At elevated altitudes a moderate avalanche danger will be encountered in some regions
Edition: 27.11.2021, 17:00 / Next update: 28.11.2021, 18:00
Snowpack
There is only a small amount of snow on the ground in the western and northern regions from the rounds of snowfall this weekend. In the Jura and the Prealps the snowfall fell for the most part on bare ground. Most of the snow fell in the Upper Valais sector of the Main Alpine Ridge, in northern Ticino and in the central and southern parts of Grisons, with 30 to 50 cm of fresh snow at 2000 m altitude.
On shady slopes the thin old snowpack has expansively metamorphosed (faceted) to a great extent, thus forming an unfavourable snow base. On sunny slopes various crusts are embedded inside the old snowpack, and the snowpack surface is frequently hardened in some places. Steep south-facing slopes were free of snow up to about 2200 m over widespread areas, in western and northern regions up to 2600 m.
Observed weather on Saturday, 27.11.2021
In the western and the northern regions, skies were variably cloudy to heavily overcast, accompanied by shower-like snowfall and some sunny intervals. In the southern regions skies were predominantly overcast; in the inneralpine regions of the Valais and Grisons it was quite sunny. The snowfall level in northern regions descended to approximately 500 m, in the southern regions to approximately 800 m.
Fresh snow
Between Friday afternoon and Saturday afternoon in the Jura region, in the western sector of the northern flank of the Alps as well as in the southern Engadine and the southern valleys of Grisons, 5 to 15 cm of fresh snow was registered; from place to place as much as 20 cm of fresh snow. Since the launch of this period of precipitation on Thursday night, the following amounts of fresh snow have been registered above approximately 1200 m:
  • furthermost western part of Lower Valais, southern Engadine and southern valleys of Grisons: 10 to 25 cm;
  • Jura region, northern flank of the Alps, remaining regions of the Valais, Ticino: 5 to 15 cm;
  • remaining regions of Grisons: only a few centimetres.
Temperature
At midday at 2000 m, between -7 °C in the northern regions and -4 °C in the southern regions.
Wind
In the northern regions, winds were blowing intermittently at moderate to strong velocity, elsewhere predominantly at moderate strength at high altitudes, from southwesterly to westerly directions.
Weather forecast through Sunday, 28.11.2021
It is expected to be very cold, and snowfall will extend down to low lying areas. On Saturday night in the southern regions and the eastern regions, snowfall is anticipated. During the daytime on Sunday in the northern regions, skies will be heavily overcast for the most part, and intermittent snowfall is anticipated. In the southern regions the snowfall will come to an end on Sunday morning and southwards of the Main Alpine Ridge it will become partly sunny during the course of the day, accompanied by northerly winds.
Fresh snow
Between Saturday afternoon and Sunday afternoon:
  • central and eastern sectors of the northern flank of the Alps, Grisons: 10 to 20 cm;
  • Jura region, western sector of the northern flank of the Alps, Valais, Ticino: 5 to 10 cm;
Temperature
At midday at 2000 m, between -10 °C in the northern regions and -7 °C in the southern regions.
Wind
To start with, moderate-velocity winds from southwesterly to westerly directions, subsequently during the daytime blowing at moderate to strong velocity from the northwest at high altitudes.
Outlook through Tuesday, 30.11.2021
In the northern regions the snowfall will persist on Monday, then slacken off somewhat during the daytime on Tuesday. It will remain cold. Between Sunday afternoon and Tuesday afternoon on the northern flank of the Alps and in northern Grisons, 30 to 50 cm of fresh snowfall is anticipated. At high altitudes and in the southern regions, a strong-velocity northerly wind will be blowing. In the southern regions it will be partly sunny, the northerly winds will slacken off on Tuesday.
Avalanche danger levels are expected to increase over wide-ranging areas, significantly so in the major areas of precipitation of the north.