Climatology of thunderstorms in the Baltic countries, 1951-2000.

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. [ABSTRACT FROM AUTHOR]