Cracks in snow propagate faster than expected

Since 10 January 2026, the WSL Institute for Snow and Avalanche Research (SLF) has received reports of hundreds of "whumpfs" (i.e., sounds indicating a collapse in the snowpack) and of remote triggering events—unmistakable signs of a critical avalanche situation involving a weak snowpack. A whumpf is where snow sports enthusiasts cause a fracture in a weak layer of the snow, which within seconds propagates as a crack across the terrain. If the crack reaches steep terrain, this may trigger an avalanche—a remote triggering event.