The increasing development of mountainous areas and the growth of tourism and economic activities have led to a rise in the number of facilities exposed to natural hazards. Climate change is altering the activity of hazardous natural processes in mountainous regions. Atmospheric precipitation plays a key role in triggering hydrological hazards in complex terrains. This study addresses the detection of statistically significant changes in precipitation patterns at the regional level and their correlation with the annual cycle of hazardous hydrometeorological processes that threaten infrastructure and populations in the Eastern Caucasus. Historical data from meteorological stations located in the mountainous zones of the Republic of Dagestan and the Chechen Republic were used as primary sources. Time series of various precipitation characteristics (annual, seasonal, monthly, and daily) were compiled, covering the period of most intense warming from 1976 to 2023. Mathematical statistics and big data processing methods were applied to identify statistically significant trends in atmospheric precipitation. The results indicate that common regional trends in precipitation patterns across the Eastern Caucasus include an increase in various precipitation characteristics in March and a decrease in August. Comparing these trends with the annual distribution of hazardous hydrometeorological events suggests that the mountainous part of the region will likely continue to experience a decline in precipitation characteristics during the high flood and mudflow season. At the same time, high-altitude areas may see an increase in rainfall-induced hydrological hazards in July, linked to the observed trend of more frequent high-intensity precipitation days.