Allgäu Alps Central

Snowdrifts prone to triggering. Still possibility of gliding snow

Snowdrifts prone to triggering. Still possibility of gliding snow

Avalanche danger above 2200 m is considerable, below that altitude danger is moderate. Main problem: snowdrifts. Avalanche prone locations are found in wind-loaded, steep ridgeline terrain in N/E/SW aspects, behind abrupt changes in the terrain as well as in wind-loaded gullies and bowls. Here small slab avalanches can be triggered even by minimal additional loading such as a single skier. In addition glide snow avalanches can trigger naturally on steep smooth grass-covered slopes. These can be medium-sized; in isolated cases also large-sized. As a consequence of solar radiation moist loose snow avalanches can release in steep rocky terrain.

As of the onset of precipitations on Saturday until Sunday evening a total of 15-25 cm of new snow will fall widespread; in orographic barrier zones up to 35 cm. At lower altitudes the new snow is deposited atop bare ground. At higher altitudes it is transported by stormy westerly winds and is in places deposited atop snowdrifts, graupel or the loose fresh snow layers of Saturday. Soft layers that are prone to triggering are embedded in the accumulated snowdrift masses. The trigger-sensitivity increases with ascending altitude. In the uppermost part of the old snowpack there is a weak layer underneath the melt-freeze crust that is prone to triggering. Elsewhere the old snowpack is compact and stable. It is totally moist and wet down to the ground, thus enabling gliding movements over smooth ground.

The snowdrifts will settle fast at the beginning of the weak. Solar warming and sunshine will make wet snow the predominant problem again.