At elevated altitudes a considerable avalanche danger will be encountered in some regions
Edition: 3.5.2021, 17:00 / Next update: 4.5.2021, 18:00
Snowpack
After a cool but sunny day on Monday, a crust has formed on the surface of sunny slopes up to high altitudes. Loose snow capable of being transported by the wind is still to be found in particular on steep shady slopes at high altitudes and generally in the high Alpine regions.
Underneath the fresh snow and snow drift accumulations of recent days, the old snow is thoroughly moist on east, south and west facing slopes below approximately 3000 m. On north facing slopes between 2200 and 2500 m, in recent days it has become moist all the way through for the first time, and thus weakened.
Observed weather on Monday, 03.05.2021
In the first half of the night the precipitation ceased in the east as well, and the skies cleared from the west. It was sunny during the day, but for some cumulus humilis cloud.
Fresh snow
With the snowfall level reaching down to approximately 1100 m, in the period from Sunday afternoon until the precipitation ceased during Sunday night, the following amounts of snow fell:
  • Extreme west of Lower Valais, central and eastern parts of the northern flank of the Alps: 5 to 10 cm
  • Elsewhere: smaller amounts, none in the south
Temperature
At midday at 2000 m: between -2 °C in the north and +2 °C in the south
Wind
  • During the night, frequently moderate from the north
  • During the day, mostly light from the west
Weather forecast through Tuesday, 04.05.2021
The night will be overcast in the south, but otherwise clear. On Tuesday in the north, it will be partly sunny despite high-altitude cloud. In the afternoon, the cloud will become denser from the west. The south will be cloudy all day.
Fresh snow
In the south, a few snowflakes will fall above approximately 1800 m.
Temperature
At midday at 2000 m: about +3 °C in the north and +1 °C in the south
Wind
  • The wind will strengthen to become strong to storm force during the day on the northern flank of the Alps, otherwise it will be moderate to strong.
  • In the northern valleys, a developing foehn situation.
Outlook through Thursday, 06.05.2021
Wednesday
It will be very cloudy with precipitation. 10 to 20 cm of snow will fall on the northern flank of the Alps, and up to 40 cm will fall in the extreme west of Lower Valais. In the rest of southern Valais and in Ticino and Grisons, only a little snow will fall. The snowfall level will drop from 1800 to 1300 m. The wind will be strong, sometimes storm force at elevated altitudes, from the west. In the south and in Valais as well in some cases, there will be bright spells as the day progresses.
As a consequence of fresh snow and snow drift accumulations, the danger of dry avalanches will increase in the north, even significantly in the extreme west of Lower Valais. In the afternoon in the west, moist snow slides originating in the fresh snow are to be expected.
Thursday
After bright spells in the morning, it will become very cloudy as the day progresses. In the west and north, snow will fall above approximately 2000 m, but the quantities are likely to be small. A strong westerly wind will persist.
The avalanche danger will not change significantly.