Persistent weak layers
- Above treeline
- Size
- 2
Stability: poor · Frequency: some
Weakly bonded old snow is to be evaluated with care and prudence.
Stability: poor · Frequency: some
Stability: very poor · Frequency: few
Weakly bonded old snow is to be evaluated with care and prudence.
Avalanche prone weak layers exist in the centre of the snowpack in particular on steep shady slopes. Avalanches can in some places be released by small loads and reach medium size. This applies in particular at transitions from a shallow to a deep snowpack, when entering gullies and bowls for example. Avalanche prone locations are to be found in particular on steep west, north and east facing slopes above the tree line, this also applies on steep shady slopes in areas close to the tree line. Whumpfing sounds and the formation of shooting cracks when stepping on the snowpack can indicate the danger. Only isolated gliding avalanches are possible, even medium-sized ones. This applies on steep grassy slopes below approximately 2400 m. Defensive route selection is important.
The weather conditions will bring about a gradual stabilisation of the snowpack. The somewhat older wind slabs of the last few days are lying on top of a weakly bonded old snowpack in particular on west to north to east facing aspects above the tree line. Weak layers exist deep in the old snowpack also on south facing slopes. This applies in particular in high Alpine regions. The old snowpack will be moist at low and intermediate altitudes. This applies in particular on south facing slopes. Above the tree line snow depths vary greatly, depending on the infuence of the wind.
Gradual decrease in avalanche danger.
Bulletin data: Avalanche Warning Service Tirol, avalanche.report (CC BY 4.0)