Goldberg Group Central

Critical avalanche situation: naturally triggered avalanches expected

Critical avalanche situation: naturally triggered avalanches expected

Avalanche danger above 2200m is HIGH, below that altitude danger is considerable. The situation is dangerous for winter sports enthusiasts, slab avalanches can be triggered by minimum additional loading and grow to medium size, also isolated naturally triggered avalanches from ridgeline snowdrifts are possible. Near-surface slab avalanches in fresh snow and drifts can fracture down to deeper layers above 2200m on W/N/E-facing slopes and grow to large size. Due to solar radiation in afternoon hours, naturally triggered loose-snow avalanches can be expected. Avalanches released at higher altitudes can fracture down to deeper layers and then plummet down to green zones. Especially above the timberline, small-to-medium glide-snow avalanches can trigger naturally in very steep grass-covered terrain.

Since Friday evening 50-100cm of fresh snow has been registered at high altitudes. By Tuesday midday another 20-30cm is anticpated. Inside the fresh snow and snowdrifts there are soft layers of loose snow or graupel. In the lower and middle parts of the snowpack above 2200m there are weak layers of faceted crystals which are embedded between cdrusts. Below 2000m the old snow is moist.

During the nocturnal hours, moist/cold air masses from the north will move over the Alps, light-to-moderate snowfall can be expected, intensifying in the latter part of the night. In exposed high-altitude terrain, strong-velocity northerly winds will prevail. On Tuesday, intermittent snowfall, in high-altitude Tauern regions a strong northerly wind will be blowing reaching 60 km/hr in exposed terrain. In the Northern Alps, moderate N/NE winds will prevail, windspeeds of 30 km/hr. At 2000m: -5 degrees; at 3000m: -10 degrees.

As the snow settles the trigger-sensitivity of weak layers of fresh snow and drifts will gradually diminish