Snow conditions 23.12.2019

Danger is 4th degree on the European five-level scale - HIGH.

Main problem: wind slab

Danger pattern: Cooling after warm weather / warming after cold



Risk assessment

Avalanche danger is currently in the high mountains of the Julian Alps above about 1800 m HIGH; 4th degree, in the high mountains of the Karawanks and Kamnik-Savinja Alps above about 2000 m CONSIDERABLE, 3rd degree, lower down mostly LOW, 1st degree. Especially steeper, and also moderately steep slopes are dangerous, where above 1800 m fresh snow can avalanche, there are also many new slabs on all aspects due to variable wind direction. Wind slab can be triggered on steeper slopes already with minor snowpack loading, avalanches can also release spontaneously - numerous small, also medium-sized and individual large avalanches possible. Below about 1600 m it mostly rained, only at the end of precipitation it also snowed. Therefore there is little snow there, fresh snow is well bonded to the base and no avalanching expected. Less snow also in the eastern Karawanks.



Snow conditions

In the Julian Alps at the end of the week above about 1800 m 100 to more than 150 cm of snow fell, more in the western and central part and above 2000 m elevation. Elsewhere fresh snow from 20 to about 80 cm, less towards the east and below 2000 m elevation. Lower it mostly rained. The snowpack is soft and loose. Due to strong wind there are many winddrifts, which first formed with southerly wind, then with northerly winds. It snowed on a relatively shallow soft base, under which there is however a crust layer. Above about 1700 m the snow is dry, lower wet. In the high mountains due to the large amount of new snow movement is quite impeded.



Forecast weather development

Today moderately cloudy, occasionally at first still predominantly cloudy in places. Moderate to strong northwesterly wind will blow. The zero isotherm will be today and in the coming days at about 1600 m elevation. Tomorrow and the day after mostly clear, only occasionally some moderate cloudiness in places. Northwesterly wind will weaken tomorrow morning and strengthen again in the evening and night to Wednesday.



Trend of snow conditions

New snow is especially in the high mountains of the Julian Alps really a lot, also in the high mountains of the Kamnik-Savinja Alps and Karawanks quite a lot. Above about 1800 m the snow will remain dry. It will slowly settle and transform and the snowpack will become more stable. Due to wind new winddrifts will form mainly on southern and eastern sides of ridges and passes. Initially dry, unbonded snow avalanches and also slab avalanches will still release from steep slopes, but they will become less likely. However, the hidden danger will remain that you trigger a snow avalanche already with minor snowpack loading on sufficiently steep slopes with wind slab. Lower, where the temperature during the day will be above zero, the snow will settle faster and also melt, freeze at night and a crust will form. Avalanche danger will below about 1800 m mostly be low.



Next issue: Thursday, 26. 12. 2019



Source: ARSO