In the south a high avalanche danger will be encountered in some regions
Edition: 23.4.2022, 17:00 / Next update: 24.4.2022, 18:00
Snowpack
As a result of fresh fallen snow and winds, wide-ranging snowdrift accumulations are being generated at high altitudes in southern regions. These accumulations are prone to triggering in some places. The fresh snow is being deposited atop bare ground at high altitudes on south-facing slopes. On north-facing slopes the snow level prior to the snowfall lay at 2000 m. Previous to the current round of snowfall the snowpack evidenced pronounced effects of sunshine over widespread areas. Thus, the bonding to the layers of fresh fallen snow and freshly generated snowdrifts was relatively favourable. Only on north-facing slopes in the high alpine regions was the snowpack surface still loosely-packed in some places. There, the bonding of fresh snow to the old snowpack can be inadequate in some places.
South-facing slopes are thoroughly wet far up into high alpine regions; west-facing and east-facing slopes are wet below approximately 3000 m; north-facing slopes below approximately 2400 m. In the major areas of precipitation it is possible that avalanches can fracture down into the entire thoroughly wet snowpack and sweep it along.
Observed weather on Saturday, 23.04.2022
Nighttime skies on Friday were still somewhat clear to start with, subsequently they became heavily overcast. In the southern regions, precipitation set in. During the daytime on Saturday in the northeastern regions there were bright intervals, in the other regions of Switzerland skies remained predominantly overcast and in the southern regions there was further precipiation registered. The snowfall level lay at 2000 m
Fresh snow
Between Friday evening and Saturday afternoon the following amounts of fresh snow were registered above approximately 2200 m:
  • Simplon region, southern Goms, Bedretto and upper valleys of Maggia: 15 to 25 cm;
  • remaining parts of the Main Alpine Ridge from the Great St. Bernard into Val Bregaglia, as well as the central sector of the southern flank of the Alps: 5 to 15 cm;
  • in the remaining regions of Switzerland, only a few centimetres; or else it remained dry.
Temperature
At midday at 2000 m, +5 °C in the northern regions and 0° C in the southern regions.
Wind
  • Winds were southerly, during the nighttime hours blowing at light to moderate strength, during the daytime hours at strong velocity at high altitudes;
  • in the Alpine valleys of the north, southerly foehn wind arose.
Weather forecast through Sunday, 24.04.2022
Skies are expected to be heavily overcast and intermittent precipitation is anticipated, intensive on the Main Alpine Ridge and in the southern regions. During the daytime hours in inneralpine regions, bright intervals are possible. The snowfall level will descend to approxiamtely 1500 m on Saturday night, then on Sunday afternoon ascend again slightly.
Fresh snow
Between Saturday afternoon and Sunday afternoon, the following amounts of fresh snow are anticipated above 1800 m:
  • Monte Rosa, Mattmark, southern Simplon region, southern Goms, central sector of the southern flank of the Alps, Val Bregaglia, Bernina region, Val Poschiavo: 40 to 60 cm;
  • Trient region, remaining parts of the Main Alpine Ridge as well as the eastern part of the Bernese Oberland: 20 to 40 cm;
  • remaining parts of the Valais, northern Lower Engadine: 10 to 20 cm; in the remaining regions of Switzerland, only a few centimetres.
Temperature
At midday at 2000 m in the inneralpine parts of Grisons, +2 °C, in the other regions of Switzerland -1° over widespread areas.
Wind
  • Winds during the nocturnal hours on Saturday night will be southerly, blowing at storm strength, in the Alpine valleys of the north foehn wind blowing at strong velocity;
  • slackening off during the daytime hours on Sunday and shifting to westerly.
Outlook through Tuesday, 26.04.2022
Monday
In the western and the northern regions, snowfall is expected above approximately 1600 m. In the Lower Valais and on the northern flank of the Alps, approximately 15 to 30 cm of fresh snow is expected. In the southern regions the precipitation will slacken off and it will become partly sunny. The danger of dry-snow avalanches is expected to increase in the northern regions. In the southern regions the danger of dry-snow avalanches will decrease, there are nearly no further naturally triggered avalanches to be expected. As a consequence of solar radiation in the southern regions, however, moist-snow slides can be expected to release from the fresh fallen snow.
Tuesday
In the western regions it will be rather sunny, in the southern regions partly sunny. In the northeastern regions skies will still be overcast, however only a small amount of snowfall is anticipated. At high altitudes more than anywhere else, strong-velocity westerly winds can generate fresh snowdrift accumulations. In the major areas of precipitation in the south, the danger of dry-snow avalanches is expected to diminish. As a consequence of solar radiation and daytime warming, wet-snow avalanches releasing from the fresh snow can be expected in the Valais and on the southern flank of the Alps more than anywhere else.