Wind slab
- Above 1,800 m
Snowpack
Large wind slabs will develop in the north on Friday. New snow and wind slabs are prone to triggering. In southern Valais, Grisons and Ticino, strong northerly winds will transport the little new snow and the loose old snowpack, leading to wind slabs that are prone to triggering in these regions.
South of a line from the Rhone to the Rhine, there are still weak layers in the lower part of the snowpack. In the last few days, only a few avalanches have been triggered deep in the old snowpack, but these were dangerously large. With the new snow and fresh wind slabs, the triggering of avalanches in deep layers of the snowpack is becoming more probable again.
Only a few gliding avalanches have been reported recently – although some of them were large.
Weather forecast to Friday
Widespread snowfall during the night, mainly in the west and north. During the day, it will be mostly sunny in the west and south. It will be cloudy in the east and some more snow will fall. The snowfall level will be at low altitude.
Fresh snow
Temperature
At midday at 2000 m, -10 °C in the north and -7 °C in the south.
Wind
Weather review for Thursday
During the night, some snow fell in the west and north above 1500 m. In the morning it was cloudy with bright spells in Grisons. In the afternoon, snow began to fall again from the north.
Fresh snow
From Wednesday afternoon to Thursday afternoon, the following amounts of new snow were recorded above approximately 1500 m:
Temperature
At midday at 2000 m, around -2 °C.
Wind
Moderate from the southwest.
Outlook
On Saturday and Sunday it will be mostly sunny in the mountains. The zero-degree level will increase appreciably: in the west and south to around 2200 m, in the east gradually towards 1600 m. The wind will ease. On Saturday there will be a light to moderate north to northeasterly wind, which will turn westerly to northwesterly on Sunday.
The avalanche danger will decrease. As a consequence of warming and solar radiation, loose snow avalanches are to be expected, especially on Saturday in all regions with fresh snow.
Bulletin data: WSL Institute for Snow and Avalanche Research SLF (CC BY 4.0)