Europe's Deadliest Ski Season: Avalanches Claim 86 Lives Amid Unusual Weather
This winter has been labelled Europe's deadliest ski season on record, with avalanches causing 86 fatalities in the first two months of the year alone. In the Italian Alps, a tragic week saw 13 climbers, hikers, skiers, and snowboarders lose their lives—the highest weekly toll ever recorded. Meanwhile, in France, the popular Valloire area has witnessed 28 deaths this winter, including two British skiers.
Why Are Avalanches So Prevalent This Year?
According to scientific experts, a combination of specific weather patterns and the growing popularity of off-piste skiing is responsible for the increase in deadly snowslides. Frederic Jarry, project manager at the French National Association for the Study of Snow and Avalanches, stated to the Daily Mail: 'This is a winter unlike any we've experienced in the past few years.'
Skiers are encountering snow with a soft, crumbly layer trapped beneath a heavy slab, known as a 'persistent weak layer'. This fragile crust supports an entire winter's accumulation of snow, meaning even the slightest disturbance from an off-piste skier can trigger a massive wall of snow and ice cascading down the mountain.
The Scale and Speed of Avalanches
Fully developed avalanches can contain up to one million tonnes of snow, ice, and debris, travelling at speeds of 200mph (320 km/h), making them the deadliest threat in mountainous regions. This year, fatalities have occurred across the Alps, Pyrenees, and Carpathian Mountains, with deaths reported in France, Italy, Austria, Switzerland, Spain, Slovenia, Slovakia, and even Lake Tahoe in the Sierra Nevada Mountains.
The European Avalanche Warning Services, which monitors avalanche fatalities, notes an average of 100 deaths per year in Europe. However, in the first six weeks of 2026 alone, avalanches claimed 77 lives, with the total now at 86. France leads with 25 deaths, followed by Italy with 21, Austria with 14, Switzerland with nine, and Spain with eight.
Understanding Snow Layers and Avalanche Triggers
When observing a blanket of white snow, it is easy to perceive it as a uniform block. In reality, snow at ski resorts consists of distinct layers deposited throughout the winter. An avalanche occurs when one layer slides over others, forming an unstoppable river of snow.
Light snowfall and cold weather early in the winter created a fragile crust, or persistent weak layer, now covered by a thick slab of snow. This weak layer has developed across European mountain ranges, contributing to deaths in multiple countries. On slopes of 30° or more with this dangerous slab structure, avalanches pose a constant threat.
Weather Conditions Exacerbating Risks
This year, weather conditions have maximised slope danger. Mr Jarry explained: 'The high number of fatal accidents and deaths is specifically due to the season's unique snow and weather conditions.' The winter began with fine, dry weather depositing a light snow coat, followed by a cold snap that transformed small, densely packed snow crystals into large hollow grains that slide rather than stick together.
Dr Jürg Schweizer of the WSL Institute for Snow and Avalanche Research SLF told the Daily Mail: 'The shallow snowpack transformed into weak layers consisting of poorly bonded crystals, a pile of rubble, also called sugary snow.' In mid-January, the first significant snowfall covered these weak basal layers, creating the perfect slab-on-weak-layer combination for dry-snow slab avalanches, the deadliest type for skiers.
The Role of Off-Piste Skiing
The persistent weak layer does not dissipate; it remains beneath new snow, awaiting a trigger. While natural causes often initiate collapses, human-triggered avalanches are the most dangerous. Skiing, snowboarding, hiking, or climbing through unstable snowpack generates vibrations that can dislodge the precariously balanced slab.
Dr Nicolas Eckert, a mountain risk expert from Grenoble Alpes University, said: 'Avalanche risk in the European Alps is nowadays mostly for mountain practitioners that trigger avalanches themselves.' Off-piste skiing, which involves leaving designated resort areas for quieter routes, has surged in popularity since the pandemic, with a 13% increase in participation between 2022 and 2023. This activity carries heightened avalanche risks, especially with a persistent weak layer present.
Recent Tragedies and Trends
Recent incidents highlight the dangers. Last Sunday, an off-trail avalanche killed two skiers and injured another on the Italian side of the Mont Blanc Massif. On Monday, British skiers Stuart Leslie, 46, and Shaun Overy, 51, died in an avalanche while skiing off-piste under supervision in Val d’Isère, France. On Tuesday, an avalanche near La Gave killed two of five skiers, including a Polish-born British man.
Dr Eckert noted: 'Risk change is mainly governed by change in the number of off-track skiers and their ability to cope with risk. The number of off-track skiers is increasing, which should directly increase overall risk.' Despite a general trend toward safer off-piste skiing over the past decade, thanks to better warnings, safety equipment, and stable conditions, this year's unique weather has heightened risks for even well-prepared skiers.
Climate Change and Future Avalanche Risks
Looking ahead, scientists are examining how climate change will impact avalanche trends. Most expect a reduction in total avalanches annually due to less snow from warming climates. A recent pre-print study found a 6% decrease per decade in avalanche numbers between 1958 and 2023, with predictions of 30% fewer by 2100 compared to 1990. However, at altitudes above 3,000 metres, avalanches may become more frequent due to extreme weather.
Dr François Doussot, an avalanche expert for Meteo France, distinguishes between 'avalanche hazard' and 'avalanche risk'. While hazard (likelihood of occurrence) may decrease, risk is increasing due to greater exposure. He stated: 'The risk is highly dependent on the exposure, which is certainly changing faster than the hazard.' As snow recedes from lower altitudes, skiers will seek higher, more dangerous slopes where avalanches are becoming more common.
Future avalanches may contain wetter, heavier snow, increasing lethality. One study concluded: 'Higher snow densities in avalanche debris will likely interfere with the respiration of completely buried victims. Asphyxia and trauma, as causes of avalanche death, may increase.' Additionally, thinner, persistent weak layers could become more frequent, further endangering off-piste skiers.
Mr Jarry emphasised: 'The mountain, the snow and weather conditions are constantly evolving. It's up to the participants to adapt their approach and know when to change their plans, abandoning certain routes to choose more suitable and interesting ones.'
