Persistent weak layers
- Above 2,000 m
- Dimensione
- 3
Stability: poor · Frequency: some
Weakly bonded old snow represents the main danger.
Stability: poor · Frequency: some
Weakly bonded old snow represents the main danger.
Avalanches can be released in the old snowpack and reach large size. This applies even in case of a single winter sport participant. The avalanche prone locations are to be found on west, north and east facing slopes above approximately 2000 m. Caution is to be exercised in particular at transitions from a shallow to a deep snowpack. Whumpfing sounds can indicate the danger. Remotely triggered avalanches are possible in isolated cases. As a consequence of warming during the day and the solar radiation, the likelihood of slab avalanches being released will increase a little also on steep sunny slopes at elevated altitudes. Backcountry tours and off-piste skiing should be concluded timely.
Distinct weak layers exist in the old snowpack in particular on west, north and east facing slopes. This applies especially above approximately 2000 m. Towards its surface, the snowpack consists of faceted crystals, especially on shady slopes at elevated altitudes. Outgoing longwave radiation during the night will be good. The surface of the snowpack will freeze to form a strong crust. In steep terrain there is a danger of falling on the hard snow surface. The weather conditions as the day progresses will give rise to slight softening of the snowpack in particular on very steep sunny slopes.
Weakly bonded old snow requires caution. Single winter sport participants can release avalanches as before. Hardly any increase in danger of wet avalanches as a consequence of warming during the day and solar radiation.
Bulletin data: Avalanche Warning Service South Tyrol, avalanche.report (CC BY 4.0)