Increase in avalanche danger in the west and in the north
Edition: 26.11.2021, 17:00 / Next update: 27.11.2021, 18:00
Snowpack
In western and northern regions there is still little snow on the ground. In the Jura and Prealps, fresh snow is falling mostly on bare ground. Most of the snow on the ground (30 to 50 cm) lies in the Upper Valais sector of the Main Alpine Ridge, in northern Ticino and in the central and southern parts of Grisons.
On shady slopes the snowpack is expansively metamorphosed (faceted) for the most part, thus, it is generating an unfavourable snow base. On sunny slopes there are are variety of crusts inside the snowpack. The surface is hardened in some places. Steep south-facing slopes up to approximately 2200 m, in the northern and western regions up to 2600 m in some places, have been free of snow to a great extent.
Observed weather
On Tuesday and on Wednesday it was frequently sunny and dry. On Thursday afternoon in the southern regions, light snowfall set in. On Friday in the northern regions there was intermittent light snowfall. In the southern regions it was partly sunny on Friday. The snowfall level in the southern regions lay at 1000 to 1500 m, in the northern regions below 1000 m.
Fresh snow
In the western and southern regions, approximately 5 to 10 cm was registered, in the eastern regions only a few centimetres
Temperature
Tuesday and Wednesday at between 0 and +4 °C, subsequently descending to -5 °C in the northern regions and to -1 °C in the southern regions on Friday
Wind
Winds were blowing generally from southerly directions, on Wednesday night at moderate to strong velocity, otherwise predominantly at light to moderate strength.
Weather forecast through Saturday, 27.11.2021
Skies are expected to be heavily overcast for the most part. During the afternoon in the western regions there will be isolated bright intervals. Snowfall is anticipated during the night down to low lying areas, most of all in the Engadine and in the southern valleys of Grisons; during the daytime over widespread areas in the western and the northern regions.
Fresh snow
Between Friday afternoon and Saturday afternoon above approximately 1500 m:
  • furthermost western part of Lower Valais, Jura: 15 to 30 cm;
  • remaining parts of Valais, northern flank of the Alps as well as the region from Avers over the Upper Engadine into Val Poschiavo: 5 to 15 cm;
  • in the other regions of Switzerland, only a few centimetres; in the furthermost south it is expected to remain dry.
Temperature
Midday temperatures at 2000 m: -8 °C in the western and northern regions; -5 °C in the southern and eastern regions.
Wind
  • In the western and northern regions, as well as at high altitudes in the eastern regions, strong-velocity winds from southwesterly directions;
  • in the southern regions, moderate-strength winds from westerly directions, shifting to northwesterly.
Outlook through Monday, 29.11.2021
In the northern regions an additional amount of snowfall down to low lying areas is anticipated. Between Saturday evening and Monday evening in the Valais, on the northern flank of the Alps, in northern Grisons and in the Jura, 20 to 40 cm of fresh snow is expected. In the southern regions it will be partly sunny, accompanied by strong-velocity northerly winds. It will be very cold. The avalanche danger levels are expected to increase further in the areas of precipitation more than anywhere else.