A new Swiss snowfall record has been set at the Bortelsee station in the Simplon region of Switzerland, where 89 inches (226 centimeters) of snow fell within just two days, and 97 inches (247 centimeters) accumulated over three days. This unprecedented event, recorded from April 15 to 17, 2025, now stands as the largest amount of snow ever measured in short timeframes in Switzerland, surpassing the previous records of 85 inches (215 centimeters) in two days at the Bernina Pass in April 1999 and 90 inches (229 centimeters) in three days at Weissfluhjoch in February 1990.
The snowfall was primarily driven by the “Hans” depression, a low-pressure system that developed over the Gulf of Genoa. Named by Italian meteorological services, Hans channeled a strong southeasterly flow from the Mediterranean, carrying warm, moisture-laden air into the southern Alps. As this air mass encountered the mountainous terrain, it was forced upward, resulting in intense orographic precipitation on the southern slopes, particularly in the Simplon region. The interaction between this moist air and colder air masses at higher elevations led to significant snowfall, culminating in the record-breaking accumulations observed at Bortelsee.
- Related: Avalanches in Val Thorens, France, Leave One Critically Injured and Force Ski Area Shutdown
The impact of this weather system extended beyond snowfall records. Heavy snow forced the closure of several major ski resorts, including Zermatt in Switzerland and Val d’Isere in France, due to heightened avalanche danger. Rail and road access to these resorts was temporarily cut off, and power outages affected parts of upper Valais. Authorities issued avalanche warnings and weather alerts as the risk of avalanches, floods, and landslides increased across the Alps.
