The 2024/2025 winter season in the Northern French Alps has proven to be particularly deadly, with 18 fatalities reported so far, 15 in the Northern Alps. A significant factor contributing to these tragic losses has been the persistent weak layer in the snow-pack in the interior mountain ranges. This layer was due to low snow depths at the start of the season, and continues to pose a considerable risk to backcountry skiers and snowboarders.
An unstable Snow-Pack
Recent weather conditions have made the snow-pack in the region particularly prone to avalanches. A complex mix of fresh snow, strong winds, and fluctuations in temperature has created a volatile snow structure. Stéphane Bornet, director of the National Association for the Study of Snow and Avalanches (ANENA), explains that the snow-pack has undergone multiple layers of accumulation, particularly at higher altitudes and along ridgelines where the wind tends to transport snow and form dangerous snow slabs.
This week's avalanches, which claimed the lives of three individuals in Savoie, were a stark reminder of the ongoing dangers. The headline avalanche risk rating was of 3 out of 5 (a "considerable risk") but experts warn that this level of danger is often underestimated by those venturing into the backcountry. According to Ludovic Saint-Bonnet, head of the CRS des Alpes mountain rescue, skiers often perceive a level 3 risk as moderate, which leads to a false sense of security. In fact, this level is one of the most dangerous, as the conditions are subtle, and the risks harder to predict. 10 of the 12 fatal incidents this season were at risk 3. In fact, discounting risk 5 which really only applies to infrastructure it is in the upper half of the risk matrix. One of the avalanched groups had found the conditions on the ground last Saturday more dangerous than they anticipated, an important point in avalanche risk evaluation. As the Munter 3x3 method teaches, you need to continually evaluate your choices based on regional, local and zonal information.
A deadly winter in the French Northern Alps
There is considerable variation in the number of avalanche fatalities from one season to another. The biggest variable is weather. The last two winters have seen stable conditions and fewer fatal incidents. This may have led backcountry travelers into a false sense of security. As avalanche expert Alain Duclos explains "2023-2024 began with heavy precipitation and lots of snow, creating a thick, solid snow-pack right from the start of the season. In 2024-2025, the opposite is true with light precipitation interspersed with cold, sunny weather, creating a rather thin and consequently very fragile snowpack. And it's on this fragile structure that we have accumulations that turn out to be very unstable, either because of snow or wind transport. Between last year and this year, we have two completely different snow-packs, and therefore very different accident records. Last year in the Savoie, we had zero fatalities, but this year we have a lot."
Avalanche Fatalities and Safety Measures
The fatalities that have occurred throughout the 2024/2025 season highlight a number of issues, especially when individuals venture off-piste without proper equipment, knowledge or alone. In the Savoie alone, 12 people have died. Across the season, incidents have ranged from solo skiers caught in avalanches, to larger groups triggering large slides while skiing or touring in unstable areas.
Alain Duclos warns to "avoid slopes over 30 degrees and where there is variable cover, if there's a lot of snow on a slope when there's none elsewhere, take care! Where there are bumps that are stripped by the wind, where there are rocks and grass that is visible then on the slope right next to it, it's all white. That's snow piled up by the wind, and that's where it's dangerous.”
Another key to reducing these risks lies in preparation. Skiers are reminded of the critical importance of safety equipment, including avalanche transceivers, probes, and shovels. The use of an airbag backpack, while not essential, can further increase survival chances. However, safety gear is only effective if users know how to operate it. Regular practice with companions is vital to ensuring readiness in the event of an emergency.
Beyond equipment, experts emphasize the importance of route planning and being willing to cancel or alter a planned trip based on conditions. As Stéphane Bornet states, knowing when to turn back is a sign of maturity and prudence in mountain safety.
Duclos also emphasises the need for anticipation. Slabs can only be only be triggered on slopes inclined at more than 30 degrees. “In France today, we're very lucky to have easy access to maps showing slopes of over 30 degrees. So today, if I go ski touring in the mountains and the weather's really nice, I don't go on slopes over 30 degrees, especially if they've been loaded by the wind.”
Weather Trends and the Impact of Climate Change
The avalanche risk may be exacerbated by changing weather patterns, particularly those associated with climate change. Recent weeks have seen a significant shift in snow conditions, with fresh snow followed by hard wind-blown slabs, creating the ideal conditions for avalanches. Although the avalanche risk has decreased this week, it remains present in certain areas, particularly around Mont Blanc and parts of the Savoie.
Nicolas Roux, an expert from Météo France, explained that these snow slabs can stabilize quickly, but only for a few days, making it essential for backcountry travelers to stay informed about changing conditions. The increasing intensity and frequency of snowstorms in the Alps, linked to climate change, are expected to continue, leading to more unstable snow conditions in the future.
Vigilance and Preparation
The tragic fatalities that have marked this winter season are a sobering reminder of the dangers that exist in the mountains, especially in the backcountry. As Météo France forecasts, the upcoming days will bring warmer temperatures and more sunshine, likely drawing more people into the mountains. However, those venturing into the wild must remain vigilant, prepare thoroughly, and prioritize safety at all times.
In light of these tragedies, it is more crucial than ever for mountain enthusiasts to respect the avalanche warnings, carry the right equipment, and, most importantly, understand that the mountains can be unpredictable and when in doubt, turn back.
Further Information
Updated digital maps aim to improve safety for backcountry enthusiasts