Middle Lys Valley

Afternoon: Wind and new snow above approximately 2300 m.

Afternoon: Wind and new snow above approximately 2300 m.

On Sunday it will be cloudy. The surface of the snowpack will cool hardly at all during the overcast night. In the late morning the natural activity of small and medium moist and wet avalanches will only slowly increase. 15 to 25 cm of snow, and even more in some localities, will fall from the afternoon above approximately 2300 m. This situation will give rise to gradual moistening of the snowpack below approximately 2400 m. At low altitude and on very steep slopes small to medium-sized moist snow slides and avalanches are possible as a consequence of the rain. In some places moist and wet avalanches can be released in deep layers reach medium size in particular on very steep northeast, north and northwest facing slopes. In addition sometimes avalanche prone wind slabs will form in particular above the tree line in the evening. Night: The avalanche danger will increase.

The snowpack will be wet all the way through at low and intermediate altitudes. In the last few days the natural activity of medium wet and gliding avalanches has gradually increased. Several medium-sized to large ground avalanches have been released since Tuesday. This applies in particular on very steep northeast, east facing slopes. At higher altitudes, snow cover becomes thinner and patchy; it is better at mid-altitudes, which are less exposed to the wind. The surface snowpack changes rapidly depending on the aspect and gradient: crusts of various types and thicknesses alternate. In steep terrain there is a danger of falling on the hard crust, especially adjacent to ridgelines and in pass areas. Weak layers exist in the snowpack in particular on steep shady slopes. Below approximately 1800 m hardly any snow is lying.

The large quantity of fresh snow and the wind slabs that are forming at intermediate and high altitudes are bonding poorly with the old snowpack. Medium-sized and, in isolated cases, large dry and wet avalanches are possible as a consequence of new snow and strong wind. Already in the morning, Fast increase in avalanche danger level, especially in the areas bordering Piedmont.