Avalanche.report

Saturday 21 December 2024

Published 20 Dec 2024, 17:00:00


Danger level

treeline
Avalanche Problem
Wind slab
Treeline
New snow


Up to highest altitudes, new snow is mostly deposited atop bare ground, in particular on the sunny side. The risk of taking a fall and being hurt is high.

Avalanche danger above the treeline is considerable, below that altitude danger is low. Main problem: snowdrifts. Snowdrifts can be triggered as medium-sized slab avalanches even by minimum additional loading. Avalanche prone locations are found in steep terrain adjacent to and distant from ridges in N/E/SW aspects as well as in wind-loaded gullies and bowls. Snowdrift accumulations are blanketed by loose new snow and difficult to detect Frequency and size of danger zones increase with ascending altitude. At high altitudes, avalanches can fracture down to weak layers embedded in the old snow. Due to sun-shine, small to medium-sized loose snow avalanches can trigger naturally in extremely steep terrain. In addition, potentially small glide snow avalanches on steep grass-covered slopes and in sparsely wooded deciduous forests.

Snowpack

In orographic barrier zones stormy northwesterly winds will transport up to 40 cm of new fallen snow. When precipitations will start ceasing the wind will abate. Therefore, snowdrifts are frequently loosely blanketed and difficult to detect. Weak layers that are prone to triggering (partly graupel) are embedded in the snowdrift accumulations. At intermediate altitudes the cold new fallen snow is often deposited atop bare, often wet, ground, in particular on south-facing slopes. Elsewhere it is mostly deposited atop a melt-freeze crust or thin ice crust covering a comparatively warm old snowpack. Faceted crystals can form. More deeply embedded in the snowpack there are also soft weak, expansively metamorphosed layers close to crusts at high altitudes.

Tendency

As of Sunday, avalanche danger will increase as a consequence of new snow and wind.


Danger level

treeline
Avalanche Problem
Wind slab
Treeline
New snow


Up to highest altitudes, new snow is mostly deposited atop bare ground, in particular on the sunny side. The risk of taking a fall and being hurt is high.

Avalanche danger above the treeline is moderate, below that altitude danger is low. Main problem: snowdrifts. Snowdrifts can be triggered as medium-sized slab avalanches even by minimum additional loading. Avalanche prone locations are found in steep terrain adjacent to and distant from ridges in N/E/SW aspects as well as in wind-loaded gullies and bowls. In addition, smaller loose snow avalanches can trigger naturally in extremely steep terrain as a result of solar radiation. Small glide snow avalanches are also still possible on steep smooth grass-covered slopes.

Snowpack

Stormy northwesterly wind will transport 10 cm to 30 cm of new snow. When precipitations will start ceasing the wind will abate. Therefore, snowdrifts are frequently loosely blanketed and difficult to detect. Weak layers that are prone to triggering (partly graupel) are embedded in the snowdrift accumulations. At intermediate altitudes the cold new fallen snow is often deposited atop bare, often wet, ground, in particular on south-facing slopes. Elsewhere it is mostly deposited atop a melt-freeze crust or thin ice crust covering a comparatively warm old snowpack. Faceted crystals can form. At high altitudes above 2000 m, isolated spatially-limited weak layers are embedded in the old snow.

Tendency