Snow conditions 30.1.2023

General danger level - Monday, 30 January 2023
Danger is level 3 on the European five-level scale - CONSIDERABLE.
Main problem: wind-drifted snow
Danger pattern: Cooling after warm weather / warming after cold weather

Risk assessment
Avalanche danger above about 1600 m is CONSIDERABLE (or significant), level 3, lower down MODERATE, level 2. Steeper slopes above the forest line are particularly dangerous, where there are extensive areas of wind-drifted snow, mainly on southern and western aspects. There, even a small load can trigger slab avalanches. In the old snowpack, now buried under a thick blanket of new snow, there are weak layers, especially on shady slopes, which may fail at individual spots under additional load. This can happen especially where there is less snow due to wind influence. Below about 1600 m, steep grassy slopes are mainly dangerous. Snow and avalanche conditions in the high mountains are very demanding.

Snow conditions
It has warmed up slightly in the mountains, above about 800 m a.s.l. a layer of air several hundred meters thick with temperatures slightly above zero has formed, so the snow surface has become a bit crusty on sunny aspects. Except for pronounced sunny mid-mountain and lower hill slopes, the snow is mostly soft and loose, with crusts formed by wind in places. Above the forest line, there are many areas with wind-drifted snow, ridges are scoured to hard base. There are many slabs and crusts. The snowpack has generally stabilised somewhat. Due to the cold, not many avalanches have been released. Snowpack transformation is much slower in higher areas. At the same time, a moderate to strong northeast wind has been blowing mainly in the high mountains, transporting snow and building snow drifts at exposed spots.

Forecast weather development
Today, Monday, partly clear. Mostly light west to northwest wind. Temperature at 1500 m around midday from -2 to 2, at 2500 m around -3 °C. Tuesday mostly clear, moderate to strong northerly wind. It will cool down and temperatures will be below zero everywhere in the mountains again. Wednesday partly clear with occasional moderate cloudiness. Light, occasionally moderate west to northwest wind. Warming up again, zero isotherm around 1500 m a.s.l. Thursday moderately cloudy, occasionally mostly cloudy especially in the northeast and mostly dry. Cooling in the afternoon. Northwest wind strengthening.

Trend in snow conditions
Today, Monday afternoon, due to slight warming especially on sunny mid-mountain slopes, somewhat increased avalanche activity is expected. Individual slabs may release, individual ground (glide) avalanches may occur. Steep grassy slopes and gullies will be particularly dangerous. Danger will also be increased in the pre-alpine region (northern Primorska, Polhograjsko and Škofjeloško hribovje, Posavsko hribovje and similar), in short everywhere where it is steep enough, there is plenty of snow and it is poorly transformed now. On Tuesday, the snowpack will stabilise somewhat with cooling, on Wednesday and Thursday the possibility of spontaneous avalanching will increase again somewhat, greater chance mainly on sunny slopes midday and early afternoon.

Next issue: Thursday, 2 February 2023

Source: ARSO