Snow conditions 26.3.2018

General danger level - Monday, 26. 3. 2018

Danger is level 3 on the European five-level scale - CONSIDERABLE.

Main problem: weak layers

Danger pattern: Spring situation

Danger pattern: Cooling after warm weather / warming after frost



Risk assessment

Avalanche danger above sea level around 1500 m is mostly CONSIDERABLE, level 3. Lower down due to smaller snow amounts and already more metamorphosed snow the danger is MODERATE, level 2. The main problem remains the weak connection between the old hard layer and larger amounts of newer unsettled snow. New layers, especially wind slabs, are also very brittle due to the cold. Especially dangerous are steep slopes and areas with drifted snow. There you can trigger an avalanche already with minor snow cover loading. The probability for spontaneous slab release increases slightly during the day on sun-exposed slopes especially in the mid-mountains.



Snow conditions

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



Forecast weather development

Dry and relatively cold weather continues. Today it warmed slightly, above zero up to sea level around 1600 m, lower a layer of colder air remains. Tomorrow variably cloudy, less sun than today and especially in the afternoon short-term minor snow showers will form. Wednesday moderately, occasionally mostly cloudy. Strong southwesterly will blow. Even warmer. Thursday cloudy with precipitation. Snow line initially around 1400 m, but will drop to around 1000 m above sea level.



Trend in snow conditions

Conditions will remain at least locally quite unfavourable. Due to slightly warmer air mass the influence of daytime warming and nighttime freezing will increase. At night snow will refreeze, during the day it will soften, only in shaded high mountain locations snow will remain dry or refrozen. Especially on sun-exposed slopes the snowpack will destabilize during the day. Crust will strengthen. In the long term this weather will positively influence snowpack stabilization especially in the mid-mountains. But because there is much drifted snow and weak layers persist in the snowpack, this process will be lengthy. In high mountain gullies the possibility remains to trigger wind slab and still unprocessed snow on steeper slopes already with minor loading. Locally on sun-exposed slopes cracks exist which during daytime travel can be release areas for slab avalanches.



Next issue: Wednesday, 28. 3. 2018



Source: ARSO