Lechquellen Mountains

Fresh and older snowdrift accumulations trigger-prone

Fresh and older snowdrift accumulations trigger-prone

Fresh and older snowdrifts are the main danger, often blanketed and hard to recognize. Danger zones occur in steep ridgeline terrain, behind discontinuities and in wind-loaded gullies and bowls and increase with ascending altitude. A small-to-medium slab avalanche or loose-snow avalanche can be triggered by 1 person (in high-alpine terrain larger). Activities in backcountry demand experience in outlying terrain and the ability to assess avalanche dangers on-site. Glide-snow avalanches can trigger below 2600 m at any time of day or night and reach large size. Caution urged below glide cracks.

Fresh snow and fresh snowdrifts lie deposited on high-altitude shady slopes atop soft layers or atop older snowdrifts on high-altitude shady slopes, otherwise atop a hard old snowpack surface. Bonding deteriorates with ascending altitude. Weak trigger-prone layers are evident inside the fresh snowdrift accumulations. On high-altitude shady slopes the surface is powdery, elsewhere there are often melt-freeze crusts and wind crusts evident. Warm ground and the wet snowpack base reinforce the gliding movements of the entire snowpack. Frequent glide-snow avalanches have been reported.

Nocturnal hours: Heavy cloud cover, not much longwave outgoing radiation. Monday daytime: Cloud but dry, little sunshine and then, only weak. Im the Rätikon and Silvretta, peaks can be shrouded in clouds. At 2000 m: -2 to 0 degrees. Moderate-to-strong southerly winds.

In the Rätikon, Silvretta and Verwall a bit of minor snowfall is possible, elsewhere it will be dry. Strong southerly winds will continue to transport the snow. Danger of dry-snow avalanches is not expected to change. Glide-snow avalanches are still possible.