Avalanches swept away more people than usual in the winter of 2025–26, though the death toll remained broadly in line with the average.
A fragile snowpack led to a surge in incidents. By the end of March, 244 people had been caught in 171 avalanches, according to the WSL Institute for Snow and Avalanche Research SLF. Over the past decade the averages were 182 people in 127 incidents. Yet fatalities, at 15, were typical. Thirty-seven people were completely buried. In most of the 13 fatal accidents, avalanches were triggered in weak layers of old snow.
Avalanches involving people were recorded almost daily between January 10th and February 22nd. A final tally will be available only at the end of the hydrological year on September 30th, the institute notes.
The underlying problem was instability. After an early start to winter in late November and early December, dry and sunny weather persisted into January, leaving little snow cover at the turn of the year. Large temperature differences transformed the snowpack, creating weak layers prone to collapse. Such conditions are hard to detect in the field, even for experts, and avalanches released deep in the snowpack tend to be large and dangerous.
The risk peaked in midwinter. From mid-January to mid-February, light but frequent snowfall covered the fragile base, raising the danger across the Alps. The worst-affected regions were Valais, Ticino and Graubünden. Heavy snowfall in mid-February—up to 150cm in parts of Lower Valais—pushed the danger level to the maximum (level 5) on February 17th. A further metre of snow fell in the north between February 18th and 22nd.
Conditions eased in early March before deteriorating again later in the month, particularly on the southern side of the Alps. Many avalanches were subsequently triggered by people, especially in Valais and Graubünden, though none proved fatal. Fresh snowfall in the north at the end of March briefly raised the danger once more.
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