Middle Lys Valley

The danger of moist and wet avalanches will already exist in the early morning. Weak layers in the old snowpack are treacherous.

The danger of moist and wet avalanches will already exist in the early morning. Weak layers in the old snowpack are treacherous.

The surface of the snowpack will only just freeze and will already be soft in the early morning. As a consequence of warming during the day and solar radiation moist and wet avalanches are to be expected from the late morning, but they will be mostly small, especially on steep sunny slopes in particular below approximately 2900 m, as well as on steep shady slopes below approximately 2400 m. Backcountry tours and off-piste skiing should be concluded early. Single winter sport participants can release avalanches in some places. In particular on very steep northwest, north and northeast facing slopes the avalanches can be released in the weakly bonded old snow and reach medium size in isolated cases, caution is to be exercised in particular in gullies and bowls, and behind abrupt changes in the terrain, and at transitions from a shallow to a deep snowpack. Backcountry touring calls for meticulous route selection.

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 soften quickly. This situation will give rise to thorough wetting of the snowpack below the tree line. The old snowpack remains weakly bonded on shady slopes. In addition the sometimes deep wind slabs are capable of being triggered now as before.

15 cm of snow, but less in some localities, will fall on Friday above approximately 2500 m. The danger of dry and moist avalanches will increase during the day.