Middle Lys Valley

The weather will be warm. Moist and wet avalanches as the day progresses.

The weather will be warm. Moist and wet avalanches as the day progresses.

Even at night, air temperatures were positive above 3000 m. In particular above approximately 2500 m and shady slopes: The early morning will see favourable conditions for a short time, but the danger of wet and gliding avalanches will increase later. As a consequence of warming and solar radiation, the natural activity of medium moist and wet avalanches will rapidly increase, in particular on very steep sunny slopes. This also applies at the base of rock walls, including on very steep shady slopes at intermediate altitudes. Especially on extremely steep slopes avalanches can release the wet old snow as well and reach large size in isolated cases. Backcountry tours and off-piste skiing should be started and concluded very early.

The surface of the snowpack will freeze to form a strong crust only at high altitudes and will soften quickly. In the last few days the natural activity of medium wet and gliding avalanches has gradually increased. The snowpack will be wet all the way through at low and intermediate altitudes. 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. As a consequence of mild temperatures and solar radiation the snowpack settled. These spring-like weather conditions will give rise to increasing consolidation of the snowpack. Below approximately 1800 m hardly any snow is lying.

The danger of moist and wet avalanches will persist.