Upper Susa and Chisone Valleys

New snow and wind slabs above the tree line. A dangerous avalanche situation will persist in some cases.

New snow and wind slabs above the tree line. A dangerous avalanche situation will persist in some cases.

The large quantity of fresh snow as well as the sometimes deep wind slabs remain in some cases prone to triggering. The natural avalanche activity will decrease. Medium-sized and, in isolated cases, large natural avalanches are nontheless possible. In addition as the day progresses in particular at the base of rock walls, small and, in isolated cases, medium-sized moist and wet avalanches are possible. Even single winter sport participants can release avalanches in some places, including medium-sized ones. The avalanche prone locations are to be found adjacent to ridgelines and in gullies and bowls, and behind abrupt changes in the terrain. In particular on steep shady slopes the avalanches can be triggered in the old snow. Whumpfing sounds and the formation of shooting cracks when stepping on the snowpack are a clear indication of a weakly bonded snowpack. Remotely triggered avalanches are possible in isolated cases. Off-piste activities call for experience in the assessment of avalanche danger and caution.

Over a wide area 60 to 80 cm of snow, and even more in some localities, has fallen since Tuesday above approximately 2000 m. In the last few days easily released wind slabs formed at intermediate and high altitudes. The new snow of last week is bonding only slowly with the old snowpack. Large-grained weak layers exist in the old snowpack on shady slopes. Boxing Day: Artificially triggered avalanches and stability tests have confirmed a dangerous avalanche situation on very steep slopes.

The weather will be sunny. The weather conditions will facilitate a slight stabilisation of the snowpack.