Wind slab
- Above treeline
- Size
- 2
Stability: poor · Frequency: some
Caution urged towards fresh drifts at high altitude. Increasingly frequent slides and glide-snow avalanches due to rain impact.
Stability: poor · Frequency: some
Stability: very poor · Frequency: few
Cloudy skies at night with increasingly heavy precipitation, initially falling as snow below 600m. At high altitudes, milder. The snowfall level will ascend in the latter part of the night to nearly 1500m. On Sunday morning a warm front will bring light rainfall to over 2000m. In the afternoon, dry, pleasant, mild. At 2000m: 0 to +5 degrees. Strong to stormy W/SW winds at high altitude.
Storm-strength southerly winds will transport the snow and generate new drifts, thus, avalanche danger can increase regionally.
Caution urged towards fresh drifts at high altitude. Increasingly frequent slides and glide-snow avalanches due to rain impact.
Fresh and older snowdrifts can be triggered even by one sole skier. Danger zones occur particularly on steep shady slopes, in wind-loaded gullies and bowls and behind protruberances in the terrain. Size and frequency of danger zones tend to increase with ascending altitude. In addition, in steep shady terrain at high altitudes where the snow is shallow, isolated transitions from shallow to deep snow can trigger avalanches in the weak old snow by large additional loading. On steep grass-covered slopes, slides and small glide-snow avalanches are possible, particularly in sunny aspects. Caution urged below glide cracks.
Fresh snow and drifts lie deposited atop an unfavorable, expansively metamorphosed old snowpack surface, often atop surface hoar, on shady slopes in particular. Also inside the snowdrifts themselves there are frequently trigger-sensitive intermediate layers evident. On sunny slopes, bonding to the old snowpack surface is better. At high altitudes, weak layers near the ground and faceted intermediate layers inside the old snowpack can often be triggered. In regions where there has been rain impact the snowpack is being temporarily weakened.
Bulletin data: Avalanche Warning Service Vorarlberg (CC BY 4.0)