At high altitude a considerable avalanche danger will be encountered in some regions
Edition: 7.4.2021, 17:00 / Next update: 8.4.2021, 18:00
Snowpack
As a result of fresh fallen snow and moderate-strength, in some regions strong-velocity winds, fresh snowdrift accumulations were generated primarily in high altitude areas of the regions where snowfall has been heaviest on the northern flank of the Alps. Both fresh snow and freshly generated snowdrifts were deposited atop a hard, frozen, in high-alpine regions heavily wind-impacted snowpack surface. Fresh snow and snowdrifts can be easily triggered particularly in very steep terrain. Fractures deeper down in the snowpack are no longer to be expected. Due to the low temperatures of recent days, the old snowpack is frozen and stable.
As a result of sunshine and daytime warming, numerous loose-snow slides can be expected to unleash from the fresh fallen snow on Thursday.
Observed weather on Wednesday, 07.04.2021
On Tuesday night, skies were heavily overcast for the most part, on the southern flank of the Alps skies were partly clear. Particularly north of an imaginary Rhine-Rhone line there was snowfall, south of that line it remained by and large dry. During the daytime on Wednesday there was additional snowfall particularly in eastern regions in the form of showers, in the southern and western regions there was some sunshine.
Fresh snow
Between Tuesday and Wednesday afternoon:
  • on the northern flank of the Alps, 15 to 30 cm over widespread areas, up to 40 cm particularly further to the east;
  • from the Lower Valais and northern Grisons as far as northern Grisons: 5 to 15 cm;
  • further to the south, less, or else it remained dry.

Since Monday night and until Wednesday afternoon:
  • central and eastern sectors of the northern flank of the Alps: 30 to 50 cm; along the Prealps from Vierwaldstättersee into Alpstein, as much as 70 cm;
  • western sector of the northern flank of the Alps, northern and central parts of Lower Valais, Prättigau: 15 to 30 cm;
  • further to the south, less, or else it remained dry.
Temperature
at midday at 2000 m, -12 °C.
Wind
Winds were northwesterly
  • in the western regions, winds were blowing at moderate strength particularly at heightened altitudes, in some places at strong velocity, elsewhere at light strength;
  • in the eastern and the southern regions, generally blowing at moderate strength, at heightened altitudes at strong velocity in some places.
Weather forecast through Thursday, 08.04.2021
On Wednesday night the precipitation will come to an end in the northeastern regions. Skies are expected to clear from the west and the south. In the early morning hours there will be some residual cloud only in the eastern regions, in the other regions of Switzerland it will be predominantly sunny during the daytime.
Fresh snow
By Thursday morning:
  • in the eastern sector of the northern flank of the Alps and in the northern and eastern regions of Grisons: only a few centimetres;
  • in the other regions of Switzerland, it will remain dry.
Temperature
Temperatures are expected to rise, at midday at 2000 m to between -4 °C in the western regions and -7 °C in the eastern regions.
Wind
Winds at heightened altitudes will be blowing predominantly at moderate strength from westerly to northwesterly directions; during the course of the day winds are expected to slacken off.
Outlook through Saturday, 10.04.2021
Friday
To start with, it will be rather sunny, accompanied by some high-altitude clouds. During the course of the day the cloud cover is expected to increase from the south. Winds at heightened altitudes will be blowing at moderate to strong velocity from westerly to southwesterly directions. In the Alpine valleys of the north, moderate to strong-velocity foehn wind will arise. The zero-degree level will ascend in the northern regions to approximately 2200 m, in the southern regions to approximately 1600 m. The danger of dry-snow avalanches is not expected to change signficantly. During the course of the day, moist-snow slides will be possible on steep south-facing slopes below approximately 2800 m.
Saturday
In the eastern regions it will be intermittently sunny as a result of foehn influence, in the western regions conditions will be variable, in the southern regions skies will be heavily overcast. The southwesterly winds and foehn wind in the Alpine valleys of the north will be blowing at moderate to strong velocity. On the southern flank of the Alps a small amount of snowfall is anticipated above approximately 1600 m. The avalanche danger levels are expected to gradually decrease.