Aemet vs Open-Meteo

AEMET OpenData is the official REST API of Spain's national meteorological agency, publishing forecasts, observations, climatology, and warnings ("avisos") restricted to Spanish territory. Requests return a metadata JSON envelope containing a signed URL that must be fetched separately to retrieve the actual payload (JSON, XML, or CSV depending on endpoint), and the service is documented via an interactive Swagger UI and machine-readable OpenAPI spec.

Open-Meteo is an open-source weather API that blends forecast and historical data from national weather services like NOAA, DWD, and Meteo-France, automatically selecting the highest-resolution model available for a given location. It requires no API key for non-commercial use and covers specialized domains including marine conditions, air quality, flood risk, and long-range climate projections.