Climatology of thunderstorms in the Baltic countries, 1951–2000

Abstract

This paper provides an overview of the thunderstorm climate of the Baltic countries during the period of 1951–2000. Our study area is in northeastern Europe and encompasses Estonia, Latvia, and Lithuania. Visual thunderstorm observations at 59 weather stations were used as a data source. The mean annual number of thunderstorm days was 12–29.5. The seasonal cycle of thunderstorm hours with a daily step unexpectedly showed two maxima, whereas the monthly numbers of thunderstorm days had one clear mid-latitude specific peak between June and August. The diurnal cycle of thunderstorm hours showed a peak between 1400 and 1800 local time and a minimum between 0400 and 1000 hours local time. The average annual duration of thunderstorm events was 112 min. The average number of thunderstorm events per thunderstorm day was around 1.1–1.2. Our results showed that the thunderstorm climate of the Baltic countries generally resembles that of other mid-latitude study sites.