Goldberg Group Central

Increased trigger-sensitivity of snowdrifts, esp.at high altitudes

Increased trigger-sensitivity of snowdrifts, esp.at high altitudes

Danger of avalanches above about 2300 m is CONSIDERABLE, below that altitude to the treeline MODERATE. On very steep slopes below 2400 m, naturally triggered glide-snow avalanches are possible. Above the timberline slab avalanches can trigger. Avalanche prone locations focus on gullies in all aspects and wind-loaded steep slope and fresh snowdrifts in E/S aspects. Triggering a small-to-medium sized slab avalanche is possible there even by minimum additional loading. At high altitudes, slab avalanches can in isolated cases grow to large size.

Warmth, rainfall and subsequent nocturnal cooling have helped the snowpack to regain firmness at high altitudes. The moistened snowpack has a melt-freeze crust on the surface. Drizzle up to 2700 m on Monday has left a thin ice crust behind. The snowpack is gliding over smooth, grass-covered slopes below 2400 m. Above the timberline there are older drifts deposited in gullies and bowls which are blanketed by snow, in high alpine regions shallow drifts generated by northerly winds. In higher, wind-protected zones the loose snow can become a weak layer for the slightly-bonded new snow which is deposited on top of it. In high alpine regions, particularly on shady slopes above 2200 m, weak, soft layers of faceted crystals are evident in the snowpack fundament.

On Thursday, visibility above the valley fog will initially be adequate, with sunshine. In the afternoon heavy cloud cover will move in from the north, which will also impede visibility. Winds in the Tauern will be brisk to strong from the north. At 3000 m: -5 degrees; at 1500 m: +1 degree. On Friday, little change, generally adequate visibility above the high fog. Winds on the Tauern Main Ridge will become increasingly stormy from the northwest. At 3000 m: -4 degrees; at 1500m: +2 degrees.

Little change on Friday. Fresh drifts on the Main Tauern Ridge during the course of the day due to northerly winds.