High avalanche danger will be encountered in some regions
Edition: 2.2.2022, 17:00 / Next update: 3.2.2022, 18:00
Snowpack
The very deep layers of fresh fallen snow and freshly generated snowdrifts which were unleashed in numerous places on Tuesday and on Wednesday lie deposited on west-facing, north-facing and east-facing slopes atop an unfavourable, expansively metamorphosed (faceted) weak layer.
More deeply embedded inside the snowpack in the Jura region, on the northern flank of the Alps and in the western part of the Lower Valais are deep rain crusts which formed in the final week of the old year and extend up to high altitudes in some places. These rain crusts stabilise the lower part of the snow cover below approximately 2700 m in these regions, so that avalanches can hardly ever fracture down to the more deeply embedded layers of the snowpack. From the southern Valais over the northern Ticino as far as Grisons, on the other hand, the entire snowpack is often expansively metamorphosed (faceted) and riddled with thin melt-freeze crusts. In these regions more than anywhere else, avalanches can sweep along the entire snowpack.
As a result of the measurably higher temperatures and the daytime increase in solar radiation, naturally triggered avalanches can be expected on sun-drenched slopes, in particular in the regions where snowfall has been heaviest. At intermediate altitudes on very steep grass-covered slopes, gliding avalanches can be expected.
Observed weather on Wednesday, 02.02.2022
In the northern regions, there was persistent snowfall registered. The snowfall level ascended on the northern flank of the Alps and in the Lower Valais to approximately 1400 m, in the Upper Valais and in Grisons the snowfall level lay at 1000 m. South of the Main Alpine Ridge it was dry as a result of the strong to storm-strength northerly winds and, in the Sotto Ceneri, quite sunny.
Fresh snow
Between Tuesday afternoon and Wednesday afternoon, the following amounts of fresh snow were registered above 1500 m:
  • central and eastern sectors of the northern flank of the Alps, northern and central Grisons, Engadine north of the Inn: 30 to 50 cm;
  • Bernese Oberland, northern Valais, southern Upper Valais, Engadine south of the Inn: 15 to 30 cm;
  • in the remaining regions of Switzerland, less; or else it remained dry.
Thus, overall since the beginning of this period of precipitation, the following amounts of fresh fallen snow have been registered:
  • central and eastern sectors of the northern flank of the Alps, northern Grisons: 60 to 90 cm, as much as 100 cm in the Glarus Alps;
  • Bernese Oberland, northern Valais, central Grisons, Engadine north of the Inn: 40 to 60 cm;
  • in the other regions of Switzerland, generally 15 to 30 cm;
  • in the furthermost southern regions it remained dry.
As a consequence of storm-strength winds, the snow depths which have been measured over small areas vary widely.
Temperature
At midday at 2000 m, -3 °C.
Wind
Winds were blowing at strong to storm velocity from northerly to northwesterly directions.
Weather forecast through Thursday, 03.02.2022
On Wednesday night in the northern and the eastern regions, the final burst of fresh snow is expected to fall. The snowfall level will lie at 1200 to 1400 m. During the daytime on Thursday in the northern regions, it will be partly sunny after the residual clouds have withdrawn, in the eastern regions it will be partly sunny. In the inneralpine regions and in the south it will be quite sunny.
Fresh snow
On Wednesday night above approximately 1500 m the following amounts of fresh snow are expected:
  • northern Alpine Ridge from the Aletsch region as far as the Säntis, northern Prättigau, Silvretta: 15 to 30 cm;
  • remaining parts of the northern flank of the Alps, central Grisons, Engadine: 5 to 15 cm;
  • in the remaining regions of Switzerland, less; on the southern flank of the Alps it is expected to remain predominantly dry.
Temperature
The zero-degree level is expected to ascend significantly, in the western regions at midday it will lie at 3000 m, in the eastern regions at approximately 2600 m.
Wind
  • Winds during the nocturnal hours and in general on the southern flank of the Alps will be blowing at strong velocity from northerly directions;
  • during the daytime, blowing at moderate strength from westerly directions.
Outlook through Saturday, 05.02.2022
On Friday on the northern flank of the Alps, it is expected to be still sunny to start with, subsequently cloud cover will move in from the northwest. In the inneralpine and southern regions it will be quite sunny. On Friday night, a small amount of snowfall is anticipated, falling down to low lying areas. Only on the southern flank of the Alps will it remain dry. On Saturday it will be quite sunny in the mountains.
Avalanche danger levels are expected to decrease. Gliding avalanches are possible particularly on very steep slopes in the central and eastern sectors of the northern flank of the Alps and in northern Grisons.