Lower Tauern South

Caution urged towards weak old snow: considerable avalanche danger above timberline

Caution urged towards weak old snow: considerable avalanche danger above timberline

Weak layers inside the old snowpack are the main danger. Avalanche prone locations are found in all aspects above the treeline, particularly on steep, relatively wind-protected shady slopes. Ridgeline gullies and bowls are especially treacherous. Danger zones cannot be recognized. Avalanches can be triggered even by one single skier and attain medium size. Alarm signals such as 'whumpf' noises and glide-cracks are possible indicators of imminent danger. Remote triggerings and naturally triggered avalanches are possible particularly in areas where snowfall has been heaviest. In addition, as a result of moderate to strong northerly winds, fresh trigger-sensitive snowdrift accumulations have been formed behind abrupt discontinuities in the terrain and in ridgelines in NE-E-S aspects. In the major areas of precipitation, these can grow to dangerously large size. South of the Main Alpine Ridge, danger zones are found in all aspects as a result of strong northerly winds. Snowdrift accumulations should be avoided whenever possible.

The snow depths range from 40 to 90 cm. By Sunday midday, anothern 15-20 cm of fresh snow is anticipated, more from place to place. Particularly on shady slopes the snowpack layering is currently unfavourable. Generally in the lower part of the (still shallow) snow cover there is a sequence of melt-freeze crusts and faceted crystals which, depending on altitude, have formed over recent weeks and months. Atop of that in wind-protected zones above the treeline lie fresh and older snowdrift accumulations from recent weeks which were deposited on top of the expansively metamorphosed (faceted) layers and are still prone to triggering. The fresh snow blankets these older layers of the snowpack. Also in some wind-protected areas there is surface hoar evident on the snowpack, providing another potential weak layer which is blanketed by fresh fallen snow. Amid moderate to strong NW winds, new snowdrift accumulations are being generated in wind-protected, mostly ridgeline zones, behind abrupt discontinuities in the terrain and in bowls.

Sunday: the peaks will mostly be shrouded in clouds, intermittent snowfall, less in the afternoon. At higher altitudes, a NW wind will cause renewed snow transport. It will be very cold: -13 degrees at 2000 m, -19° at 3000 m. Winds will make the cold seem even greater. Monday: mostly sunshine in the Tauern and Nockberge, high-fog like clouds near the Northern Alps. At high altitudes, an icy cold NW wind with speeds reaching 40 km/hr will be blowing. At 2000 m: -13 degrees; at 3000 m: -20 degrees.

Avalanche danger levels will persist.