Persistent weak layers
- All elevations
In the northeast a considerable avalanche danger will prevail. Weakly bonded old snow requires caution.
To some extent avalanches can be released in the old snowpack and reach medium size. These avalanche prone locations are to be found in particular at transitions from a shallow to a deep snowpack. In addition the older wind slabs are prone to triggering in some cases. They are to be found in particular in gullies and bowls, and behind abrupt changes in the terrain. The wind slabs are to be evaluated with care and prudence in very steep terrain. Careful route selection is recommended.
Snowpack On the northern flank of the Alps more than anywhere else, snowdrift accumulations have been generated by winds from varying directions over the last few days. These snowdrift accumulations are easily recognized for the most part, but in some places they are prone to triggering. On the northern flank of the Alps from the Bernese Oberland as far as Liechtenstein, in northern and in central Grisons, and in the Lower Engadine, fresh fallen snow and freshly generated snowdrift accumulations from the last few days blanket a weakly-layered snow cover. Avalanches can be triggered in transitions to old snowpack layers more than anywhere else, and then sweep away the entire snowpack, in particular in the relevant regions of Grisons. In the remaining regions of Switzerland there are older snowdrift accumulations evident from place to place which have been deposited on top of expansively metamorphosed (faceted) weak layers and are prone to triggering. In the northern and the furthermost western part of the Lower Valais the snowpack layering is most favourable and there are hardly any pronounced weak layers evident. Observed weather review Wednesday, 08.02.2023 It was sunny and cold. In the southern regions, increasing cloud cover moved in during the course of the afternoon. Fresh snow - Temperature At midday at 2000 m, between -5 °C in the northern regions and -9 °C in the southern regions. Wind
Weather forecast through Thursday, 09.02.2023 On Wednesday night, skies will be predominantly clear, only in the southern regions will skies be overcast, accompanied by light snowfall. During the daytime hours on Thursday it is expected to be sunny everywhere. In the mountains, good visibility will prevail above 1000 m. Fresh snow On the southern flank of the Alps, 2 - 5 cm of fresh snow is expected to fall during the nocturnal hours. Temperature At midday at 2000 m, approximately -8 °C. Wind
Outlook through Saturday, 11.02.2023 Following a night of predominantly clear skies it will be sunny on both following days. Temperatures will rise somewhat, on Friday the temperature at 2000 m will be approximately -1 °C. Mostly light winds will be blowing. Avalanche danger levels are expected to incrementally decrease.
Bulletin data: WSL Institute for Snow and Avalanche Research SLF (CC BY 4.0)