Snow conditions 27.11.2017

General danger level - Monday, 27 November 2017

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

Main problem: new snow

Danger pattern: Cold weather, poorly bonded fresh snow with wind



Risk assessment

Avalanche danger is mainly in the Kamnik-Savinja Alps and eastern Karawanks above about 1500 m elevation, elsewhere above about 1700 m CONSIDERABLE, 3rd degree, lower down MODERATE, 2nd degree. Steeper slopes and places with wind-blown snow are dangerous, where even with minor snow cover loading you can trigger an avalanche. Spontaneous avalanches from steep slopes are also expected. In elevations where it initially rained, the connection between the old snowpack and new snow is much better, so avalanche danger is lower there. Steeper slopes and grassy slopes in the mid-mountains that were bare before snowfall are more dangerous.



Snow conditions

During the night to Sunday, precipitation was abundant. Initially it rained up to about 1800 m elevation, possibly higher in the west in places, then the snow line quickly dropped to the lowlands. More precipitation fell as snow especially in the eastern part of our mountains, in the west below the snow line quite a lot of rain as well. In the high mountains 30 to about 60 cm of snow fell, lower down 20 to about 30 cm, below about 800 m elevation even less. The snowpack reaches mostly to about 600 m elevation, in the west in places even higher. New snow is especially in the high mountains poorly bonded to mostly crusty base. Due to low temperatures even slight wind transported it into drifts, so there is a lot of wind-blown snow. Avalanches started sliding from steep slopes soon after snowfall.



Forecast weather development

Today mostly clear and cold. Especially in the morning moderate northerly wind will blow, in the afternoon it will weaken and be somewhat stronger only on higher summits. On Tuesday after a clear start it will cloud over during the day. Freezing level at about 900 m elevation, on Pohorje and in eastern Karawanks even above 1500 m. Southwesterly wind will strengthen. In the night to Tuesday precipitation will start appearing in the west, on Wednesday during the day covering most of Slovenia. Snow line initially to lowlands in many places, on Wednesday during the day it may temporarily rise to about 800 m elevation. It will be higher in the south and northeast of the country.



Tendency of snow conditions

Today new snow will settle only slowly. Northerly wind will transport it into drifts on southern sides of ridges and settle. Tomorrow due to slight warming it will settle somewhat more in the mid-mountains, southwesterly wind will create new drifts on eastern slopes. Due to clouding and consequently higher air humidity, snow will transform a bit faster in the afternoon and night to Wednesday, at the same time new snowing on soft base, so the connection between new snow and existing snowpack will presumably be relatively good. Quite a lot of new snow is expected, this time more in the area of the Julian Alps and western Karawanks, as well as in the Snežnik area, where the snow line will remain below 1000 m elevation or even lower this time. Spontaneous triggering mainly of poorly bonded dry snow avalanches from steep slopes is expected.



Next bulletin: Wednesday, 29 November 2017



Source: ARSO