Ybrig

Snowpack

The large amount of new snow in the west and south this week is increasingly settling and consolidating. Near-surface layers are still prone to triggering in some places. In addition, increasing southerly winds on Sunday will produce snowdrift accumulations that can easily be triggered by people. In the inneralpine regions of Grisons in particular, where there has been only little fresh snow, weak layers in the old snowpack are still sometimes prone to triggering.

The old snowpack is water-saturated on southern slopes in the high alpine regions and on eastern and western slopes up to around 2800 m. On northern slopes, most of the old snowpack is water-saturated up to around 2400 m. At intermediate altitudes, the fresh snow fell widely on snowless ground. As a consequence of warming and solar radiation, wet and gliding avalanches are to be expected, in the fresh snow areas also at medium altitudes. These can become large in the main precipitation areas.

Weather forecast to Saturday

It will be overcast in the south and a few centimetres of snow will fall above approximately 2000 m. In the north, it will be quite sunny and milder again after a mostly clear night.

Fresh snow

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Temperature

• Rising in the north, reaching +7 °C at midday at 2000 m, with the zero-degree level rising to around 3000 m
• +2 °C in the south

Wind

• Light to moderate during the night, with moderate to strong winds from southwest to south at high altitudes during the day
• Increasingly strong southerly foehn wind in the foehn valleys of the north

Weather review for Friday

There was continued little but widespread precipitation during the night into Friday. The snowfall level was at 1200 to 1400 m in the north and Valais, and 1800 to 2000 m in the south and the Engadine.

During the day, it was mostly sunny in the west and south at high altitudes. In the east, it was initially cloudy but sunny at times during the course of the day.

Fresh snow

During the night to Friday, 5 to 10 cm of snow fell over a wide area, with up to 20 cm in southern Valais.

From Tuesday until Thursday night to Friday, the following amounts fell above approximately 2000 m in the west and above approximately 2600 m in the south:

• Upper Valais and the neighbouring Bernese Oberland to the north: 150 to 180 cm, and up to over 200 cm from the Saas valley via the Simplon region to Binntal
• Western Lower Valais, rest of the western part of the northern flank of the Alps, western Gotthard region, Val Bedretto, Valle Maggia: 70 to 150 cm
• Further east: mostly less than 30 cm, largely dry in the northeast

Temperature

At midday at 2000 m, between 0 °C in the north and Valais and +3 °C in the south

Wind

Light to moderate from westerly directions

Outlook

On Sunday, it will be partly sunny in the north and very cloudy with precipitation in the south. The snowfall level will be around 1900 m. On the western part of the Main Alpine Ridge in Valais and in western Ticino, 20 to 40 cm of snow is expected to fall at high altitudes. There will be moderate to strong southerly wind. The avalanche danger will increase slightly in the south with fresh snow and also in the north due to fresh snowdrifts. The risk of wet and gliding avalanches will be subject to daytime changes, especially in the north. On the Main Alpine Ridge in Valais, more wet snow slides and avalanches are to be expected due to the rain at intermediate altitudes.

On Monday, it will be mostly sunny in the west and sunny at times in the east. In the south, a little snow will continue to fall above approximately 2000 m. The wind will ease and be light to moderate, blowing from the south. The risk of dry avalanches will decrease. Wet and gliding avalanches are still to be expected, especially in the north and in Valais.