Lechquellen Mountains

Trigger-sensitive snowdrift accumulations atop a weak old snowpack

Trigger-sensitive snowdrift accumulations atop a weak old snowpack

Marked weak layers in the old snowpack can still easily be triggered by one single winter sports enthusiast, especially on steep, little-skied slopes. The danger zones are not visible. Remote triggerings are possible. Fresh snowdrift accumulations occur increasingly in ridgeline terrain and in wind-loaded gullies and bowls. Avalanches which release can fracture to deeper layers in the old snowpack and grow to medium size. Whumpf noises and fractures when treading on the surface are alarm signals. Activities in backcountry demand careful evaluation of the terrrain and assessment of the dangers.

Yesterday’s stormy winds generated trigger-sensitive snowdrift accumulations, deposited on top of a weak old snowpack surface above the timberline, often on loose snow or surface hoar (particularly on steep shady slopes). Reports characterize the persistent weak layer problem as less marked in Lechquellgebirge than in the southern regions of Verwall, Silvretta and Rätikon.

Thin layers of cloud cover widespread, little sunshine, diffuse light conditions. Winds will slacken off measurably. Temperature at 2000m: -1 degree; at 3000m: -7 degrees. Moderate-strength S/SE winds at high altitudes.

Weak layers in the old snow can still be triggered by one single winter sports enthusiast. The likelihood of fresh drifts triggering will decrease only gradually.