Saint-Cergue

Snowpack

The old snow surface from last week, angular in structure and partly covered with surface hoar, has in recent days become a weak near-surface layer prone to triggering in many places as a result of the wind and some new snow. In the west, this layer mostly no longer exists because the rain on Wednesday soaked it down to around 2200 m. Above this altitude and in the other regions, where there was little or no rain on Wednesday, the weak layer is still present and prone to triggering, especially on slopes that are largely sheltered from the wind. With the expected arrival of fresh snow, avalanches triggered or occurring naturally in this weak layer may be larger than before.

There are hardly any critical weak layers deeper in the snowpack.

As the snowfall level drops, wet avalanche activity will decrease.

Weather forecast for Thursday, 18.01.2024

It will be very cloudy with widespread precipitation, with the largest amounts falling in the west. The snowfall level will gradually drop from 2200 m on Wednesday evening to 1600 m on Thursday afternoon.

New snow

From Wednesday afternoon to Thursday afternoon, the following amounts of fresh snow are expected above approximately 2500 m:

• extreme west of Lower Valais along the border with France: 40 to 60 cm;
• rest of Lower Valais, northern Valais, western part of the northern flank of the Alps: 20 to 40 cm;
• southern Upper Valais, rest of the northern flank of the Alps, rest of the Main Alpine Ridge: 10 to 20 cm; less in the other regions.

Temperature

At midday at 2000 m, around 0 °C.

Wind

There will be a westerly to southwesterly wind, strong to storm strength in the north and generally at high altitudes.

Weather review for Wednesday, 17.01.2024

It was mostly cloudy with clear spells due to the foehn wind. Precipitation fell in the west and north. The snowfall level rose rapidly towards 2200 m in the early morning.

New snow

From Tuesday evening to Wednesday afternoon, the following amounts of fresh snow were recorded above approximately 2500 m:

• Vaud Alps, extreme west of Lower Valais, northern Valais: 15 to 30 cm;
• rest of Valais, rest of the northern flank of the Alps, Bedretto: 5 to 15 cm; elsewhere: less or it remained dry.

Temperature

At midday at 2000 m, between +3 °C in the west and north and -4 °C in the south.

Wind

There was a southwesterly wind:

• strong, sometimes storm force, in the west and on the Main Alpine Ridge;
• otherwise moderate to strong.

Trend until Saturday, 20.01.2024

The precipitation will end during Thursday night into Friday. A further 5 to 10 cm of snow will fall widely, with up to 20 cm on the northern flank of the Alps. During the day, it will be mostly sunny in the west and south and increasingly sunny elsewhere. On Saturday, it will be sunny in all regions. In the north, there will be mostly weak to moderate northeasterly winds, with a strong northerly foehn wind blowing for a time in the south on Friday. It will be very cold on both days.

The avalanche danger will decrease.