Snow conditions 13.1.2021

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

Main problem: wind slab, weak layers



Risk assessment

Avalanche danger is above about 1400 m altitude CONSIDERABLE, 3rd degree, lower down MODERATE, 2nd degree. In the eastern part of our mountains, where there is less snow, the boundary between 2nd and 3rd degree is somewhat higher. Steeper slopes and numerous spots with wind-blown snow and gullies where snow has accumulated are especially dangerous. There, even with minor loading you can trigger slab avalanches from steep slopes. On steep slopes, individual spontaneous slab avalanches are possible due to overloading from wind-blown snow.



Snow conditions

The snowpack began to change on Tuesday. Below about 1500 m, with transient warming, snow on pronounced north-facing slopes softened somewhat and then froze, forming crust. On wind-exposed spots, yesterday moderate winds, strong in high mountains from the north, transported light snow and formed new deposits, cornices and slabs, now also starting on southern and eastern slopes. Wind slab is now present on numerous slopes. Already in previous days slab avalanches occurred with minor loading, and this danger has now increased. The snowpack remains soft and deeply collapsible in sheltered spots, but in high mountains the strong wind influence is evident. Overall, due to cold weather the snowpack has not transformed much and remains potentially unstable. Weak layers are present in the snowpack, conditions are demanding especially in high mountains.



Forecast weather development

This morning initially some medium cloudiness, during the day mostly clear. Moderate to strong northwesterly wind in high mountains. Cooling. Midday temperature at 1500 m around -6, at 2500 m around -13 °C. Thursday morning initially mostly cloudy or foggy, locally snow showers. Up to 5 cm dry snow. During the day mostly clear. Moderate to strong northwesterly wind in high mountains. Midday temperature at 1500 m around -7, at 2500 m around -14 °C. Friday mostly clear, wind weakening. Still cold, at 1500 m around -6, at 2500 m -12 °C. Saturday increasing cloudiness especially in eastern mountain groups. Weak to moderate northerly wind. Even colder.



Trend in snow conditions

Due to cold weather, the snowpack will not stabilize in coming days. Strong winds will form thicker and more extensive slabs especially on southern and eastern sides of ridges and passes. Individual spontaneous slab avalanches possible. Icy patches will increase. During calmer periods, the snow surface will cool more, potentially weakening layer bonding especially in sheltered and shady areas. Avalanche danger will remain CONSIDERABLE, 3rd degree above about 1400 m, mostly MODERATE 2nd degree lower down.



Next bulletin: Friday, 15.1.2021



Source: ARSO