The State of the Swiss Snowpack: Deep Totals & Unstable Layers - SnowBrains

"Last week alone, parts of western Switzerland were buried under 1 to 1.5 meters (3 to 5 feet) of snow. Another meter fell this week in some regions, pushing fresh storm totals to as much as 2.5 meters (8 feet). The new snow has helped erase what had been a snow-poor winter in the west, with snow depths in some areas now well above seasonal averages."

"But the snow came with a serious catch. What makes this cycle particularly concerning is what lies beneath the new snow. The fresh load fell on an older, unstable snowpack that in many regions contained angular, faceted weak layers. North of a Rhône-Rhine line, these weak layers were present but less pronounced. South of that line, however, the base of the snowpack was in places entirely faceted and structurally weak."

"The weight of up to 2.5 meters of new snow dramatically increased stress on these fragile layers. Forecasters warned that spontaneous avalanches were likely, and many of them have fractured deep into the snowpack. In southern regions, where weak layers were especially pronounced and only thinly covered before the storms, even slightly smaller additional loads were expected to trigger natural releases."

Switzerland received intense snowfall over two weeks, with western areas accumulating up to 2.5 meters and some regions now above seasonal averages. The fresh storms erased earlier snow deficits in parts of the west. The new snow fell onto older snowpacks containing angular, faceted weak layers, especially pronounced south of a Rhône–Rhine line. The added weight increased stress on fragile layers, triggering spontaneous avalanches and deep fractures into the snowpack. Audible settling noises indicated persistent slab instability, and avalanches were reported as easy to trigger, including remote releases. Snow depths remain variable across the country.

Read at SnowBrains