Werdenfels Alps

Fresh snowdrifts prone to triggering

Fresh snowdrifts prone to triggering

At high altitudes avalanche danger is considerable, below that it is moderate. Main problem: freshly generated snowdrift accumulations. Avalanche prone locations are generated in particular in steep terrain adjacent to ridgelines as well as in gullies and bowls. However, snowdrifts that are prone to triggering are also found distant from ridgelines behind protuberances and abrupt slope discontinuities, where medium-sized slab avalanches can be triggered even by one sole skier. Frequency and size of the danger zones increase with ascending altitude. Mostly small, in isolated cases also medium-sized, glide snow avalanches can trigger on steep smooth grass-covered slopes that have not yet discharged. Below 1600 m only small avalanches are to be expected due to the shallowness of the snowpack.

At high altitudes stormy westerly wind generates more and more fresh snowdrift accumulations which bond only poorly with the partly encrusted or icy old snowpack surface; the snowdrifts are prone to triggering. At intermediate altitudes rain thoroughly moistens the old snowpack which is shallower than usual. A wet snow layer forms at the ground which promotes gliding movements of the snow masses. The ground is becoming increasingly bare. All in all the old snow has settled well and the layers embedded in the snowpack have bonded and disintegrated. Only in the old snowpack at high altitude have weak layers consisting of faceted crystals persisted in patches.

During the next few days, attention will have to be paid to the snowdrift avalanche problem due to additional new snow at high altitude and stormy westerly wind.