Persistent weak layers
- Above treeline
- Size
- 2
Stability: very poor · Frequency: few
Stability: very poor · Frequency: few
Stability: very poor · Frequency: few
Weak layers in the old snowpack can be released in isolated cases even by individual winter sport participants in particular on steep shady slopes. This applies in particular in little used terrain, as well as in areas where the snow cover is rather shallow above the tree line. Avalanches can penetrate even deep layers and reach a dangerous size. Distinct weak layers in the old snowpack necessitate defensive route selection.
The old snowpack is faceted and weak and its surface has a strong crust. The snowpack is hard and its surface has a melt-freeze crust that is strong in many cases. This applies in particular on steep sunny slopes above the tree line. The surface of the snowpack will soften during the day. Sunshine and high temperatures will give rise as the day progresses to a loss of strength within the snowpack over a wide area in particular on very steep sunny slopes.
Bulletin data: ARPAV Centro Valanghe di Arabba (via EAWS / avalanche.report)