Persistent weak layers
- Alle Höhenlagen
Still trigger-sensitive intermediate layers on high-altitude shady slopes
Still trigger-sensitive intermediate layers on high-altitude shady slopes
Main problem: weak layers in upper part of the snowpack. Near ridgelines they can be triggered as a slab avalanche by winter sports enthusiasts on steep shady slopes, but releases tend to remain small. Due to solar radiation and daytime warming, small loose-snow avalanches are possible on sunny slopes. Below 2200 m on sunny steep grassy slopes, glide-snow avalanches are possible.
Fresh snow and snowdrifts from the beginning of the week lie deposited atop unfavourable layers, often of surface hoar, melt-freeze crusts or softened layers. Bonding of fresh snow and drifts to these layers and also inside the snowpack itself is frequently poor. At lower and intermediate altitudes the snowpack was able to settle somewhat, and consolidate. On shady slopes and with ascending altitude this process is taking longer, also due to the lower temperatures. On very steep sunny slopes a thin melt-freeze crust has formed on the surface. The snowpack is often still powdery.
Nocturnal hours: clear, dry nighttime skies, and cold. Saturday: temporarily windy, a few clouds in the morning. In the afternoon, sunnier, temperatures rising. At 2000 m: -7 to 0 degrees. Moderate to brisk N/NW winds.
Sunday will be sunny but for a few cirrus clouds. Cold NE winds. Avalanche danger will slowly diminish.
Bulletin data: Avalanche Warning Service Vorarlberg (CC BY 4.0)