The deadliest sudden weather-related events in the Czech Lands, 1851–2025 CE

Abstract. Extreme weather-related events can be accompanied not only by extensive material damage, but also by many fatalities. The question is: what is the long-term context of the deadliest weather events with respect to the increasing severity and frequency of weather extremes accompanying recent climate change? This paper presents the sudden weather-related events with the highest numbers of fatalities (≥20) over the territory of the Czech Lands (now the Czech Republic) in the 1851–2025 CE period, which were connected to or influenced by floods, windstorms, convective storms, thunderstorms, snow, and fog. For each of the 13 selected events, meteorological conditions, their course, accompanying circumstances, and selected fatality characteristics such as sex and age are described in detail. Six events occurred in the second half of the 19th century, three in the first half of the 20th century, four in its second half, and none after 2000. Although floods were the most frequent cause of high fatality numbers in six cases, two train and two airplane accidents connected with snow and fog also appeared among the deadliest events selected. The flash flood in western Bohemia from 25–26 May 1872, claiming 244 lives, was the most tragic documented event over the Czech territory since 1851 CE. Only the flood event in Moravia and Silesia in July 1997, with 58 fatalities, occurred during the period of recent climate change characterized by the highest temperature increase since the 1980s. The results show that the effects of long-term changes in the environmental, socioeconomic, and societal situation in the country, directed toward more effective risk management and rescue activities, aimed at increased saving lives in extreme weather events during past 175 years, including recent climate change. The detail description of the historical investigation allows future replication of such research in other countries.