Snow conditions 8.12.2017

General avalanche danger level - Friday, 8 December 2017

The danger is level 2 on the European 5-level scale - MODERATE.

Main problem: wind slab, new snow, wet snow

Danger pattern: Cold weather, poorly bonded fresh snow due to wind

Danger pattern: Cooling after warm weather / warming after cold



Risk assessment

Avalanche danger is currently above about 1200 m elevation MODERATE, level 2, and lower down LOW, level 1. Steep slopes and areas with wind slab are dangerous, where with greater load on the snowpack you can trigger an avalanche. No spontaneous avalanching is expected. BUT CONDITIONS ARE CHANGING RAPIDLY!



Snowpack

The snowpack has settled and stabilized somewhat due to warming at altitude in recent days, mainly on sun-exposed aspects a crust has formed that does not support human weight. In shaded areas the snow has remained dry and soft. There is a lot of sastrugi. Ridges are heavily wind-scoured.



Forecast weather evolution

Today cloudy. Precipitation will intensify in the west and by evening from the west cover all of Slovenia. Snow line mostly between 1000 and 1200 m above sea level. Strong southwest wind blowing. In the evening the snow line will start to lower and overnight will drop to the lowlands. Strong northerly wind will blow. Snowfall will end everywhere by Saturday morning, in the afternoon clearing from the northwest. Sunday initially mostly clear with a cold morning. During the day clouding from the west. In the afternoon precipitation will start in the west. Initially the snow line will be low, overnight to Monday it will rise and on Monday it will be around 1800 m above sea level or even higher. Strong southwest wind blowing, very strong in the mountains.



Tendency of snow conditions

Today initially below 1200 m the snowpack will melt and soften, higher up it will snow. By tomorrow morning 10 to about 30 cm of snow will fall, most in the high mountains of northwestern Slovenia and on Snežnik. The snow will likely bond poorly to the base above about 1200 m, as it will snow on crust in places, and the snow will be dry. Dry slab avalanches of poorly bonded snow may release from steep slopes. Lower down, where it will initially rain, the snowpack will get wet and individual full-depth wet snow avalanches may release, then initially wet snow will fall, so the bond between old and new snow will be better. Strong northerly wind will form wind slabs. Avalanche danger will INCREASE. On Sunday the southwest wind will strengthen, forming wind slabs on northern and eastern sides of ridges and saddles. In the afternoon low-level snow in western half of Slovenia, overnight to Monday the snow line will rise. Below about 1800 m rain will wet the snowpack again and it will become unstable, higher up snow on soft base, so no new weak layer in the snowpack is expected. By Monday morning little precipitation in the eastern part of our mountains, most again in western Slovenia. Above about 1800 to 2000 m up to more than 30 cm of snow possible by morning. RISK OF AVALANCHES WILL INCREASE.



Next bulletin: Monday, 11 December 2017



Source: ARSO