More Alpine avalanches to come?

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  • A mountainside with a small loose avalanche. Image: Nicolas Vigier

    Map of predicted snowfall (cm/24 hours) across Europe on Saturday. Image: MeteoGroup

    Map of predicted snowfall (cm/24 hours) across Europe on Sunday. Image: MeteoGroup

  • More Alpine avalanches to come?
    14.01.2016 14:40

    Alpine ski resorts have experienced plenty of welcome snowfall over the last couple of weeks. After a slow start to the season with an area of high pressure bringing dry and mild weather in December, the past two weeks have seen colder conditions with fronts bringing bands of snow. However, the recent heavy snowfall and fluctuating temperatures have caused an un-welcome side-effect; avalanches.

    An avalanche is a rapid fall of snow and debris down a hill or mountainside and these tend to occur most frequently through the ski season, from December to April.

    There are different types of avalanches too with most falling into either a ‘loose’ or ‘slab’ category. Loose avalanches involve loose, unconsolidated snow. A slab avalanche involves a block of snow that fractures from the snowpack and slides down the slope. A slab avalanche can be thought of as a layer of snow sliding down a car windscreen as the temperature starts to rises. Slab avalanches tend to be more serious than the loose category, and are capable of a lot of damage if the block of snow involved is very large.

    There are many factors that can contribute to the cause of an avalanche but recent heavy snowfall significantly increases the risk, particularly if there is a layer of ice underneath the fresh snow or if the temperature rises after the snowfall. Indeed, the recent heavy snowfall would likely have contributed to the avalanches over the French and Italian Alps that have been making the news.

    Through this weekend, the Alps is likely to see further snowfall as frigid arctic winds sweep southwards across much of Europe. The heaviest falls are likely to be over French and Swiss Alps with another 20-30cm falling there and significantly more for the highest slopes. Therefore, some areas are likely to continue having a moderate to high risk of avalanches through the coming days.

    Early next week, an area of high pressure toppling in from the north-west will bring a change in conditions to the Alps. It will become drier, calmer and colder. The avalanche risk is likely to decrease somewhat as the fresh snowfall gets some time to become more consolidated. It will become brighter too, giving more pleasant skiing conditions.

    Meanwhile, back in the UK, this weekend will be dry and sunny for many albeit cold and frosty with temperatures plummeting well below freezing by night. There will be reasonable skiing conditions for some of the Scottish resorts too with a few snow flurries likely before this weekend.

    By: Paul Mott