Meteorological data can be generated with Meteonorm using a database with long term monthly average measurement data from different stations. In the recent software versions there are more than 7000 meteorological stations worldwide available. If no meteorological station is available in the database for a desired site, meteorological data will be interpolated based on the data of the nearest stations. The accuracy of the generated data depends on the accuracy of measurements of used stations in the database, the distance to the next stations and the interpolation method.

A density of weather stations in the program database is relatively low for Central Asia compared to Europe. In total, about 100 stations are available in the program database (5.1 and 6.0) for Central Asia with data for ambient temperature, humidity, velocity and wind direction, precipitation and only 3 stations with solar radiation data. The mentioned station Frunze in Bishkek is available in the program database, but without solar radiation data. The nearest database station to Bishkek with solar radiation data is about 600 km away in Tashkent, Uzbekistan. Unlike previous versions, Meteonorm 6.0 uses satellite-derived solar radiation data additionally to the weather stations for interpolation of solar radiation.

Bishkek city is already defined in Meteonorm 5.1 and 6.0 but with a wrong altitude of 2111 m instead of 760 m. This leads to significantly lower ambient temperatures compared to the measure

values at the weather station Frunze (Fig 1). Because of the wrong altitude, ambient temperature for Bishkek was obviously interpolated by Meteonorm using data from a station Naryn (about 300 km away) with a similar altitude of 2041 m. Thus, it is necessary for further investigations to define Bishkek in Meteonorm manually as a new site with the correct coordinates.