Massachusetts and Rhode Island · Wednesday, Sep 23

Nantasket Beach

Updated Tue, Sep 22, 8:30 PM EDT

When to go

7:00 AM–9:00 AM

Strong wind — difficult conditions · Low confidence

3.6–3.8 ft · Offshore waves · not face height

Strong wind: 15.0 kt · onshore

Cautions

Strong wind or gusts up to 23.1 kt can make the session difficult; being first in the list does not make conditions good.
Strong wind or gusts up to 23.3 kt can make the session difficult; being first in the list does not make conditions good.
Strong wind or gusts up to 23.7 kt can make the session difficult; being first in the list does not make conditions good.

Forecast details

This is the best time in the forecast, though wind may make it choppy.

Other wind windows

Plan around the wind

The best available upcoming daylight wind sample to compare with the wave evidence. This compares wind only; wave size, tide suitability, and hazards can change your choice.

7:00 AM–9:00 AM · America/New_York
Strong wind · up to 15.0 kt · reported gusts up to 23.7 kt
Caution: This is the best available wind comparison, not a favorable-wind label. Strong wind remains in the selected evidence.
Offshore waves: 3.6–3.8 ft across the period. Surf height unavailable. Tide data available; check the local tide response.
Wind source time: Sep 22, 7:45 PM EDT. This is not the model run issue time.

How these periods are chosen

The planner prefers three consecutive hourly samples covering two daylight hours, but retains shorter one- or two-sample evidence when that is all the forecast provides. Light wind means at most 6 kt. Moderate offshore means at most 12 kt from land toward the sea when shore orientation is verified. Strong wind or known gusts of 20 kt or more remain visible as cautions instead of making the entire comparison disappear. These are comparison labels, not locally tested surf-quality or safety ratings. Missing gusts remain unknown. Terrain shelter, currents, closures, and your ability are not assessed.

Forecast confidence

Returned marine grid point is 7.2 km from the mapped spot. Provider grid resolution is not established for this response.
Reference model hour: 11 hours from now; historical residuals do not measure forecast lead-time error.
No accepted local model for these inputs: missing history, unsupported direction/period/height, or failed historical validation.
A mapped coordinate does not establish nearshore grid resolution or terrain/shelter accuracy.

Wind NE 14.1 kt

Tide 7 ft rising

Wave, wind and tide details

Offshore model swellE 1.7 ft @ 6sValid 2026-09-23 08:00 · America/New_YorkMarine grid 42.3750, -70.8750 · offshore model, not a local measurement

Offshore model sea3.7 ft @ 5sSignificant wave height including wind waves and swell; not breaking surfValid 2026-09-23 08:00 · America/New_York

Model windNE 14.1 ktonshoreValid 2026-09-23 08:00 · America/New_York11.0 kt onshore component

Tide7 ftrisingBoston station 8443970 · predicted height relative to MLLWRetrieved Sep 22, 8:31 PM EDT · provider issue time unavailable74% of adjacent local low–high range · descriptive, not a safety rating

Surf height unavailable. Coastal and offshore waves are not breaking-wave heights.

Surf and wind

Recommended window: No recommended window

Breaking surf is not reliably resolved. Hourly offshore swell and wind inputs are listed below.

Hourly forecast

Hourly surf forecast for Nantasket Beach
Time	Wind	Tide	Offshore swell
12 AM	NE 11.3 ktonshore	5.5 ftfalling	E 2.0 ft @ 5s
1 AM	NE 12.4 ktonshore	4.5 ftfalling	E 2.0 ft @ 5s
2 AM	NE 12.9 ktonshore	3 ftfalling	E 2.0 ft @ 5s
3 AM	NE 14.3 ktcross-shore	1.5 ftnear low	E 2.0 ft @ 5s
4 AM	NE 14.4 ktcross-shore	2 ftrising	E 2.0 ft @ 5s
5 AM	NE 14.9 ktcross-shore	3 ftrising	E 2.0 ft @ 5s
6 AM	NE 13.7 ktonshore	4.5 ftrising	E 1.9 ft @ 5s
7 AM	NE 13.2 ktonshore	5.5 ftrising	E 1.8 ft @ 6s
8 AM	NE 14.1 ktonshore	7 ftrising	E 1.7 ft @ 6s
9 AM	NE 15 ktonshore	8 ftrising	E 1.8 ft @ 6s
10 AM	NE 16 ktonshore	8.5 ftfalling	E 1.8 ft @ 6s
11 AM	NE 16.2 ktcross-shore	7 ftfalling	E 1.9 ft @ 6s
Noon	NE 16.6 ktcross-shore	6 ftfalling	E 2.0 ft @ 6s
1 PM	NE 17.9 ktcross-shore	4.5 ftfalling	E 2.2 ft @ 6s
2 PM	NE 17.2 ktonshore	3.5 ftfalling	E 2.3 ft @ 6s
3 PM	NE 17.2 ktcross-shore	2.5 ftnear low	E 2.4 ft @ 6s
4 PM	NE 17.2 ktcross-shore	2 ftrising	E 2.4 ft @ 6s
5 PM	NE 16.6 ktonshore	3.5 ftrising	E 2.5 ft @ 6s
6 PM	NE 15.7 ktonshore	4.5 ftrising	E 2.6 ft @ 6s
7 PM	NE 14.8 ktonshore	6 ftrising	E 2.6 ft @ 6s
8 PM	NE 14.3 ktonshore	7.5 ftrising	E 2.6 ft @ 6s
9 PM	NE 14.2 ktonshore	8.5 ftrising	E 2.8 ft @ 6s
10 PM	NE 14.2 ktonshore	9.5 ftfalling	E 2.9 ft @ 6s
11 PM	NE 14.4 ktonshore	8 ftfalling	E 3.0 ft @ 6s

12 AMUnavailable

WindNE 11.3 ktonshoreTide5.5 ftfallingOffshore swellE 2.0 ft @ 5s

1 AMUnavailable

WindNE 12.4 ktonshoreTide4.5 ftfallingOffshore swellE 2.0 ft @ 5s

2 AMUnavailable

WindNE 12.9 ktonshoreTide3 ftfallingOffshore swellE 2.0 ft @ 5s

3 AMUnavailable

WindNE 14.3 ktcross-shoreTide1.5 ftnear lowOffshore swellE 2.0 ft @ 5s

4 AMUnavailable

WindNE 14.4 ktcross-shoreTide2 ftrisingOffshore swellE 2.0 ft @ 5s

5 AMUnavailable

WindNE 14.9 ktcross-shoreTide3 ftrisingOffshore swellE 2.0 ft @ 5s

6 AMUnavailable

WindNE 13.7 ktonshoreTide4.5 ftrisingOffshore swellE 1.9 ft @ 5s

7 AMUnavailable

WindNE 13.2 ktonshoreTide5.5 ftrisingOffshore swellE 1.8 ft @ 6s

8 AMUnavailable

WindNE 14.1 ktonshoreTide7 ftrisingOffshore swellE 1.7 ft @ 6s

9 AMUnavailable

WindNE 15 ktonshoreTide8 ftrisingOffshore swellE 1.8 ft @ 6s

10 AMUnavailable

WindNE 16 ktonshoreTide8.5 ftfallingOffshore swellE 1.8 ft @ 6s

11 AMUnavailable

WindNE 16.2 ktcross-shoreTide7 ftfallingOffshore swellE 1.9 ft @ 6s

NoonUnavailable

WindNE 16.6 ktcross-shoreTide6 ftfallingOffshore swellE 2.0 ft @ 6s

1 PMUnavailable

WindNE 17.9 ktcross-shoreTide4.5 ftfallingOffshore swellE 2.2 ft @ 6s

2 PMUnavailable

WindNE 17.2 ktonshoreTide3.5 ftfallingOffshore swellE 2.3 ft @ 6s

3 PMUnavailable

WindNE 17.2 ktcross-shoreTide2.5 ftnear lowOffshore swellE 2.4 ft @ 6s

4 PMUnavailable

WindNE 17.2 ktcross-shoreTide2 ftrisingOffshore swellE 2.4 ft @ 6s

5 PMUnavailable

WindNE 16.6 ktonshoreTide3.5 ftrisingOffshore swellE 2.5 ft @ 6s

6 PMUnavailable

WindNE 15.7 ktonshoreTide4.5 ftrisingOffshore swellE 2.6 ft @ 6s

7 PMUnavailable

WindNE 14.8 ktonshoreTide6 ftrisingOffshore swellE 2.6 ft @ 6s

8 PMUnavailable

WindNE 14.3 ktonshoreTide7.5 ftrisingOffshore swellE 2.6 ft @ 6s

9 PMUnavailable

WindNE 14.2 ktonshoreTide8.5 ftrisingOffshore swellE 2.8 ft @ 6s

10 PMUnavailable

WindNE 14.2 ktonshoreTide9.5 ftfallingOffshore swellE 2.9 ft @ 6s

11 PMUnavailable

WindNE 14.4 ktonshoreTide8 ftfallingOffshore swellE 3.0 ft @ 6s

Tide

Boston station 8443970 · MLLW

Interpolated tide height Recommended window

About this spot

Model-grid forecast requested at the mapped coordinate; reef, headland, and nearshore transformations are unresolved. Beach break.

Mapped spot coordinate: 42.31, -70.88.

Mainland · Coast not verified · Ocean-facing bearing 90° · Location provenance

Model request point: Nantasket Beach (42.31, -70.88). Model output times describe valid conditions; the provider does not expose the model run issue time in this response.

Forecast sources

Data coverage 3/4 sources

Source availability is not forecast accuracy. Where an empirical model passes historical testing, its error and interval coverage are shown above. Source count cannot increase that confidence.

Coverage tier A · US_EAST · spot-level model point

Official breaking-surf report not connected for Massachusetts and Rhode IslandUnavailableUnavailable · Unavailable

US National Weather Service Surf Zone Forecast
No current NWS surf-zone period passed the explicit per-spot forecast-zone assignment.UnavailableNo source time
NOAA NDBC real-time station files
Current buoy observations are not forecasts for the selected future date.Not applicableNo source time
NOAA CO-OPS Tides and Currents API
Boston station 8443970; predicted high/low events above MLLW, converted to feet. Timestamp is retrieval time; provider issue time is not supplied.CurrentSep 22, 8:31 PM EDT
Open-Meteo Marine API
1 of 1 configured model points availableCurrentSep 22, 7:45 PM EDT
Open-Meteo Weather API
1 of 1 configured model points availableCurrentSep 22, 7:45 PM EDT
Surf-Forecast public pages
Spot discovery and break-specific HTML fallbackNot applicableNo source time
Surfline public spot pages
Break-specific comparison, cams, and metadataNot applicableNo source time

How best guesses are made

Best guesses combine usable wave and wind evidence, with qualitative confidence and specific limitations. A missing tide or local surf-height model does not prevent useful guidance. Tide levels use the named station datum; their effect at this break remains uncertain. Wind direction is relative to the mapped beach orientation, without calibrated terrain or shelter effects. The comparison is a heuristic, not a measured quality rating.