Snow conditions in the mountains 3.3.2017

General danger level - Friday, 3 March 2017

Danger is level 3 on the European five-level scale - CONSIDERABLE.

Main problem: weak layers, new snow

Danger pattern: Cooling after warm weather / warming after cold

Danger pattern: Slopes covered with snow



Risk assessment

Avalanche danger above sea level around 1300 m is CONSIDERABLE, level 3, below sea level around 1300 m MODERATE, level 2, in Kamnik-Savinja Alps and eastern Karawanks, where there is less snow, LOW, level 1. Especially dangerous are steep slopes and places with wind slab on all sides of ridges. There you can trigger a slab avalanche already with minor load. Spontaneous avalanching is no longer expected for the most part. Snow is quite wind-packed due to strong wind blowing during snowfall.



Snow conditions

In the snow cover under the top layer of newest snow there is in many places a layer of graupel, which means a potential sliding surface. The snow cover has already somewhat settled in partly sunny weather. Freezing level was mostly at sea level between 1300 and 1500 m, higher up snow transformed more only on sun-exposed aspects, in shade many places still powder remained. Many wind slabs, on wind-exposed aspects snow is in many places completely wind-packed to older base.



Forecast weather development

Today moderately to mostly cloudy, somewhat more sun in eastern part of our mountains. Weak to moderate southwesterly will blow. Tomorrow partly clear in eastern Karawanks, elsewhere in mountains mostly cloudy and foggy in places. Occasional precipitation in the morning and partly forenoon mainly in western Julian Alps, during the day gradually spreading to western and central Karawanks and Kamnik-Savinja Alps. Snowfall line mostly between 1200 and 1500 m, higher eastward. More precipitation in Julian Alps, where up to around 40 cm snow can fall in the west, elsewhere in Julian Alps and western Karawanks 10 to 20 cm, in remaining part of our mountains around 10 cm. Strengthened southerly to southwesterly wind will blow. In the night to Sunday precipitation will temporarily appear also in eastern Karawanks. Sunday and until Monday morning variable to mostly cloudy. Occasional smaller precipitation expected mainly in Julian Alps and hills of northern Primorska and Notranjska. Somewhat colder, snowfall line around 300 m lower than Saturday. Southwesterly wind will somewhat weaken.



Trend of snow conditions

Today snow cover will continue slowly settling and metamorphosing, in places with sunny weather also in high mountains, elsewhere only below around 1500 m. Higher and in shady aspects snow will remain poorly metamorphosed and mostly soft and dry. Tomorrow with new snowfall new snow will start accumulating again, which strengthened southwesterly wind will drift into wind slabs on northern and eastern sides of ridges and load them. Snow above around 1500 m mostly dry and will adhere poorly to base where surface is crusted or harder due to wind. On Sunday due to quite cloudy weather and somewhat lower temperatures newly fallen snow will mostly not settle much and stabilise. Snow cover will remain POTENTIALLY UNSTABLE mainly at places with wind slab, where you can trigger slab avalanche, on old slabs also new snow. In Julian Alps, where more snow will fall by end of week, spontaneous avalanching mainly from steep slopes expected.



Next issue: Monday, 6 March 2017



Source: ARSO