Waadtländer Voralpen

Snowpack

The surface of the snowpack has become faceted this week, especially on shady slopes. On Friday, southerly winds created small localised snowdrift accumulations. With little fresh snow in the south and strong southerly winds in the north, these are still continuing to grow a little.

The old snowpack varies from region to region:

• in those regions south of a line Rhone to Rhine, there are weak layers in the lower part of the snowpack. These are particularly pronounced in Ticino, central Grisons, Engadine and the southern valleys of Grisons on wind-protected shady slopes and it is in particular here that avalanches may sweep away the entire snowpack. In the last few days, only a few avalanches have been triggered in the old snowpack, but some of these were dangerously large.
• in those regions north of a line Rhone to Rhine, avalanches are possible, especially in the upper part of the snowpack. Fractures in deeper layers of the old snowpack are unlikely here.

Gliding avalanches are still possible, and can be large in isolated cases.

Weather forecast to Saturday

In the north, there will be sunny spells with longer periods of sunshine in regions exposed to the foehn wind. In the south, it will be very cloudy with light precipitation. The snowfall level will increase from 500 m to 1000 m.

Fresh snow

Until Saturday afternoon, above approximately 1200 m:

• central part of the southern flank of the Alps 5 to 10 cm
• a few centimetres along the Main Alpine Ridge

Temperature

At midday at 2000 m, between 0 °C in the north and -5 °C in the south

Wind

• Strong from the south to southwest at high altitudes, strong foehn wind in the valleys of the north
• In the south light to moderate southerly

Weather review for Friday

In the north and east, conditions were mostly sunny in the mountains with sunny spells in Valais. It was cloudy in the south, but still largely dry.

Fresh snow

-

Temperature

At midday at 2000 m around +1 °C in the north and -7 °C in the south.

Wind

From the south:

• moderate and locally strong in the north at high altitudes with a rising foehn wind in the upper valleys
• elsewhere light to moderate.

Outlook

On Sunday, the foehn wind will make conditions brighter in the north and east, with sunny spells in the west. There will be heavy cloud cover on the southern flank of the Alps and 10 to 20 cm of snow will fall above approximately 1200 m but amounts are still uncertain. The wind will subside somewhat but remain moderate at higher altitudes. On Monday, cloud cover will be broken to heavy. Above approximately 1000 m, a further 5 to 10 cm of snow will fall in the south while a few centimetres will fall locally over the course of the day in the north. The southwesterly wind will freshen as the day progresses.

Avalanche danger will increase slightly on Sunday in the south with fresh snow but will not change significantly elsewhere. Persistent weak layers will remain in Valais, Ticino and Grisons.