Snow conditions 21.4.2023

General avalanche danger level - Friday, 21 April 2023
Danger is 3rd degree on the European five-level scale - CONSIDERABLE.
Main problem: wind slab, wet snow
Danger pattern: Spring situation

Risk assessment
Avalanche danger in the high mountains above about 1800 m a.s.l. is CONSIDERABLE (significant), 3rd degree, below about 1800 m currently LOW, 1st degree, but during the day with daytime thaw it will increase and be MODERATE, 2nd degree. With increasingly warmer weather, spontaneous southern snow avalanches are occurring. Glide avalanches are possible on steep grassy slopes. In the higher high mountains there are still areas of wind slab now covered by new snow, so the danger is hard to recognise. Even with minor loading you can trigger a slab snow avalanche. With lower elevation the danger of triggering decreases rapidly. Greater attention is needed especially in gullies and under cliffs, where avalanches can reach lower.

Snow conditions
On Friday cloudy and foggy weather continues, wind is light. Light precipitation is occurring. It has warmed slightly since yesterday. The 0 °C isotherm is currently at about 2000 m a.s.l. In the high mountains of the Julian Alps 10 to 20 cm of snow fell yesterday and overnight today, in the mid-mountains up to 5 cm, elsewhere significantly less precipitation. It snowed with light wind, so there are not many new snow drifts. The snowpack in the high mountains is dry and crusty, snow depth is uneven. In the mid-mountains there are more and more bare patches.

Forecast weather development
On Friday variable to mostly cloudy, summits occasionally in clouds. Local showers will occur, more frequent midday and afternoon. Snow line at about 1700 m a.s.l., with heavier precipitation it may drop lower. Light southeasterly wind. Temperature at 1500 m around 4, at 2500 m around -3 °C. On Saturday partly clear, low cloud possible in the mid-mountains of the Kamnik-Savinja Alps in the morning and forenoon. During the day some variable cumulus clouds will form. Light westerly wind. Even warmer. The 0 °C isotherm will rise above 2500 m a.s.l. during the day. On Sunday variable to mostly cloudy and occasionally foggy. Light precipitation, partly showers, will start late afternoon and evening. Snow only in high mountains. Light to moderate westerly wind. Temperature at 1500 m around 6, at 2500 m around 0 °C. On Monday and Tuesday two weather disturbances will arrive. Amount of precipitation still uncertain, snow in high mountains, initially rain in mid-mountains. After front passage, especially on Tuesday, strong northerly wind.

Trend in snow conditions
Due to gradual thaw and more sunshine, avalanche triggering danger will not yet decrease. In high mountains (on Saturday) CONSIDERABLE (or significant), 3rd degree, below 1800 m initially LOW, 1st degree, increasing during the day. Main danger will be wet snow avalanches and in high mountains also slab snow avalanches. Conditions remain demanding, considerable caution needed when choosing safe route. On Sunday triggering danger will slightly decrease due to more cloudy weather. With new snowfall on Monday and Tuesday in high mountains expect renewed increase in danger.

Next issue: Tuesday, 25 April 2023

Source: ARSO