Snow conditions 20.12.2017

General danger level - Wednesday, 20. 12. 2017

Danger is 2nd degree on the European five-level scale - MODERATE.

Main problem: wind-drifted snow

Danger pattern: Cooling after warm weather / warming after frost



Risk assessment

Avalanche danger is currently above sea level around 1400 m MODERATE, 2nd degree, lower down LOW, 1st degree. Steep slopes and places with wind-drifted snow are dangerous, where you can trigger mainly slab avalanches, which can release already with minor load on the snowpack. Lower down the snowpack is mostly stable due to smaller amount of snow and intervening rain in the past days.



Snow conditions

Dry and cold weather continues. The snowpack is slowly settling and metamorphosing. In sheltered locations it is mostly soft, in wind-exposed locations quite wind-packed and also hard. Especially in mid-mountains there is a thin crust on the surface in places. There are many drifts and wind slabs, ridges and passes are scoured to the old base in places.



Forecast weather development

Dry and partly sunny weather will continue in the coming days. Temperature will be below zero today, tomorrow warmer air will start to flow in at altitudes and by evening the freezing level will be at sea level around 1900 m. A strong temperature turnaround will occur, presumably the layer of cold air from the ground will reach sea level around 700 m. On Friday it will be even warmer at altitudes, the layer of cold air at ground even thinner. Freezing level at sea level between 1200 and 1800 m. Warm air will be relatively dry.



Trend in snow conditions

The snowpack will slowly metamorphose in the coming days. With gradual warming the air will be quite dry, so snow will not get much wet during the day, but will metamorphose faster and on sun-facing slopes a thin crust will nevertheless form. The snowpack will still be potentially unstable on steep slopes and places with wind-drifted snow, of which there are plenty. Avalanche danger will remain MODERATE, 2nd degree.



Next issue: Friday, 22. 12. 2017



Source: ARSO