Waadtländer Voralpen

As the day progresses a moderate danger of wet avalanches will be encountered over a wide area

As the day progresses a moderate danger of wet avalanches will be encountered over a wide area

Individual avalanche prone locations for dry avalanches are to be found in particular on extremely steep slopes at high altitude. As a consequence of a strong southerly wind, small wind slabs formed in the last two days. They are to be evaluated with care and prudence in particular in extreme terrain. Apart from the danger of being buried, restraint should be exercised as well in view of the danger of avalanches sweeping people along and giving rise to falls. Only a little snow is lying. The snowpack will be wet all the way through. On very steep slopes individual gliding avalanches and wet snow slides are possible. Caution is to be exercised in areas with glide cracks.

As a consequence of predominantly clear and cold nights, the snowpack surface freezes over widespread areas and forms a crust which is capable of bearing loads. During the daytime hours this crust softens and slushes up. Loosely packed snow is deposited generally only in very few spots on steep north-facing slopes and in the high alpine regions. The snowpack on south-facing slopes below 2500 to 2800 m, on east-facing and west-facing slopes below 2000 to 2300 m, is thoroughly wet. On north-facing slopes the process of becoming thoroughly wet has begun below 1700 to 2000 m. Gliding avalanches have been observed in the northern regions of Switzerland where snowfall has been heaviest more than anywhere else, and were seen to grow to large size in some places. In more deeply embedded layers inside the snowpack, particularly in the southern Valais as well as in the inneralpine and the southern regions of Grisons, there are pronounced weak layers evident. Nevertheless, from the end of February until the middle of March there have been no further fractures of dry-snow avalanches triggering in these layers which have been recorded. Currently, as the snowpack begins to moisten to a further extent, fractures inside these weak layers are once again becoming possible, as avalanche triggerings by persons have recently demonstrated.

The skies on Saturday night on the southern flank of the Alps were overcast in some places, in the other regions of Switzerland predominantly clear. During the daytime on Sunday it was predominantly sunny in all regions of Switzerland. Fresh snow: - Temperature: At midday at 2000 m, between +3 °C in the western sector of the northern flank of the Alps and -3 °C from the Valais over the Ticino as far as Grisons. Wind: Winds were blowing from southerly directions, - during the nocturnal hours at strong velocity, from region to region at storm strength; plus moderate-to-strong velocity foehn wind in the Alpine valleys of the north; - during the daytime hours, slackening off. Nocturnal skies on Sunday night in the northern regions will be predominantly clear, on the Main Alpine Ridge and southwards therefrom overcast in some places. During the daytime hours it will be predominantly sunny in all regions. Fresh snow: - Temperature: At midday at 2000 m, between 0 °C in the northern regions and -3 °C on the southern flank of the Alps. Wind: Winds will be blowing at predominantly light strength from easterly directions.

The nighttime skies are expected to be clear and cold, the daytimes sunny and, incrementally, becoming somewhat warmer. The avalanche danger levels will continue to be subject to a daytime danger cycle, i.e. a favourable avalanche danger situation in the early morning, subsequently increasing danger of wet-snow avalanches during the course of the day.