In the lower part of the snowpack there are weak layers of expansively metamorphosed (faceted) crystals on west-facing, north-facing
and east-facing slopes above approximately 2200 m in nearly all regions of Switzerland. From central Valais as far as Grisons,
as well as in general in those places where the snow is shallow, the snowpack layering is least favourable. In the western
part of Lower Valais and on the northern flank of the Alps, the weak old snow is frequently blanketed over by thick layers.
In general, spots where the old snowpack is shallow can be most easily triggered.
As a result of strong to storm-strength winds on Friday, a great deal of snow will be transported. The snowdrift accumulations
are prone to triggering.