Marine Weather & Wave Forecast Scraper

Hourly marine weather and wave forecasts for any coastal or offshore point on Earth — wave height, wave period, wave direction, swell, wind waves, sea surface temperature and ocean currents — plus a derived sea state label (Calm → High). No API key, no login, no proxy required.

Powered by the free Open-Meteo Marine API (ECMWF / MFWAM wave models).

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⚠️ Coastal coordinates only

The marine wave model runs on an ocean grid. Coordinates that fall on land return null for every variable. This Actor detects those rows, skips them, and logs a warning naming the offending location.

Input	Result
54.18,7.88,Helgoland	✅ 72 hourly rows
36.96,-122.02,Santa Cruz	✅ 72 hourly rows
-33.89,151.28,Bondi Beach	✅ 72 hourly rows
52.52,13.40,Berlin	❌ 0 rows — inland, no marine data

Rule of thumb: put your point on the water, or within a few kilometres of the shoreline. Deep bays, river mouths and lakes are frequently outside the model grid too. If a run returns nothing at all, the Actor fails loudly with a message listing the coordinates that produced no data.

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What you get

One dataset item per location × hour.

Field	Description
location_name	Your label, or "lat,lon" when no label was given
latitude, longitude	Model grid-cell centre actually used
timezone	Timezone of the returned timestamps (GMT)
time	ISO-8601 timestamp of the forecast hour
wave_height_m	Significant wave height, metres
wave_direction_deg	Mean wave direction, degrees
wave_period_s	Mean wave period, seconds
wind_wave_height_m	Wind-sea component height, metres
wind_wave_direction_deg	Wind-sea direction, degrees
wind_wave_period_s	Wind-sea period, seconds
swell_wave_height_m	Swell component height, metres
swell_wave_direction_deg	Swell direction, degrees
swell_wave_period_s	Swell period, seconds
sea_surface_temp_c	Sea surface temperature, °C
ocean_current_velocity_kmh	Surface current speed, km/h
ocean_current_direction_deg	Surface current direction, degrees
sea_state	Derived label — see table below
source	Always open-meteo-marine
scraped_at	UTC timestamp of the run

Sea state bands

Derived from wave_height_m using the WMO sea-state scale:

Wave height	sea_state
< 0.5 m	Calm
< 1.25 m	Smooth
< 2.5 m	Moderate
< 4 m	Rough
< 6 m	Very rough
≥ 6 m	High

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Input

Field	Type	Default	Notes
mode	select	forecast	Hourly marine forecast per location
locations	array	Helgoland + Santa Cruz	"lat,lon" or "lat,lon,Label" — coastal only
forecastDays	integer	3	1–7 days, 24 rows per day
maxItems	integer	1000	Hard cap across all locations, max 10000

{
  "mode": "forecast",
  "locations": [
    "54.18,7.88,Helgoland",
    "36.96,-122.02,Santa Cruz",
    "-33.89,151.28,Bondi Beach"
  ],
  "forecastDays": 3,
  "maxItems": 1000
}

Sample output

{
  "location_name": "Santa Cruz",
  "latitude": 36.958336,
  "longitude": -122.04166,
  "timezone": "GMT",
  "time": "2026-07-28T00:00:00+00:00",
  "wave_height_m": 1.26,
  "wave_direction_deg": 266.0,
  "wave_period_s": 9.95,
  "wind_wave_height_m": 0.58,
  "wind_wave_direction_deg": 302.0,
  "wind_wave_period_s": 4.1,
  "swell_wave_height_m": 0.72,
  "swell_wave_direction_deg": 251.0,
  "swell_wave_period_s": 12.4,
  "sea_surface_temp_c": 15.8,
  "ocean_current_velocity_kmh": 0.8,
  "ocean_current_direction_deg": 178.0,
  "sea_state": "Moderate",
  "source": "open-meteo-marine",
  "scraped_at": "2026-07-28T13:42:11.204871+00:00"
}

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Use cases

• Surf forecasts — combine swell_wave_height_m and swell_wave_period_s to rank break quality across a list of spots every morning.
• Sailing & yacht routing — pull wave_height_m, wave_direction_deg and ocean currents along a planned route and flag rough legs.
• Shipping & logistics — monitor sea state at ports and along shipping lanes to anticipate delays and heavy-weather routing.
• Offshore operations — wind farms, survey vessels and crew transfers need workability windows below a wave-height threshold; alert when sea_state crosses Rough.
• Aquaculture & coastal engineering — track sea surface temperature and wave loading at fixed sites over rolling forecast windows.

Pricing

Roughly $0.5 per 1,000 items. A three-day forecast for one location is 72 items, so ten coastal spots for three days costs about $0.36. Only pay for platform usage — the underlying data source is free and needs no key.

Tips

• One location + 7 days = 168 rows. Budget maxItems accordingly.
• Timestamps are returned in GMT/UTC — convert locally if you need local tide or daylight alignment.
• Run it on an Apify schedule (e.g. every 6 hours) to build a wave-history dataset for hindcasting or model comparison.
• Rows where the model has no data at all are dropped, so an empty dataset means every one of your coordinates was off-grid.

Related Actors

• Met.no Weather Scraper
• Weather Scraper
• NOAA Weather Alerts Scraper
• OpenSky Flights Scraper

Legal

Fetches publicly available forecast data from the Open-Meteo Marine API. No personal data is collected. Open-Meteo data is provided under CC BY 4.0 — attribute Open-Meteo when republishing.