Waadtländer Voralpen

Snowpack

There was heavy snowfall in some regions in the south this weekend. In the north, strong to storm-force southerly winds caused the old snow that was still loose and close to the surface to drift. There was the potential for avalanches to be triggered, especially in the various layers of new and drift snow. With Monday's incoming radiation and warmer temperatures, the near-surface layers have mostly settled well. Loose snow still lies on very steep north-facing slopes in the high Alpine regions.

Before last week's cold snap, the old snowpack on east-, south- and west-facing slopes was already soaked up to approximately 3000 m and on north-facing slopes up to approximately 2500 m. As temperatures rise, the moistening process will slowly progress again. Particularly in the inneralpine regions, wet slab avalanches are possible on north-facing slopes as the moistening progresses, some of which may be large.

Gliding avalanches are still possible, increasingly so once again at high altitudes.

Weather forecast until Tuesday, 30.04.2024

Monday night into Tuesday will be partly clear in the north and east. It will be overcast on the western part of the Main Alpine Ridge and in northern Ticino, with some precipitation falling by the early morning. The snowfall level will be around 2400 m. During the day, it will be quite sunny in the west and east. Saharan dust will obscure visibility.

New snow

From Monday afternoon to Tuesday morning, the following amounts of fresh snow are expected above approximately 2800 m:

• Main Alpine Ridge west of the Nufenen Pass: 5 to 10 cm;
• dry elsewhere.

Temperature

At midday at 2000 m, +9 °C in the west, +11 °C in the east and +5 °C in the south.

Wind

There will be a moderate to strong southerly wind, and a sometimes strong foehn wind from the south in the regions of the north exposed to the foehn wind.

Weather review for Monday, 29.04.2024

It was quite sunny. On the central part of the Main Alpine Ridge, it was partly cloudy, with light snowfall during the night.

New snow

From Sunday afternoon to Monday morning, the following amounts of fresh snow were recorded above approximately 2200 m:

• Lower Valais Main Alpine Ridge and Simplon region: locally up to 20 cm;
• rest of the Main Alpine Ridge: a few centimetres.

Temperature

At midday at 2000 m, +8 °C in the west, +7 °C in the east and +4 °C in the south.

Wind

There was a southerly wind:

• moderate to strong in the north at high altitudes;
• in the regions of the north exposed to the foehn wind, a strong foehn wind from the south during the night, easing in the course of the day.

Trend until Thursday 02.05.2024Wednesday, 01.05.2024

On Wednesday it will still be partly sunny in the east, while in the south and west it will be mostly cloudy with precipitation. The precipitation will centre on the Main Alpine Ridge in Upper Valais. There, 40 to 70 cm of new snow is possible at high altitudes by the evening. Below 2500 m, the precipitation will fall as rain. There will be a moderate to strong southeasterly wind.

The danger of dry and wet avalanches will increase, especially in Valais and northwestern Ticino, and will be significant on the Main Alpine Ridge in Upper Valais. In the other regions, the avalanche danger will not change significantly.

Thursday, 02.05.2024

It will be mostly very cloudy with occasional precipitation. The snowfall level will drop to around 2000 m. On and to the south of the Main Alpine Ridge, 20 to 30 cm of new snow will fall at high altitudes, and up to 50 cm from the Saas Valley to the Simplon region. The southerly wind will be moderate, strong at times at high altitudes.

The danger of dry avalanches will continue to increase in the regions exposed to heavier precipitation. Level 4 may be reached on the Main Alpine Ridge in Upper Valais.