Wind slab
- Above 1,800 m
Snowpack
Deep layers of the snowpack are compact in many places. However, around the crusts in the upper third of the old snowpack, weak layers with a sometimes faceted crystal structure are deposited.
A lot of fresh snow fell on and to the south of the Main Alpine Ridge at the weekend. The southerly winds led to the formation of extensive wind slabs at high altitudes. Many naturally triggered avalanches, some of them very large, occurred on Sunday, particularly in southern Upper Valais.
In the north, the loose snow of the past week was heavily transported to below the tree line by the storm-force Bise wind. The snowdrift was widely deposited on loose snow on north-facing slopes, locally also on surface hoar. As a result, the recent wind slabs were often prone to triggering and many were released by people. The wind slabs are now covered with new snow in many places, making them difficult to recognise.
Gliding avalanches are still possible, primarily on east-, south- and west-facing slopes below approximately 2400 m and more rarely on north-facing slopes. These may be large.
Weather forecast until Tuesday, 12.03.2024
It will be fairly sunny in the south, with winds tending to be from the north. Elsewhere, it will be very cloudy, with some snow falling above approximately 1300 m.
New snow
From Monday afternoon to Tuesday afternoon, the following amounts of fresh snow are expected:
Temperature
At midday at 2000 m, between -3 °C in the north and -1 °C in the south.
Wind
Weather review for Monday, 11.03.2024
A three-day period of storm-force southerly winds and a lot of new fallen snow in the south ended during the night. It was quite sunny in the early morning, turning increasingly cloudy from the northwest in the afternoon as the first showers arrived.
New snow
Since Friday, the following amounts of snow have fallen above approximately 1600 m, most of it on Sunday:
Temperature
At midday at 2000 m, around -3 °C.
Wind
Trend until Thursday, 14.03.2024Wednesday
In the north, it will snow during the night above approximately 1300 m. The quantities are still uncertain. During the day, it will be fairly sunny in the west, with clear spells in the north. It will be fairly sunny in the south, with winds tending to be from the north.
In the north, the danger of dry avalanches will increase somewhat. It will decrease in the south. Individual gliding avalanches will still be possible, some of which could be large.
Thursday
With light winds, it will be mostly sunny and increasingly mild as the day progresses.
The danger of dry avalanches will decrease. Individual gliding avalanches will still be possible, some of which could be large.
Bulletin data: WSL Institute for Snow and Avalanche Research SLF (CC BY 4.0)