Weisseck, Muhr Valley

Fresh snowdrifts in high alpine regions, poor visibility

Fresh snowdrifts in high alpine regions, poor visibility

Avalanche danger is MODERATE above 2000 m, below that altitude danger is LOW. Fresh snowdrifts have been deposited in gullies and north-facing bowls, often triggerable as a small-to-medium avalanche by minimum additional loading. Poor visibility makes on-site evaluation more difficult. Due to diffuse radiation and daytime warming, loose-snow and isolated slab avalanches or glide-snow avalanches (mostly small, seldom medium) can trigger in extremely steep terrain. Above 2400 m on shady slopes there are isolated danger zones where by large additional loading (a fall, stomping, superficial slab) a slab avalanche can trigger in the old snow which then can grow to large size.

There has been 10-25 cm of fresh snow registered atop a predominantly well consolidated base, in exposed regions the snow is bonded by winds from W/NW. Snowdrifts are small, particularly on N/E facing slopes. Trigger-sensitivity increases with ascending altitude. Otherwise the snowpack is encrusted in early morning, then softens during the daytime. The old snowpack is generally compact, in places a weak layer has formed around the Sahara-dust encrusted layer, but is hardly triggered, except by large additional loading (e.g. an avalanche).

On Wednesday the peaks will often be veiled in clouds, visibility is reduced. Most rainfall/snowfall is expected in the Northern Alps. The snowfall level will ascend from 1200m to 1700 m in the course of the day. In high alpine regions, a moderate northerly wind will be blowing. At 2000 m: -4 to 0 degrees; at 3000 m, -8 degrees. On Thursday, frequent sunshine. During the course of the day, a few convective clouds will accumulate, visibility will be adequate. A light to moderate northerly wind will be blowing. At 2000 m: -2 to +3 degrees; at 3000 m: -5 degrees.

On Thursday, numerous loose-snow avalanches are expected in sun-drenched steep terrain. Small snowdrift problem, the trigger-sensitivity will swiftly recede. Wet-snow problem at intermediate altitudes due to the fresh fallen snow rapidly becoming thoroughly wet.