Middle Lys Valley

A clear night will be followed in the early morning by favourable conditions over a wide area, but the danger of wet avalanches will increase later.

A clear night will be followed in the early morning by favourable conditions over a wide area, but the danger of wet avalanches will increase later.

The conditions are spring-like. As the day progresses as a consequence of warming during the day and solar radiation there will be a rapid increase in the avalanche danger. Small and medium-sized moist and wet avalanches are possible, caution is to be exercised in particular on very steep east and west facing slopes below approximately 3600 m, and on north facing slopes below approximately 3200 m. Medium-sized to large natural avalanches are possible in isolated cases, in particular in case of releases originating from extremely steep starting zones at high altitude that still retain some snow. In particular at the base of rock walls the avalanche prone locations will become more prevalent in the afternoon. Most and wet avalanches can as before be released by a single winter sport participant and reach medium size. Backcountry tours and ascents to alpine cabins should be started very early and concluded timely. The Avalanche Warning Service currently has only a small amount of information that has been collected in the field, so that the avalanche danger should be investigated especially thoroughly in the relevant locality.

Outgoing longwave radiation during the night will be quite good. The surface of the snowpack will freeze to form a strong crust and will soften earlier than the day before. The backcountry touring conditions in the morning are generally favourable. The weather conditions facilitated a gradual strengthening of the snowpack. Below approximately 2200 m a little snow is lying. Snow cover varies depending on altitude and exposure; in many areas above 2300 m the snow cover is continuous and abundant. Use knives or crampons during excursions in the presence of smooth and hard snow in the morning.

The surface of the snowpack will cool hardly at all during the overcast night and will already be soft in the early morning. From the early morning as a consequence of the precipitation there will be a rapid increase in the danger of moist and wet avalanches.