Wind slab
- Above treeline
- Size
- 2
Stability: poor · Frequency: some
Freshly generated snowdrifts require attentiveness.
Stability: poor · Frequency: some
Stability: fair · Frequency: few
Freshly generated snowdrifts require attentiveness.
Avalanche danger above the treeline is moderate, below that altitude danger is low. Snowdrift accumulations above the treeline can be triggered by one single skier and in isolated cases grow to medium size. Danger zones occur especially behind protruberances in the landscape, in gullies and bowls, and on wind-loaded slopes. Size and frequency of these avalanche prone locations tend to increase with ascending altitude. They have been blanketed in some places, making them difficult to recognize. Below the treeline avalanche danger is low. At low altitudes small glide-snow avalanches are possible on steep grass-covered slopes.
Since yesterday there has been 25-30cm of fresh now registered. Due to strong-to-storm strength W/NW winds there has been wide-reaching transport. During the daytime due to brisk-to-strong NW winds, and tomorrow W/SW winds, additional trigger-sensitive snowdrift accumulations have been generated and will continue to be. The drifts lie deposited atop a weak old snowpack on high-altitude shady slopes, on sunny slopes often atop a thin melt-freeze crust. Weak layers can occur on high altitude slopes where the old snowpack was previously loose and also inside the snowdrifts themselves. During the daytime, in addition, graupel showers will pass through. At low altitudes the fresh snow and drifts lie deposited atop a moistened old snowpack surface with better consolidation.
Dry weather far and wide in the mountains, lots of cloud cover and diffuse visibility but generally free of fog at summit levels. Sunshine only intermittently. The heavy frost will become milder. On Saturday night, snowfall is anticipated which can be persistent and heavy. At 2000m: -6 degrees. Moderate NW winds at high altitudes. In the evening, winds will shift to westerly and during Saturday night intensify.
Following a brief improvement in weather conditions on Saturday, renewed precipitation will set in during Saturday night, accompanied by strong-to-storm strength W/NW winds. Avalanche danger levels are expected to increase significantly over widespread areass.
Bulletin data: Avalanche Warning Service Vorarlberg (CC BY 4.0)