Persistent weak layers
- All elevations
Old snow often weak on steep shady slopes. Isolated glide-snow avalanches.
Old snow often weak on steep shady slopes. Isolated glide-snow avalanches.
Favourable conditions prevail. On high-altitude steep and shady slopes, weak layers at ground level can still be triggered in some places. Small-to-medium sized slab avalanches can be triggered especially by large additional loading in transitions from shallow to deep snow, e.g. at entries into gullies and bowls. In ridgeline terrain small fresh snowdrift accumulations require caution. On sunny slopes below about 2400m (shady slopes below about 2000m) isolated small-to-medium glide-snow avalanches are possible, particularly in the regions where snowfall has been heaviest on steep grass-covered slopes which have not yet discharged. Cracks in the snowpack are signals of danger.
The snowpack on most steep slopes is well consolidated and stable, but on high-altitude very steep slopes there are frequently covered weak layers of faceted crystals which are triggerable. On north-facing slopes and zones where the solar radiation is flat, the uppermost layers are generally still loose. On steep sunny slopes there is often a thin melt-freeze crust. At low and intermediate altitudes the snowpack is moist, which furthers the gliding movements of the snowpack. Small freshly generated snowdrifts in ridgeline terrain become more prone to triggering with ascending altitude.
Above the fog and particularly in the southern regions it will turn quite sunny. Brisk northerly winds make it seem colder than it is. Temperature at 2000 m: -1 degree. Brisk northerly winds at high altitudes.
It will remain sunny and cold during the day. Avalanche danger is not expected to change significantly.
Bulletin data: Avalanche Warning Service Vorarlberg (CC BY 4.0)