Wind slab
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Avoid fresh snowdrifts
Avoid fresh snowdrifts
Avalanche danger above the treeline is considerable, below that altitude danger is moderate. Main problem: snowdrifts. Above the timberline fresh snowdrift accumulations, esp. on N/E/S facing slopes are prone to triggering. Avalanches can be triggered by 1 person in many places and reach medium size. Danger zones increase with ascending altitude. Above 2500 m, weak layers in the old snowpack can be triggered. Danger zones esp. on shady very steep slopes. Transitions from shallow to deeper snow are unfavourable. Releases usually require large additional loading but can fracture down to deeper layers and then grow to large size. Below 2200 m the gliding snow activity persists. Danger zones occur in all aspects. Glide-snow avalanches can release on steep grassy slopes and smooth rocky ground at any time of day and reach medium size. Avoid zones below glide cracks.
Due to the winds the fresh snow has been and will continue to be transported. Above the treeline a wind crust will form. Soft layers beneath it constitute a weak layer. In high alpine region above 2500 m the snowpack base still consists of crusts with soft embedded layers. Elsewhere the old snow base is very compact, even the crusts near ground level are well bonded. Since the snowpack is thoroughly wet at low/intermediate altitudes the entire snowpack can glide over smooth ground (grass, rocks) if the gradient is steep enough.
The day in the Northern Alps will begin with heavy cloud cover, reduced visibility, possibly a small amount of snowfall. Along the Tauern, frequent sunshine which will dominate in the northern regions. Visibility will then improve noticeably. Winds will be mostly light to moderate from the west (30 km/hr). Along the Tauern, stormy NW gusts can reach 70 km/hr, but will slacken off. Mild air masses will move in from the west. At 2000 m temperatures will rise from -7 to -4 degrees, at 3000 m from -10 to -5 degrees.
As a result of higher temperatures the snowdrift problem will recede. The gliding snow problem will persist.
Bulletin data: Avalanche Warning Service Salzburg (CC BY 4.0)