Mürzsteg Alps

Storm-strength winds, poor visibility, widespread snowdrift accumulations at high altitudes.

Storm-strength winds, poor visibility, widespread snowdrift accumulations at high altitudes.

Moderate avalanche danger prevails above the treeline, due to freshly formed snowdrifts. Danger zones are mainly on east-facing and south-facing slopes, particularly behind ridgelines and protruberances in the terrain and at entries into gullies and bowls, in places triggerable by minimum additional loading. Poor visibility in outlying terrain makes recognition of the danger zones much more difficult. Below the treeline, avalanche danger is minor as a consequence of little snow on the ground and not much wind impact.

Prior to the onset of winter on Friday, there was a cohesive area-wide snowpack only above about 1500 m. This snowpack fundament is marked by intermittent phases of higher temperatures and rainfall, making it moist at intermediate altitudes and melt-freeze encrusted, or at least riddled with such crusts, at high altitudes. Surface hoar was formed on the surface in many places during the night of clear skies on Thursday. Atop this fundament, fresh snow will be deposited on Friday accompanied by storm-strength NW winds, which in turn will lead to wide-ranging snowdrift accumulations on east-facing and south-facing slopes. The expected amounts of fresh snow by Saturday will reach 30 cm. By Sunday morning, an additional 20 cm of fresh snow will be added. Both inside the fresh snowdrifts (loosely-packed fresh snow, generated in wind intermissions) and in the transitions to the old snow (surface hoar), weak layers can be expected.

On Saturday, heavy clouds from the north will lodge in the barrier zones of the Northern Alps and the Main Alpine Ridge, snowfall will continue down to low lying areas. Winds will be blowing at storm strength from the northwest. Temperatures at 2000 will lie at wintery -12 degrees, and feel even colder due to wind impact. Visibility will be severely impaired. Also on Sunday it will remain stormy and cold, though the snowfall will slacken off. Monday will be without precipitation by and large, and temperatures will rise.

Further snowfall and stormy NW winds on Saturday and on Saturday night will reinforce the problem of snowdrift accumulations.