Wind slab
- Alle Höhenlagen
Moderate avalanche danger will be encountered over a wide area.
The wind slabs of the last few days are in some cases still prone to triggering. They are to be found in particular adjacent to ridgelines and in gullies and bowls and generally in the high Alpine regions. They are to be evaluated with care and prudence in particular in very steep terrain. Single winter sport participants can release avalanches in some places, including medium-sized ones.
Snowpack As a consequence of northerly to northeasterly winds during the last few days, snowdrift accumulations have been generated at heightened altitudes which are prone to triggering in some places. Beneath the layer of fresh fallen snow from last weekend there is a layer of dust from the Sahara Desert evident in the Valais and in the Ticino more than anywhere else. Inside this zone of dust, a weak layer has been formed in some places from which isolated avalanches have been triggered during the last few days. More deeply embedded inside the snow cover, particularly on west-facing, north-facing and east-facing slopes above approximately 2200 m, there are weak layers prevalent over widespread areas. These weakened layers on the northern flank of the Alps and in the western part of the Lower Valais are generally heavily blanketed over by fresher snowfall and therefore, hardly likely to trigger from the weight of winter sports enthusiasts. In central and southern Grisons more than anywhere else, as well as in some places of northern Grisons and in the southern part of the Valais, these weakened layers inside the old snow cover are not blanketed over as heavily, making them more likely to trigger. This is the case particularly in places where the snow on the ground is shallow. Observed weather review Wednesday, 05.04.2023 Following a night of predominantly clear skies it was quite sunny. During the course of the day, increasing convective cloud build-up was registered. Fresh snow - Temperature At midday at 2000 m, between -2 °C in the Valais and in the southern regions, and -5 °C in the remaining regions of Switzerland. Wind Nocturnal winds were blowing at moderate strength, during the daytime predominantly at light strength, from northerly to northeasterly directions. Weather forecast through Thursday, 06.04.2023 Nighttime skies are expected to be generally clear. During the daytime hours it will be sunny to begin with. In the western regions clouds will move in starting in the morning, in the eastern and the southern regions in the afternoon. Fresh snow - Temperature At midday at 2000 m, between -2 °C in the southwestern regions and -4 °C in the northeastern regions. Wind Winds are expected to be blowing predominantly at light strength, also at moderate strength in elevated altitude zones, from westerly to northwesterly directions. Outlook through Saturday, 08.04.2023 On Thursday night and during the daytime hours on Good Friday, a small amount of snowfall is anticipated, with the exception of the furthermost southern regions. The snowfall level will lie at 1000 m. On the northern flank of the Alps, 10 to 20 cm of fresh fallen snow is expected, in the other regions of Switzerland 5 to 10 cm over far-reaching areas. Winds will be blowing predominantly at light strength from northwesterly directions. On Saturday in the eastern regions, skies will frequently be overcast. Above approximately 1200 m a small amount of additional snowfall is still expected. In the western and in the southern regions it will be quite sunny. Avalanche danger levels are not expected to change significantly. It is possible that danger will increase somewhat in the northern regions more than anywhere else on Good Friday as a result of fresh snowfall. Isolated wet-snow and gliding avalanches continue to be possible, in particular in the western regions and in the Valais, where temperatures will be somewhat higher and, particularly on Saturday, it will be sunnier.
Bulletin data: WSL Institute for Snow and Avalanche Research SLF (CC BY 4.0)