Sao Paulo State · Wednesday, Sep 23

Maresias

Updated Tue, Sep 22, 9:20 PM GMT-3

When to go

Around 5:00 PM

Large waves · Low confidence

8.1–8.1 ft · Offshore waves · not face height

Wind: 3.8 kt · cross-shore

Cautions

Large waves are forecast. Choose conditions that suit your experience.

Forecast details

Light wind should keep the water smoother.

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.

3:00 PM–5:00 PM · America/Sao_Paulo
Unfavorable wind · up to 7.1 kt · reported gusts up to 17.7 kt
Caution: This is the best available wind comparison, not a favorable-wind label. The selected wind is unfavorable for this break.
Offshore waves: 8.1–8.2 ft across the period. Surf height unavailable. Tide data unavailable.
Wind source time: Sep 22, 8:30 PM GMT-3. 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 6.8 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.
Tide unavailable: assessment incomplete, especially at shallow reef breaks.
A mapped coordinate does not establish nearshore grid resolution or terrain/shelter accuracy.

Wind SSE 7.3 kt

Tide Unavailable

Wave, wind and tide details

Offshore model swellS 5.6 ft @ 6sValid 2026-09-23 08:00 · America/Sao_PauloMarine grid -23.8750, -45.5417 · offshore model, not a local measurement

Offshore model sea6.6 ft @ 7.0sSignificant wave height including wind waves and swell; not breaking surfValid 2026-09-23 08:00 · America/Sao_Paulo

Model windSSE 7.3 ktonshoreValid 2026-09-23 08:00 · America/Sao_Paulo7.0 kt onshore component

TideUnavailableunavailableNo verified local tide station connected; no tide height estimated

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 Maresias
Time	Wind	Tide	Offshore swell
12 AM	SSE 8.5 ktonshore	Unavailableunavailable	ESE 1.9 ft @ 7s
1 AM	S 10.5 ktonshore	Unavailableunavailable	SE 2.8 ft @ 6s
2 AM	S 9.1 ktonshore	Unavailableunavailable	SSE 3.7 ft @ 5s
3 AM	S 10.1 ktonshore	Unavailableunavailable	S 4.6 ft @ 5s
4 AM	S 7.3 ktonshore	Unavailableunavailable	S 4.4 ft @ 5s
5 AM	S 6.3 ktonshore	Unavailableunavailable	SSW 4.3 ft @ 6s
6 AM	SSE 8.2 ktonshore	Unavailableunavailable	SSW 4.1 ft @ 6s
7 AM	SSE 8.5 ktonshore	Unavailableunavailable	SSW 4.9 ft @ 6s
8 AM	SSE 7.3 ktonshore	Unavailableunavailable	S 5.6 ft @ 6s
9 AM	SSE 8.2 ktonshore	Unavailableunavailable	S 6.4 ft @ 6s
10 AM	SSE 7.7 ktonshore	Unavailableunavailable	S 6.6 ft @ 7s
11 AM	SSE 6.8 ktonshore	Unavailableunavailable	S 7.0 ft @ 7s
Noon	SE 7.4 ktonshore	Unavailableunavailable	S 7.2 ft @ 7s
1 PM	SSE 8.1 ktonshore	Unavailableunavailable	S 7.4 ft @ 7s
2 PM	SSE 8 ktonshore	Unavailableunavailable	S 7.7 ft @ 7s
3 PM	SSE 7.1 ktonshore	Unavailableunavailable	S 7.9 ft @ 7s
4 PM	SE 5.1 ktonshore	Unavailableunavailable	S 7.8 ft @ 7s
5 PM	SE 3.8 ktcross-shore	Unavailableunavailable	S 7.7 ft @ 8s
6 PM	SE 5.1 ktcross-shore	Unavailableunavailable	S 7.7 ft @ 8s
7 PM	SE 5.3 ktcross-shore	Unavailableunavailable	S 7.6 ft @ 8s
8 PM	SE 6.1 ktcross-shore	Unavailableunavailable	S 7.5 ft @ 8s
9 PM	ESE 4.7 ktcross-shore	Unavailableunavailable	S 7.4 ft @ 7s
10 PM	E 3 ktcross-shore	Unavailableunavailable	S 7.2 ft @ 7s
11 PM	NE 2.4 ktcross-shore	Unavailableunavailable	S 7.0 ft @ 8s

12 AMUnavailable

WindSSE 8.5 ktonshoreTideUnavailableunavailableOffshore swellESE 1.9 ft @ 7s

1 AMUnavailable

WindS 10.5 ktonshoreTideUnavailableunavailableOffshore swellSE 2.8 ft @ 6s

2 AMUnavailable

WindS 9.1 ktonshoreTideUnavailableunavailableOffshore swellSSE 3.7 ft @ 5s

3 AMUnavailable

WindS 10.1 ktonshoreTideUnavailableunavailableOffshore swellS 4.6 ft @ 5s

4 AMUnavailable

WindS 7.3 ktonshoreTideUnavailableunavailableOffshore swellS 4.4 ft @ 5s

5 AMUnavailable

WindS 6.3 ktonshoreTideUnavailableunavailableOffshore swellSSW 4.3 ft @ 6s

6 AMUnavailable

WindSSE 8.2 ktonshoreTideUnavailableunavailableOffshore swellSSW 4.1 ft @ 6s

7 AMUnavailable

WindSSE 8.5 ktonshoreTideUnavailableunavailableOffshore swellSSW 4.9 ft @ 6s

8 AMUnavailable

WindSSE 7.3 ktonshoreTideUnavailableunavailableOffshore swellS 5.6 ft @ 6s

9 AMUnavailable

WindSSE 8.2 ktonshoreTideUnavailableunavailableOffshore swellS 6.4 ft @ 6s

10 AMUnavailable

WindSSE 7.7 ktonshoreTideUnavailableunavailableOffshore swellS 6.6 ft @ 7s

11 AMUnavailable

WindSSE 6.8 ktonshoreTideUnavailableunavailableOffshore swellS 7.0 ft @ 7s

NoonUnavailable

WindSE 7.4 ktonshoreTideUnavailableunavailableOffshore swellS 7.2 ft @ 7s

1 PMUnavailable

WindSSE 8.1 ktonshoreTideUnavailableunavailableOffshore swellS 7.4 ft @ 7s

2 PMUnavailable

WindSSE 8 ktonshoreTideUnavailableunavailableOffshore swellS 7.7 ft @ 7s

3 PMUnavailable

WindSSE 7.1 ktonshoreTideUnavailableunavailableOffshore swellS 7.9 ft @ 7s

4 PMUnavailable

WindSE 5.1 ktonshoreTideUnavailableunavailableOffshore swellS 7.8 ft @ 7s

5 PMUnavailable

WindSE 3.8 ktcross-shoreTideUnavailableunavailableOffshore swellS 7.7 ft @ 8s

6 PMUnavailable

WindSE 5.1 ktcross-shoreTideUnavailableunavailableOffshore swellS 7.7 ft @ 8s

7 PMUnavailable

WindSE 5.3 ktcross-shoreTideUnavailableunavailableOffshore swellS 7.6 ft @ 8s

8 PMUnavailable

WindSE 6.1 ktcross-shoreTideUnavailableunavailableOffshore swellS 7.5 ft @ 8s

9 PMUnavailable

WindESE 4.7 ktcross-shoreTideUnavailableunavailableOffshore swellS 7.4 ft @ 7s

10 PMUnavailable

WindE 3 ktcross-shoreTideUnavailableunavailableOffshore swellS 7.2 ft @ 7s

11 PMUnavailable

WindNE 2.4 ktcross-shoreTideUnavailableunavailableOffshore swellS 7.0 ft @ 8s

Tide

Local tide station unavailable

Tide predictions are unavailable for this period.

About this spot

Model-grid forecast requested at the mapped coordinate; reef, headland, and nearshore transformations are unresolved. Beach break. Named-break page reports an exposed beach with south swell and north offshore wind; orientation reviewed at 180 degrees.

Mapped spot coordinate: -23.8137, -45.539.

Mainland South America · São Sebastião mainland south-facing exposed Atlantic beach coast · Ocean-facing bearing 180° · Location provenance

Model request point: Maresias (-23.8137, -45.539). Model output times describe valid conditions; the provider does not expose the model run issue time in this response.

Forecast sources

Data coverage 2/6 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 C · BRAZIL · spot-level model point

Brazilian Navy Marine Forecasts
Brazilian Navy CHM publishes official 24/48-hour marine bulletins, but the checked public response returned a managed Cloudflare challenge. No timestamped forecast-area payload is scraped or relabeled as breaking surf.UnavailableNo source time
Brazilian Navy PNBOIA / CHM
The checked PNBOIA public page returned a managed Cloudflare challenge; no spot-assigned current observation is connected.UnavailableNo source time
WorldTides API
WorldTides returned HTTP 400 API key invalid without a credential; no station identity, distance, datum, timezone, or prediction is available.UnavailableNo source time
Open-Meteo Marine API
1 of 1 configured model points availableCurrentSep 22, 8:30 PM GMT-3
Open-Meteo Weather API
1 of 1 configured model points availableCurrentSep 22, 8:30 PM GMT-3
Copernicus Marine Global Ocean Waves
Copernicus Marine requires an account/toolbox workflow and no independently connected response is available.UnavailableNo source time
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.