Swiftly rising daytime avalanche danger. Near-surface weak layers can often be triggered by winter sports enthusiasts.
Following a night of clear skies, generally favorable backcountry touring conditions in early morning. However, avalanche danger, particularly on very steep north-facing slopes, increases rapidly at 1800-2200m due to solar radiation and daytime warming in all aspects, particularly below 2400m, also above that altitude on very steep sun-exposed slopes. Naturally triggered avalanches can be expected; persons can trigger wet-snow slab avalanches. If near-surface avalanches fracture down to deeper layers of the snowpack they can, in isolated cases, grow to large size. In addition, winter sports enthusiasts can trigger near-surface weak layers on high-altitude shady slopes. Danger zone are impossible to recognize. Attention: danger of taking a fall on hardened snowpack surfaces on steep slopes.
Snowpack
Good nocturnal outgoing longwave radiation will generate a gradually thicker melt-freeze crust which, however, will swiftly soften up during the course of the day. At altitudes between 1800 and 2200m the snowpack (also on north-facing slopes) is thoroughly wet and the ground-level rotten snow is extremely prone to triggering already in early morning. On high-altitude shady steep slopes there are unfavorable intermediate layers in the uppermost metre of the snowpack which in places can be triggered. A solid mid-section of compact layers inside the snowpack blankets a fundament of buried hoar and faceted crystals.
Tendency
Due to reduced nocturnal longwave outgoing radiation on Thursday night, wet-snow problem will predominate already in early morning on Friday.
EARLIER Danger level
Avalanche Problem
Gliding snow
LATER Danger level
Avalanche Problem
Wet snow
Main danger: wet-snow avalanches
Avalanche danger is low in the morning and rises to moderate during the course of the day. On steep slopes with lots of snow and a smooth underground which have not yet discharged, glide-snow avalanches can trigger at any time of day or night in all aspects. Zones below glide cracks should be avoided. Due to daytime warming and solar radiation, wet loose-snow avalanches can trigger naturally, particularly on extremely steep slopes. Avalanches can grow to medium size and place exposed hiking trails at risk.
Snowpack
South-facing slopes are frequently bare of snow. Where there’s a snowpack on the ground, it’s thoroughly wet.
Tendency
As a result of dropping temperatures, avalanche danger will decrease on Friday.
