Vallée de Joux

New snow and drifted snow from the past week is lying on pronounced weak layers, especially on wind-protected shady slopes. South of a line from the Rhône to the Rhine, the entire snowpack is often faceted and loose. In addition, with the strong southerly winds at times, some highly visible, prone-to-triggering wind slabs have formed over the past three days. On the southern flank of the Alps, the fresh snow from Friday and Saturday was deposited on top of an equally weak snowpack. 

It is possible for medium and large-sized avalanches to be triggered in the old snowpack over a wide area. The snowpack on northern and eastern slopes in Valais and northern Grisons is particularly prone to triggering. Avalanches may also be triggered in the old snowpack on the northern flank of the Alps. Remote triggering, sometimes over long distances, is still possible.

It was mostly cloudy in the west and south. On the southern flank of the Alps, snow fell at times above approximately 1400 m. In the north and east, it was quite sunny with foehn winds.

Fresh snow

From Saturday afternoon to Sunday afternoon, the following amounts of snow fell above approximately 1500 m:

• Great St. Bernard, western Ticino, southern Simplon region: 5 to 10 cm
• Rest of the Main Alpine Ridge and south of this: a few centimetres;

Temperature

At midday at 2000 m, between +3 °C in the north and -2 °C in the south

Wind

From south-east to south

• Moderate to strong in the north, strong foehn wind at times in the regions exposed to the foehn wind in the north
• Mostly light south of the Main Alpine Ridge

In Ticino and southern Grisons, it will be mostly overcast with some snow at times. Elsewhere it will be mostly sunny.

Fresh snow

Southern Simplon region, Ticino and southern Grisons: up to 5 cm

Temperature

At midday at 2000 m, around 0 °C in the north and -4 °C in the south

Wind

Moderate to strong southerly foehn wind in the north, elsewhere light to moderate

On Tuesday it will still be partly cloudy but dry in the south, and mainly sunny elsewhere. It will be sunny everywhere in the mountains on Wednesday. The southerly wind will slowly subside.

The avalanche danger will continue to decrease but only slowly. Weak layers in the old snowpack will remain prone to triggering, especially in the inneralpine regions.