EU Science Hub

Typical Meteorological Year

A typical meteorological year (TMY) is a set of meteorological data with data values for every hour in a year for a given geographical location. The data are selected from hourly data in a longer time period (normally 10 years or more). For each month in the year the data have been selected from the year that was considered most 'typical' for that month. For instance, January might be from 2007, February from 2012 and so on.The solar radiation data used for the TMY have been calculated from satellite data by the CM SAF collaboration ( All other data have been taken from the ECMWF ERA-interim reanalysis ( Air temperature data have been corrected for elevation. The selection of the months for the TMY is done using the method described in the international Standard ISO 15927-4. The selection is done based on air temperature, global horizontal irradiance and relative humidity.