With ascending altitude, fresh snowdrifts are increasingly prone to triggering. One single winter sports enthusiast can trigger slab avalanches. Danger zones occur particularly on steep shady slopes, but also in wind-loaded gullies and bowls and behind sudden drops in the terrain. The old snow can trigger avalanches particularly from large additional loading. The avalanche prone locations are not visible, especially on steep shady slopes. If a release sweeps along the entire snowpack with it, the avalanche can grow to medium size. Activities in backcountry demand careful evaluation of the terrain and the dangers as well as a large measure of restraint.
Snowpack
The 15-20cm of fresh snow and snowdrift accumulations at high altitudes from recent days lie deposited on top of a weak old snowpack surface, especially on steep shady slopes. In some ridgeline zones, in wind-loaded gullies and bowls and behind sharp drops in the terrain, freshly generated snowdrifts have accumulated which are prone to triggering.
Tendency
Fresh snow and drifts deposited atop the old snowpack surface remain prone to triggering.
Danger level
treeline
Avalanche Problem
Wind slab
Treeline
Rising danger above the timberline due to fresh snow and snowdrifts
Fresh snow and small fresh snowdrifts are easily triggerable in steep ridgeline terrain and behind sharp drops in the terrain. One single winter sports enthusiast can trigger small-sized, in isolated cases medium-sized slab avalanches. Other danger zones occur on extremely steep, mostly shady slopes. In isolated cases, small avalanches can be triggered in the old snow in those places. Such avalanche prone locations occur particularly in transitions from shallow to deep snow, for example, at entry points into gullies and bowls. Apart from the risks of being buried in snow masses, the danger of being swept along and forced to take a fall also require caution.
Snowpack
The 10-20cm of fresh fallen snow often lies deposited atop loosely-packed fresh snow or drifts from recent days and a frequently melt-freeze encrusted old snowpack. In some places, the surface hoar has now been blanketed. Above all else, on steep shady slopes the often unfavorable intermediate layers inside the old snowpack have persisted. On south-facing slopes the fresh snow often fell on bare ground.
