Snow conditions 28.3.2018

General danger level - Wednesday, 28. 3. 2018

The danger is level 2 on the European five-level scale - MODERATE.

Main problem: weak layers, wet snow

Danger pattern: Spring situation



Risk assessment

The avalanche danger is above sea level around 1300 m mostly MODERATE, level 2. Lower down it is LOW, level 1, due to smaller amounts of snow and already more transformed snow. The main problem remains the weak bond between the old hard layer and larger amounts of newer poorly bonded snow. New layers, especially in wind slabs, are potentially unstable. In mid-day and afternoon, snow on sun-exposed slopes becomes somewhat more labile. Steep slopes and areas with wind-blown snow are particularly dangerous. There, with greater load on the snowpack, you can trigger an avalanche. The probability of spontaneous avalanching increases slightly during the day on sun-exposed slopes especially below around 1500 m above sea level.



Snow conditions

The snowpack is mostly soft or refrozen in shaded locations. Elsewhere it is crusty, scoured on wind-exposed locations. Conditions change rapidly locally. On sun-exposed locations snow softens during the day, refreezes at night. There is much wind slab.



Forecast weather development

Today there will be fairly sunny weather, a strengthened southwesterly will blow. Tomorrow cloudy. In the morning precipitation mainly in the western part of our mountains, in the afternoon or evening it will spread eastward. The snow line will mostly be between 1300 and 1500 m. On Friday precipitation will temporarily weaken and temporarily cease in the east, but especially in Posočje it will still be of moderate intensity. The snow line will fluctuate somewhat. On Saturday precipitation will spread eastward again, in the night to Sunday the snow line may drop below 1000 m as well.



Tendency of snow conditions

Avalanche conditions will change rapidly from tomorrow on. ABOVE the snow line the snowpack will thicken. Wind will form wind slabs. By Friday morning around 20 to about 50 cm of snow is forecast in the Julian Alps and western Karawanks, further east up to about 20 cm. Higher it will snow on mostly crusty base, thus weak layer under new snow. Lower the snow will be wet and bond better to the base. From steep slopes poorly bonded snow avalanches may release, due to wind-blown snow the snowpack will again be conditionally more unstable. BELOW the snow line rain will soak the old snowpack, thus slab avalanches may release from steep slopes. Lower, where there is now little snow, the danger will therefore be smaller.



Next issue: Friday, 30. 3. 2018



Source: ARSO