Middle Lys Valley

The sometimes strong wind will transport the new snow. Weak layers in the old snowpack are treacherous.

The sometimes strong wind will transport the new snow. Weak layers in the old snowpack are treacherous.

5 to 20 cm of snow will fall above approximately 2400 m. As a consequence of new snow and strong wind the avalanche prone locations will become more prevalent as the day progresses. The fresh wind slabs must be evaluated with care and prudence in particular on north to east to south facing aspects above approximately 2400 m. Single winter sport participants can release avalanches in some places. The avalanches can be triggered in the faceted old snow and reach large size. Backcountry touring calls for meticulous route selection. Until the temperature drops moist and wet avalanches are to be expected from the late morning, but they will be mostly small.

Outgoing longwave radiation during the night will be severely restricted. The surface of the snowpack will freeze to form a strong crust only at high altitudes and will already soften in the late morning. This situation will give rise to thorough wetting of the snowpack below the tree line. Weak layers exist in the old snowpack in particular on north facing slopes. In addition the fresh wind slabs are capable of being triggered.

The danger of dry avalanches will increase.