70+ years of global, hourly historical and forecast weather data from NOAA and ECMWF.
Oikolab API is a free Weather API that requires apiKey authentication, is served over HTTPS and supports CORS, so it can be called from the browser.
Access historical and forecast weather data with the Oikolab Weather API. Query global climate datasets, forecasts, and weather parameters.
Details from docs.oikolab.com.

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Geocode an address, validate an email, track a flight or pull stock data with one account, one dashboard and one API key.
US coastal tides, water levels, currents and meteorological observations
Data from Personal Weather Stations called senseBoxes
The Oikolab API is provided by Oikolab (docs.oikolab.com). Access historical and forecast weather data with the Oikolab Weather API. Query global climate datasets, forecasts, and weather parameters.
Yes. The Oikolab API is listed in the Weather category of the public-apis directory, which only includes APIs that are free or have a free tier. Check its documentation for rate limits and paid plans.
Yes. The Oikolab API uses apiKey authentication, so you need to register for credentials before making requests.
Yes. The Oikolab API supports CORS, so front-end JavaScript can call it directly.
Yes. The Oikolab API is served over HTTPS, so it's safe to use in production.