Snow conditions 11.12.2023

General avalanche danger level - Monday, 11 December 2023
Danger is level 2 on the European five-level scale - MODERATE.
Main problem: wind slab, new snow
Danger pattern: Cooling after warm weather / warming after cold

Risk assessment
Avalanche danger above about 1800 m is MODERATE, level 2, lower down LOW, level 1. Steep slopes and areas with wind slab are particularly dangerous, where smaller or medium-sized slab avalanches can be triggered with little additional load. Wind-exposed locations are heavily scoured and icy in places, icy patches also occur in the mid-mountain range where there is little snow. There is a risk of slipping there.

Snow conditions
There is little snow, more only in the high mountains, above about 2000 m the snowpack thickness increases rapidly. In recent days, especially in the mid-mountains, it has settled somewhat, due to daily thaws a crust has formed, only in shaded locations the snow has remained mostly dry. In the high mountains, the snowpack condition is quite varied. In sheltered locations it is mostly soft, otherwise there is a crust on the surface, mainly due to wind influence. Wind-exposed locations are scoured, icy in places, in leeward locations there are slabs.

Forecast weather development
Today it will be partly clear at first, cloudiness will increase in the afternoon, foggy in places. During the day there will be minor, local precipitation. The zero isotherm will be above 2500 m above sea level. A moderate to strong westerly to southwesterly wind will blow, weakening towards evening and turning northwesterly. Tomorrow it will be mostly clear at first, clouding over towards noon, foggy in the evening. Minor precipitation will appear in the hills of western Slovenia towards evening. A weak southwesterly wind will blow, strengthening towards evening. On Wednesday it will be cloudy and foggy with precipitation, more frequent and intense in the southern half of Slovenia. The snow line will be around 2000 m in the morning. During the day it will descend, in the mountains with the main precipitation between 800 and 1200 m. A moderate southwesterly will blow, weakening in the afternoon and beginning to turn northeasterly towards evening. We expect 10 to 30 cm of new snow, which in the high mountains will first be transported by the southwesterly, later by the northeasterly, which will strengthen on Thursday during the day. On Thursday and Friday it will be dry and noticeably colder, with a moderate to strong northerly wind.

Trend in snow conditions
Avalanche danger will not change today and tomorrow, nor will snow conditions much. Due to thawing, snow in the high mountains may temporarily become somewhat wet and settle, individual slab avalanches may release from steep slopes. Also in gullies where snow is accumulated, the snowpack will be temporarily less stable. On Wednesday, new snow will change snow and avalanche conditions, but we do not expect the danger to increase significantly. New snow will cover old snow deposits, new deposits will first form on northern and eastern sides of ridges and saddles, then on southern and western. Lower down, new snow will bond well to the base, above about 1800 m less so. We do not expect much spontaneous avalanching from Wednesday onwards, but avalanche conditions will be more demanding due to new slabs and covered old ones. With cooling and windy weather from Thursday onwards, snow will remain dry and soft and poorly transformed. Ridges will be scoured and icy or hard.

Next issue: Thursday, 14 December 2023

Source: ARSO