Characteristics of extreme snowfall–wind-gust events in Finland (1960–2024): frequency, duration, and intensity
Compound weather events involving both strong wind gusts and intense snowfall can have significant impacts on critical infrastructure and public safety. This study analyses the frequency, duration, and intensity of such events in Finland using ERA5 reanalysis data for 1960–2024. Extreme wind gust and snowfall conditions were identified using spatially varying 95th and 98th percentile thresholds. Events with both snowfall and wind gust exceeding these thresholds simultaneously were classified as compound events (SWG). SWGs were most frequent along Finland's south facing coastal regions and eastern Finland. Increasing the threshold from 95th to 98th reduced the number of SWGs but emphasized the dominance of coastal areas and highlighted more severe cases. Approximately half of the events were short-lived (<5 h) and involved limited accumulation of snow water equivalent (<5 mm). However, a few prolonged SWGs were identified, characterized by wind gusts > 20 m s −1 , hourly snowfall rates > 2.5 mm h −1 , and total snowfall > 20 mm. Although rare, these extreme SWGs can create substantial operational challenges for energy production and other critical infrastructures. The results underscore the importance of incorporating compound-event analysis into hazard assessments and preparedness strategies for regions exposed to severe winter weather.
Authors
- Taru Olsson (ORCID: https://orcid.org/0000-0001-9703-4896)
- Terhi Kristiina Laurila (ORCID: https://orcid.org/0000-0002-0903-7331)
- Kirsti Jylhä (ORCID: https://orcid.org/0000-0003-0853-4747)
- Ari Aaltonen
Institutions
- Finnish Meteorological Institute (FI)
Publication Details
- Journal
- Natural hazards and earth system sciences
- Published
- 2026-09-29
- DOI
- https://doi.org/10.5194/nhess-26-4621-2026
- Primary Topic
- Meteorological Phenomena and Simulations
- Type
- article
- Field-Weighted Citation Impact
- 0.00