In the north a high avalanche danger will be encountered in some regions
Edition: 29.11.2021, 17:00 / Next update: 30.11.2021, 18:00
Snowpack
The fresh fallen snow of recent days is being transported by strong to storm-strength westerly to northwesterly winds, and snowdrift accumulations which are prone to triggering are thereby being generated.
Prior to the snowfall of the last few days there was only a small amount of snow on the ground in the western and northern regions. In the Jura region and the Prealps the snowfall fell on bare ground for the most part. On shady slopes the thin old snowpack has been expansively metamorphosed by and large, thereby generating an unfavourable snow base. On sunny slopes there is a variety of crusts embedded inside the snow cover and the surface is hardened in some places. Steep south-facing slopes were free of snow up to approximately 2200 m by and large, in the western and southern regions up to 2600 m in some places.
Observed weather on Monday, 29.11.2021
In the northern regions skies were heavily overcast and snowfall was registered down to the low lying areas, snowfall was persistent and heavy on the northern flank of the Alps. In the inneralpine regions skies were partly bright, south of the Main Alpine Ridge it was partly sunny as a result of the northerly winds.
Fresh snow
Between Sunday afternoon and Monday afternoon, 20 to 40 cm of fresh snow was registered on the northern flank of the Alps, as much as 60 cm of fresh snow from place to place in the barrier-cloud regions of the eastern sector of the Bernese Alps as far as the Glarus Alps; in the other regions of Switzerland there was less.
Since the launch of this period of precipitation on Thursday night, the following amounts of fresh snow have been registered:
  • Northern flank of the Alps from the eastern sector of the Bernese Alps as far as the Glarus Alps: 50 to 80 cm;
  • remaining sectors of the northern flank of the Alps, northern Valais, Grisons north of the Anterior Rhine, central sector of the southern flank of the Alps, Main Alpine Ridge from San Bernardino Pass as far as Ofen Pass and southwards therefrom: 30 to 50 cm;
  • in the other regions of Switzerland, 15 to 30 cm.
Temperature
At midday at 2000 m, between -10 °C in the northern regions and -7 °C in the southern regions.
Wind
Winds will be blowing from northerly directions: mostly at moderate strength during the nighttime hours, during the daytime at light to moderate strength, though at strong velocity in some places of the Jura region, in high alpine regions and in the south.
Weather forecast through Tuesday, 30.11.2021
During the nocturnal hours the snowfall will come to an end in the northern regions. During the daytime in the north, skies will be heavily overcast for the most part and during the afternoon, snowfall will set in again. The snowfall level is expected to ascend during the course of the day to approximately 1000 m. On the southern flank of the Alps it will be predominantly sunny as a result of slackening northerly winds.
Fresh snow
Between Monday afternoon and Tuesday afternoon, the following amounts of fresh snow are anticipated above approximately 1200 m:
  • Northern flank of the Alps from the eastern sector of the Bernese Alps into the Alpstein region, northern Grisons: 10 to 20 cm;
  • in the other regions of Switzerland, only a few centimetres; in the southern regions it is expected to remain dry.
Temperature
Temperatures will rise, at midday at 2000 m to -6 °C.
Wind
Winds will be blowing at moderate to strong velocity, intermittently at strong to storm-strength on the Alpine Ridges; subsequently winds will shift from northerly to northwesterly, and to westerly on the northern flank of the Alps.
Outlook through Thursday, 02.12.2021
On Tuesday night in the northern and the eastern regions an additional amount of snowfall is anticipated. On Wednesday morning in the northern regions it will be partly sunny, in the inneralpine and southern regions quite sunny. During the course of the day, cloud cover is expected to move in from the northwest. Precipitation will set in over widespread areas, which will subsequently persist on Thursday. The snowfall level in the northern regions will initially lie at 1200 m. The snowfall level will subsequently descend to approximately 700 m on Thursday. In the furthermost western and northern regions, it is expected that 20 to 40 cm of fresh snowfall will be registered. South of the Main Alpine Ridge it will be partly sunny on Thursday.
The danger of dry-snow avalanches will decrease in the northern regions on Wednesday, however danger levels will again increase from region to region on Thursday as new snowfall sets in. As a result of the rainfall at lower altitudes, moist-snow slides can be expected. In the southern regions the avalanche danger levels will decrease a little.