Weisseck, Muhr Valley

Isolated persistent weak layer on shady high altitude slopes

Isolated persistent weak layer on shady high altitude slopes

Weak layers inside the old snowpack can on shady slopes above approximately 2300 m still be triggered, particularly on wind-protected slopes at the foot of rock walls or behind abrupt discontinuties in the terrain. Danger zones are rare, difficult to recognize. Avalanches can grow to medium size. The quite mild temperatures and a bit of rainfall starting in late afternoon below 1700 m make small wet loose-snow slides likely in extremely steep terrain. In addition, glide-snow avalanches on steep grassy slopes in all aspects are possible. Due to the shallow snowpack, releases will remain small-sized.

The snowpack is unfavourable over widespread areas and still shallow or has even receded to the the higher temperatures. On high alpine shady slopes the layering is often a sequence of melt-freeze crusts and faceted crystals inside the fundament, in places with blanketed surface hoar. This applies particularly to wind-protected terrain. Due to milder temperatures the snowpack is wet up to intermediate altitudes. The snow thereby forfeits is firmness and is set into motion on extremely steep slopes as small loose-snow avalanches. On Tuesday night a melt-freeze crust formed in some places. Older snowdrift accumulations have settled in the higher temperatures, the trigger-sensitivity has receded.

Thursday: in the Tauern and Lungau mostly dry, with scattered clouds and good visibility. Winds in high alpine regions will be strong from the west. In inneralpine regions winds at low and intermediate altitudes will be far lighter. At 2000 m: 0 degrees, at 3000 m, -6 degrees. Friday: heavy cloud with intermittent rainfall and - above 2000 m - snowfall. Poor visibilitiy, strong westerly winds. At 2000 m: 2 degrees; at 3000 m: -6 degrees.

No significant change is anticipated.