Northern Cairngorms

NC for 21.12 Storm force winds! Localised windslab building N,NE and E aspects above 1000m. Avalanche Hazard Moderate.

NC for 21.12 Storm force winds! Localised windslab building N,NE and E aspects above 1000m. Avalanche Hazard Moderate.

Forecast Snow Stability: Localised accumulations of windslab will build as the day progresses in steep wind sheltered North to East aspects above 1000 metres. Accumulations will contain weaknesses where they achieve depth, particularly in areas such as coire rims and headwalls. A light dusting of snow will overlie what is predominately bare ground above 600 metres, while slopes exposed to the wind will become scoured. Cornices will also develop above North to East aspects. The avalanche hazard will be Moderate.

Forecast Weather Influences: Winds will be mostly storm force South-Westerlies veering West-South-Westerly during the day. Overnight the freezing level will be around 900 metres, then rising above the summits, falling again by dawn to become 700 metres later. Precipitation overnight will become rain at all levels, while later in the period snow is anticipated above 600 metres. Observed Weather Influences: Light snow gradually turned to rain at all levels. The wind was gale force and mainly from the South-West during the day, veering Westerly later. The freezing level was at 1200 metres at midday, falling to 900 metres by the end of the period. ObservedSnowStability: Localised accumulations of moist windslab are present on North-East to South-East aspects above 1000 metres. At all elevations there has been significant snow loss due to the fluctuating temperatures. The old snow is mostly confined to coire back walls where it is firm, well bonded and stable. The avalanche hazard is Low.