Weisseck, Muhr Valley

Assess snowdrift accumulations on steep shady slopes with caution

Assess snowdrift accumulations on steep shady slopes with caution

Avalanche danger above 2000m is moderate, below that altitude danger is low. Snowdrift accumulations can in some places be triggered even by one sole skier, esp. in steep ridgeline terrain, on the Main Tauern Ridge also on slopes behind protruberances in the landscape which are distant from ridgelines.Avalanches can grow to medium size if they fracture to more deeply embedded layers. Trigger points lie esp. in transitions from shallow to deeper snow or in the opposite direction, esp, on very steep north-facing slopes. Naturally triggered small glide-snow avalanches are possible in isolated cases.

Southerly foehn winds will generated shallow snowdrift accumulations on shady slopes which atop the loose, faceted old snowpack surface will be prone to triggering. Inside the old snowpack on very steep shady slopes there are weak layers of faceted crystals. On the one hand, the snow was able to metamorphose esp. where snow is shallow; on the other, below the near-surface melt-freeze crust there are also faceted crystals. Snowdrifts can form a slab on the surface above the faceted crystals. On shady slopes loose snow is still evident, on sunny slopes it is turning to firn.

On Friday, high-altitude clouds above summit level, light conditions will become diffuse, visibility not be hampered. Only in the Lungau will low-lying clouds disturb somewhat. On the Main Tauern Ridge, storm-strength southerly foehn winds will reach 70-90 km/hr, in the other massifs only light to moderate southerly winds. At 2000m: -5 degrees in the Nockberge, elsewhere -1 degree; at 3000m: -6 degrees.

As foehn winds persist, snowdrift problem will intensify. Otherwise no change expected.