Caution: fresh drifts blanket weak old snow layers.
With ascending altitude, fresh and older snowdrift accumulations are prone to triggering. One single winter sports enthusiast can trigger slab avalanches. Danger zones occur in steep ridgeline terrain, in wind-loaded gullies and bowls, and behind drops in the terrain. Triggered releases can sweep away more deeply embedded layers inside the snowpack and grow to medium size. Such danger zones are not visible, particularly on steep shady slopes. Activities in backcountry demand careful evaluation of the terrain and the avalanche dangers, as well as restraint. On sunny slopes, small loosely-packed slides can trigger naturally during the course of the day.
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
Avalanche danger will recede only gradually.
Danger level
treeline
Avalanche Problem
Wind slab
Treeline
Caution: snowdrift accumulations prone to triggering
Small fresh and older snowdrifts in steep ridgeline terrain and behind drops in the landscape are prone to triggering. One single winter sports enthusiast can trigger small, in isolated cases medium-sized slab avalanches. Other danger zones occur on extremely steep, mostly shady slopes. In isolated cases there, small avalanches can be triggered in the old snow. These avalanche prone locations occur most often 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 dangers of being swept along and forced to take a fall also require caution. On sunny slopes, small-sized loosely-packed snowslides can trigger naturally during the course of the day.
Snowpack
Up to 15cm of fresh snow often lies deposited atop loosely-packed fresh snow or drifts from recent days and a frequently melt-freeze encrusted old snowpack surface. In some places, surface hoar has been blanketed. Particularly on shady steep slopes, unfavorable intermediate layers have often persisted. On south-facing slopes and at lower altitudes, the fresh snowfall often was deposited on bare ground.
