ft. Chance Of Showers, Mainly In The Evening.
Sun...N Winds 15 To 20 Kt, Diminishing To 10 To 15 Kt In The Afternoon. Seas 4 To 7 Ft, Subsiding To 3 To 5 Ft In The Afternoon.
Sun Night...N Winds 10 To 15 Kt. Seas 3 To 5 Ft.
Mon...Ne Winds 10 To 15 Kt. Seas Around 4 Ft.
Mon Night...E Winds 5 To 10 Kt. Seas Around 4 Ft.
Tue...W Winds 5 To 10 Kt. Seas 3 To 4 Ft.
Tue Night...Sw Winds 5 To 10 Kt. Seas 3 To 4 Ft. Winds And Seas May Be Higher In And Near Tstms.
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Area Forecast Discussion
National Weather Service New York NY
1207pm EDT Fri September 29 2023

Synopsis
An inverted surface trough and weak low move northward along the coast today into tonight. The low will slowly strengthen and move east Saturday into Sunday, with high pressure building in its wake and remaining dominant into next week.

Near Term - Through Tonight
***Scattered to Numerous Areas of Flash Flooding remain likely today, with locally considerable to life threatening flash flooding possible***

***Moderate Flooding expected for the Saddle River at Lodi and is possible along a few quick responding small rivers and streams***

There are many flood headlines ongoing across the western parts of the region with flash flooding and river flooding. The area is for parts of Northeast NJ, parts of NYC, parts of the Lower Hudson Valley, and into Southwest CT.

There have already been storm total rainfall reports of near 3 to 6 inches across parts of the Lower Hudson Valley and into parts of NYC. See our latest public information statement for more details on exact rainfall amounts for exact locations.

Current Doppler Radar indicates heavy axis of rain extends from east of Sandy Hook NJ northward through Brooklyn NY, Queens NY, Nassau NY, Bronx NY, Westchester NY, and into Fairfield CT. That is where the heaviest rain is ongoing with rainfall rates between 0.5 and 1.5 inches per hour. Hourly rainfall rates could occasionally reach around 2 inches per hour. The movement is from southwest to northeast, driven by southerly flow of near 10-20 kt from 700 to 500mb. Near the surface, there are NE gusty winds. The structure and dynamics show an environment conducive for back building and training of heavy showers and they will linger around throughout today. So multiple rounds of heavy rain are expected to continue over the next few hours especially across the the aforementioned sections mentioned in the beginning of this paragraph.

Rain across Suffolk County NY and New Haven CT and east across the rest of Southern CT has been light to moderate. Orange County NY is also experiencing less rain, more light rain. The area of concern is in between parts of NYC through Westchester and Fairfield. CAMs show the heavy rain showers shifting gradually and slowly farther east later this afternoon into tonight.

Closed upper low over eastern Great Lakes will slowly approach today, gradually sliding across the area tonight into Saturday. At the surface, an inverted trough sitting off the NJ coast/mid Atlantic coast will extend into NYC, NE NJ, W LI into Lower Hudson Valley vicinity this morning. Evidence of a coastal front/convergence zone across NYC and up Hudson River, which could be a sign of where the inverted trough/coastal front ends up extending into.

Continued good model agreement with increasing deep layered lift from approaching upper low and left front quad of ULJ, combined with a strengthening SE/E LLJ (35-40kt), transporting a sub- tropical(+1-2 STD PWATS) and weakly unstable (a few hundred J/kg of elevated instability) airmass into the region, converging in the vicinity of the inverted trough/coastal front (with likely frontogenetic and orographic enhancement). The environment is certainly primed for deep moist convection and flash flooding type rainfall in the Flood Watch area.

See hydrology sections for more on flood impacts.

In addition to the rain, NE winds of 15-20g25-30mph likely along the coast this morning through Sat AM. A few peak gusts to 35 mph possible. Lighter winds expected for the interior.

High temps will run several degrees below seasonable in rain and onshore flow, and near seasonable for overnight lows.

Short Term - Saturday
As the closed low moves overhead and low pressure becomes more developed tonight into Saturday morning and gradually slides east, the inverted trough/convergence axis will break down and slide east with a more moderate deformation rain on the NW side of the low continuing Tonight into Saturday morning, gradually tapering from w to e.

High temps will run several degrees below seasonable in rain and onshore flow, and near seasonable for overnight lows.

Long Term - Saturday Night Through Thursday
There have been no significant changes to the long term, as global ensemble guidance is in decent agreement with the overall pattern. A rather quiescent and generally dry period is expected along with a warm up into next week.

Closed, positively tilted upper low ejects off the east coast to start, as a an amplified ridge shifts eastward from the Central Plains. The ridge builds to the east Sunday through Wednesday, with the ridge axis overhead by Wednesday. The ridge axis heads offshore Wednesday night.

At the surface, low pressure heads east/southeast of the 40/70 benchmark on Saturday, with lingering showers across the southern portions of the CWA (County Warning Area) though midday. Easterly flow will continue through the day on Saturday, and into early Sunday, keeping coastal sections under cloud cover for a good portion of Saturday, while the interior should see some sun by late afternoon. The pressure gradient begins to relax Sunday as the surface low pulls away and winds become more northeasterly by Sunday afternoon.

A strong high pressure then begins to dominate as it settles over the northeast through Wednesday resulting in mainly dry conditions for the region. Temperatures will be on the increase into midweek, with highs in the mid to upper 70s across the NYC metro, northeast NJ and the interior. At the coasts, highs in the low to mid 70s are expected. Either way, these are near or just above average for the time of year.

Marine
An extended period of SCA (Small Craft Advisory) conds is expected for the ocean into early next week. E/NE SCA (Small Craft Advisory) gusts expected thru Sat, with seas elevating to 7 to 10 ft on E/SE wind swells, as well as background SE swells from a developing offshore low and distant tropical systems impact the coastal waters. E/NE Marginal SCA (Small Craft Advisory) gusts expected on the nearshore waters into Sat AM.

Winds gradually subside Saturday Night through Monday as high pressure builds in from the west.

Hydrology
There have already been reports of near 3 to 6 inches of rainfall across parts of NYC and across parts of the Lower Hudson Valley.

Additional rainfall after 11AM this morning and through early Saturday is forecast to range between 2 and 4 inches across much of the area. Locally greater than 4 inches of additional rainfall after 11AM is forecast especially for parts of Westchester NY, Northern Nassau NY, Fairfield CT. Additional rainfall after 11AM this morning, more in the 1 to 2 inch range for Western Passaic NJ, Orange NY, New London CT, and the Twin Forks of Long Island.

Another consideration is that the period of heaviest rain this AM and thispm will coincide with two high tidal cycles where minor flood thresholds are expected to be reached. This will limit storm drainage capacity for coastal locations during these times and exacerbate flash flood threat in these areas during these times.

Based on the above, scattered to numerous instances of urban, poor drainage, and low-lying flash flooding are likely in the Flood Watch area, with locally considerable/life threatening flash flooding possible.

In addition, river flooding is expected for Ramapo River at Mahwah and Saddle River at Lodi and will be possible for other rivers and streams through tonight.

Tides / Coastal Flooding
An approaching full moon will have rising astronomical tides (as low as 1/4-1/2 ft needed to reach minor thresholds), combined with a persistent and slightly strengthening E-NE flow and E wind wave/swell today into Sat Am will have water levels solidly at minor flood levels (up to 1 1/2 ft inundation) for vulnerable NY/NJ harbor, Jamaica Bay, western Great South Bay, and coastal Westchester/Fairfield communities, with localized minor elsewhere across Long Island and NYC for the high tide cycles through at least Saturday morning.

A bit more uncertainty on how widespread the minor coastal flooding will be with the Saturday night and Sunday morning high tide cycles as astronomical tides peak, but winds turn more to the N-NE and gradually subside. Highest confidence in additional cycles of widespread minor flooding is for the southern bays of Nassau and Queens due to restricted tidal drainage, with perhaps more localized minor flooding elsewhere.

In addition, continued beach erosion/escarpment will continue through at least Saturday due to elevated water levels, 4-7 ft breaking surf, and a strong E-W longshore current. Dune erosion potential looks to be localized, with overwashes not expected.

Although our surf zone forecast season in over, the risk for dangerous rip currents will continue into at least early next week based on the wave conditions.

NOTE: The Peconic River at Riverhead tidal gauge is out of service (had been reading too high). The gauge is being looked into by our partners at the USGS.

NOAA New York NY Office: Watches - Warnings - Advisories
CT...Flood Watch through late tonight for CTZ005-006-009-010. Coastal Flood Advisory until 2pm EDT Saturday for CTZ009. NY...Flood Watch through late tonight for NYZ067>075-078>081- 176>179. Coastal Flood Advisory until 2pm EDT Saturday for NYZ071. Coastal Flood Advisory until noon EDT Saturday for NYZ178-179. NJ...Flood Watch through late tonight for NJZ002-004-006-103>108. Coastal Flood Advisory until noon EDT Saturday for NJZ006-106- 108.

Marine
Small Craft Advisory until 8pm EDT Saturday for ANZ331-332- 335-338-340-345. Small Craft Advisory until 8pm EDT Sunday for ANZ350-353-355.