Middle Lys Valley

Slab avalanches are the main danger. Moist and wet avalanches are possible from the morning.

Slab avalanches are the main danger. Moist and wet avalanches are possible from the morning.

As a consequence of the strong to storm force northerly foehn wind, fresh snow drift accumulations formed during the last few days. In the course of the day the wind slabs will increase in size additionally. Caution is to be exercised on very steep slopes, and in gullies and bowls, and behind abrupt changes in the terrain. Avalanches can be released, even by a single winter sport participant. Weak layers in the old snowpack necessitate caution. In some places the avalanches can be triggered in the old snow and reach quite a large size. Remotely triggered avalanches are possible. Whumpfing sounds and the formation of shooting cracks when stepping on the snowpack serve as an alarm sign. With the freezing level at 2600 metres combined with the foehn wind and solar radiation, wet and moist avalanches are expected from the morning onwards, including large ones in isolated areas.

Over a wide area 20 to 50 cm of snow has fallen since Sunday above approximately 1600 m. Until Saturday the wind will be strong. Adjacent to ridgelines and in pass areas snow depths vary greatly, depending on the infuence of the wind. The snowpack is unfavourably layered. Faceted weak layers exist in the old snowpack in particular on west, north and east facing slopes. Some medium-sized to large natural dry avalanches have been released in the last few days.

The danger of moist and wet avalanches will increase during the day.