Upper Susa and Chisone Valleys

Weak layers in the old snowpack represent the main danger.

Weak layers in the old snowpack represent the main danger.

Avalanches can be released in the weakly bonded old snow by people. Caution is to be exercised in particular adjacent to ridgelines above the tree line, as well as at transitions from a shallow to a deep snowpack, when entering gullies and bowls for example. Whumpfing sounds and the formation of shooting cracks when stepping on the snowpack are a clear indication of a weakly bonded snowpack. Weak layers in the old snowpack are treacherous. The wind slabs are easy to recognise but can be released in isolated cases at their margins. As a consequence of warming during the day and solar radiation moist avalanches are possible below approximately 2500 m. This applies in particular on very steep sunny slopes.

The meteorological conditions will cause a gradual settling of the near-surface layers in particular at low and intermediate altitudes. Precarious weak layers exist in the snowpack in particular on shady slopes. Artificially triggered avalanches and reports filed by observers confirm the existence of a weak snowack. As a consequence of rising temperatures and solar radiation a crust formed on the surface during the last few days. This applies in particular on sunny slopes.