Persistent weak layers
- Above treeline
- Size
- 3
Stability: very poor · Frequency: some
Shady slopes: Weakly bonded old snow requires caution. Very steep sunny slopes: Increase in danger of wet avalanches as a consequence of warming.
Stability: very poor · Frequency: some
Stability: very poor · Frequency: some
Distinct weak layers exist in the old snowpack in particular on west, north and east facing slopes. Outgoing longwave radiation during the night will be reduced at times. The weather conditions as the day progresses will give rise to thorough wetting of the snowpack. This applies on very steep sunny slopes below approximately 2200 m.
The activity of wet avalanches will increase.
Shady slopes: Weakly bonded old snow requires caution. Very steep sunny slopes: Increase in danger of wet avalanches as a consequence of warming.
Avalanches can be released in the old snowpack and reach large size in isolated cases on west, north and east facing slopes. This applies in case of a single winter sport participant. The avalanche prone locations are to be found in particular above the tree line. In their paths avalanches can entrain the wet snow. This extends the avalanche runout distances. As a consequence of warming during the day and solar radiation small and medium-sized wet avalanches are possible. This applies in particular on very steep sunny slopes below approximately 2200 m. The runout zones are to be treated with caution.
Bulletin data: Avalanche Warning Service Tirol, avalanche.report (CC BY 4.0)