Západné Tatry

Watch out for persistent weak layers under the windblown slab.

Watch out for persistent weak layers under the windblown slab.

In all of our mountain ranges above the tree line, a second level of avalanche danger has been declared. The main avalanche problem is wind-blown snow. Especially the leeward sides of ridges, narrow couloirs and places under rock walls are dangerous. Here in particular, there are wind-blown slabs of varying hardness, which are also deposited on a permanently weak layer. These layers are weakly interconnected. Loosening is possible on steep slopes with little additional load. Avalanches of small to medium size are particularly dangerous here. Occasional spontaneous avalanches may occur on leeward steep slopes.

Snow cover is very diverse in the mountains. Wind-blown slabs of varying thickness and hardness alternate with older hard to icy ground. Underneath, soft, square-grained snows have been formed and maintained by the cold air. There may be several such layers in the cover. During the last snowfall period, between 5 and 10 cm of snow fell, but this is very unevenly distributed due to the strong, predominantly north-westerly winds. Locally, in narrow gullies, moguls and under rock walls, more than 50 cm of snow may be piled up. Mountain tops and ridges are blown into a hard and sometimes icy ground. In the forest zone, the snow is hard and load-bearing. There is hardly any continuous snow cover below 1000 m above sea level.

It persisted due to the cold air and strong winds. Compiled by: Pavel Beťko