Weersdata

Weersdata refers to the set of weather-related observations and derived products collected, stored, and distributed for analysis, forecasting, and climate research. It includes raw observations, model outputs, and reanalysis data. Observational data come from weather stations, buoys, radiosondes, weather radar, and satellites, recording variables such as temperature, precipitation, humidity, wind speed and direction, air pressure, cloud cover, solar radiation, and visibility. Model data are produced by numerical weather prediction systems and provide gridded forecasts and ensemble data. Reanalysis blends observations with models to produce consistent historical climate fields.

Data sources include national meteorological services (for example KNMI in the Netherlands), regional weather networks, space agencies, and oceanographic organizations. Formats and standards commonly used are netCDF, GRIB, and BUFR; metadata typically includes time, location (latitude and longitude), altitude, instrument, and units. Standards are coordinated by international bodies such as the World Meteorological Organization.

Access and usage vary by provider, but many weather data are open data or accessible via APIs and portals. Users include meteorologists, researchers, planners, and businesses in sectors such as agriculture, aviation, transport, and disaster management. Data quality is supported by quality control, homogenization, and calibration efforts; data assimilation and verification underpin forecasting and climate analysis.

History tracks the expansion from manual observations to automated networks, with global coordination by the WMO and increasing emphasis on open data distribution in recent decades.