The old snowpack is generally poorly constructed and requires defensive behaviour
The avalanche risk increases rapidly with altitude and is considerable above around 2000 metres and low below. In some places, slab avalanches can be triggered by individuals and can be of medium size. Take care in transitions from a little to a lot of snow and in the blown-in entrance areas to steep gullies as well as behind terrain edges, where prone-to-triggering snow packs are located. These continue to grow from late afternoon onwards. They are partly covered in snow and therefore difficult to recognise. Avalanches that are triggered near the surface in fresh wind slabs can tear through to deeper weak layers. Whumpfing collapsing sounds when stepping on the snowpack can indicate danger. Remote triggering is possible in isolated cases.
Snowpack
The snowpack is highly variable and areas with little snow alternate with considerable snowdrift accumulations. In general, 10-20 cm of fresh new and drift snow lies on top of older, mostly hardness wind slabs, which are in the initial stages of kinetic metamorphism. Below this, the old snowpack consists of deep rime and angular forms interspersed with crusts. Fractures in the persistent weak layer usually occur around the uppermost crust, but can also entrain deeper layers. During the night, melt-freeze crusts and surface hoar form, while during the day the snowpack is slightly soaked on the sunny slopes. The snow depth is well below average at all altitudes.
Tendency
The avalanche danger increases with the Föhn storm on Tuesday.
Danger level
2000m
Avalanche Problem
Persistent weak layer
2000m
The old snowpack is generally poorly constructed and requires defensive behaviour
The avalanche risk increases rapidly with altitude and is moderate above around 2000 metres and low below. Slab avalanches can only be triggered by individuals in a few places but can reach medium size if they tear through the old snowpack. Some avalanche prone locations are covered in snow and difficult to recognise. Take particular care in the north to east aspects, especially in the snow-covered entrance areas to steep gullies and bowls, behind terrain edges and at the transition from little to more snow. Whumpfing collapsing sounds when stepping on the snowpack can indicate danger. In addition to the risk of burial, the risk of being swept away and falling should also be taken into account.
Snowpack
The snowpack is highly variable and areas with little snow alternate with considerable snowdrift accumulations. Some of these are covered by a few centimetres of settled new fallen snow. Older snowdrift accumulations have been transformed in places and are soft and in places hard as a board. Underneath, the old snowpack consists of deep rime and angular forms interspersed with crusts. Breaks in the persistent weak layer usually occur around the uppermost crust. During the night, melt-freeze crusts and surface hoar form, while during the day the snowpack is slightly soaked on the sunny slopes. The total snow depth is well below average.
Tendency
The avalanche danger increases slightly with the foehn storm on Tuesday.
Danger level
2200m
Avalanche Problem
Persistent weak layer
2200m
Small drift snow accumulations on weak old snowpack
The avalanche risk is low. In the extended northern and eastern exposures above around 2200 m, small slab avalanches can still be triggered by individuals in a few places. Danger areas are located at the transition from little to more snow and generally next to blown-off areas. Some of the avalanche prone locations are thinly covered with snow and difficult to recognise. The risk of falling and injury generally outweighs the risk of burial.
Snowpack
A few centimetres of settled new fallen snow cover previously bare ground or a hard, sometimes icy surface of old snow. On shady slopes in particular, small snowdrift accumulations usually overlay a weak old snowpack consisting of an alternation of crusts and faceted crystals or deep rime. During the night, melt-freeze crusts and surface hoar form, while during the day the snowpack is soaked on the sunny slopes.
Tendency
The avalanche danger increases slightly with foehn storms.
Danger level
Low avalanche danger and lack of snow
The avalanche risk is low. There is very little snow, only in the entrance areas to steep, on shady slopes can there be pillows of wind drifted snow. Otherwise, the danger of injury from stones and falling on icy surfaces outweighs the risk of burial.
Snowpack
On shady slopes and flat ground, traces of settled new fallen snow or thin wind slabs cover the previously apery meadows or icy old snow surface. Edged persistent weak layers weaken the thin snow base, fundament if present. Thin melt-freeze crusts and surface hoar form during the night; during the day, the surface of the snowpack is moistened on the sunny slopes.
