Snow conditions 13.12.2021

General danger level - Monday, 13 December 2021
The danger is level 3 on the European five-level scale - CONSIDERABLE.
Main problem: wind-blown snow, wet snow
Danger pattern: cooling after warm weather / warming after cold

Risk assessment
The avalanche danger is mainly above the treeline CONSIDERABLE, level 3, and lower down even below 1000 m MODERATE, level 2. Particularly dangerous spots with fresh wind-blown snow, mainly on south-facing slopes above the treeline. Snow has covered old weak layers, making the danger hard to recognize. Especially where there is less new snow, you can trigger a slab avalanche even with a small load. With warming today and in the coming days, we also expect spontaneous releases of wetter snow. This applies especially to sunny grassy slopes below about 1600 m, individual weak layers may also fail. We expect snow avalanches on steep slopes also in the prealpine area; in northern Primorska, Škofjeloško and Polhograjsko hribovje, and Zasavje.

Snow conditions
At the end of the week, it was quite sunny in the mountains, with strong northerly winds in many places. The wind was drifting snow on exposed spots and building snow drifts, cornices and slabs, mainly on southern slopes. In the high mountains, on ridges the wind scoured snow down to the hard base, in places even to bare ground. In more sheltered spots, due to slightly warmer weather, the transformation process of the snowpack proceeded faster, bonding better with older layers. Snow conditions are mixed. There is still quite a bit of fresh snow, and due to wind and sun, a crust has started to form. With pronounced warming today during the day, the snow will especially in sunny spots in mid-mountains and lower hills become wet and start transforming faster, in the high mountains this process will be slower.

Forecast weather development
Today it will be moderately to mostly cloudy, especially in the eastern part of our mountains the summits will be in clouds. In the morning, occasional light precipitation possible in eastern Karavanke and on Pohorje. Some sun in the afternoon in hills of western Slovenia. Moderate northerly wind blowing, somewhat stronger in the eastern part of our mountains. Warmer than in previous days. In the Julian Alps area at 1500 m around 4, at 2500 m around -2 °C. Towards the east, temperatures lower, on Pohorje at 1500 m around 0 °C. Tomorrow mostly clear, midday and afternoon more dense high cloudiness. Only occasionally in the east moderately to mostly cloudy, some summits of eastern Karavanke and Pohorje may be in clouds. Weak to moderate northerly wind. Temperature at 1500 m in the Julian Alps area around 5, at 2500 m around -1 °C. Towards the east lower temperatures, on Pohorje at 1500 m around 2 °C. On Wednesday more low cloudiness covering mainly mid-mountains, more clear in high mountains and in the area of western Julian Alps. Cooler, especially in mid-mountains. Still moderate northeasterly wind. Dry weather will most likely continue until the end of the week.

Trend in snow conditions
In the coming days, the snowpack on sun-exposed aspects will get wet during the day and refreeze at night, crust will strengthen. In shady spots, warming due to dry air will not be so noticeable. In the high mountains, northerly wind will occasionally still transport snow and build deposits. Especially on southern grassy slopes in the coming days during the day, we still expect full-depth wet snow avalanches. Steep gullies with lots of wind-blown snow poorly bonded to the base will also be dangerous. Even above 2000 m, due to warming, some weak layer on sun-exposed slopes may fail. In the high mountains, spots with wind-blown snow will remain dangerous. We expect the avalanche danger to decrease in the second half of the week. On ridges, the risk of slips will increase. When going to the mountains, choose avalanche-safe terrain. EVEN FULL SAFETY GEAR WILL NOT PROTECT YOU FROM AN AVALANCHE if you do not choose safe routes on your way. The next avalanche bulletin will be published on Wednesday, 15.12.2021.

Next issue: Wednesday, 15 December 2021

Source: ARSO