Marine Swell Forecast
marine.ocean.swellForecast hourly swell height, direction, and period at an ocean coordinate for up to 16 days to support surf, sailing, and aquaculture planning.
Instructions
Hourly swell forecast at an ocean coordinate — swell wave height (m), swell direction (°), and swell period (s) for up to 16 days. Swell consists of wind-generated waves that have propagated far from their origin, typically with longer periods (>10s) and more regular patterns than wind-sea. High-period swell (>12s) is ideal for surfing; low-period swell (<6s) indicates local chop. Swell direction indicates where the swell is coming from (degrees clockwise from north). Useful for surf forecasting, sailing passage planning, and aquaculture site assessment. Source: Open-Meteo Marine API, CC BY 4.0, no authentication required.
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| latitude | Yes | Latitude of the ocean location in decimal degrees (e.g. 51.5 for English Channel, 48.5 for Bay of Biscay). Must be over open water — land coordinates return null values. | |
| timezone | No | Timezone for the returned time values (e.g. "UTC", "Europe/London", "America/New_York"). Defaults to UTC. | |
| longitude | Yes | Longitude of the ocean location in decimal degrees (e.g. -14.0 for Atlantic, 2.3 for North Sea). | |
| forecast_days | No | Number of days to forecast (1–16). Defaults to 7. Hourly data is returned for each day. |
Output Schema
| Name | Required | Description | Default |
|---|---|---|---|
| error | No | Present only when the call failed. Includes error code, message, request_id, and any provider-specific extras. | |
| result | No | Tool response payload. Shape varies per tool — consult the tool description and inputSchema. May be an object, array, string, or number depending on the upstream provider response. |