A generally favourable avalanche situation will prevail. Fresh wind slabs require caution
Edition: 11.3.2022, 17:00 / Next update: 12.3.2022, 18:00
Snowpack
As a result of strong-velocity southerly foehn wind in some places, snowdrift accumulations have been generated in the foehn-exposed regions more than anywhere else. These drifted masses lie deposited on top of expansively metamorphosed (faceted) old snow on north-facing slopes in particular and are prone to triggering.
More deeply embedded inside the snowpack in the southern Valais as well as in the inneralpine and southern regions of Grisons, weak layers are evident. Even though these weak layers are quite pronounced from place to place, since the end of February there have been no further avalanche releases registered as triggering from them. In the remaining regions of Switzerland, the snowpack structuring is more favourable.
During nocturnal hours when skies are frequently overcast, outgoing longwave radiation is reduced. Thereby, a melt-freeze crust forms on steep south-facing slopes which is hardly capable of bearing loads. As a consequence of solar radiation and daytime warming, wet slides and gliding avalanches are possible, more than anywhere else on the northern flank of the Alps and on very steep, sunny slopes.
In the southern regions there is unusually little snow on the ground, at numerous measurement stations less than has ever before been measured at this juncture of the season. As a consequence of the shallow, often expansively metamorphosed (faceted) snowpack there is currently heightened danger of falling into crevices on the glaciers, most particularly in the southern Valais and in southern Grisons.
Observed weather on Friday, 11.03.2022
In the eastern regions it was predominantly sunny. In the western regions heavy cirrus clouds were increasingly prevalent. In the southern regions skies were predominantly overcast, but it remained dry.
Fresh snow
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Temperature
At midday at 2000 m, between +2 °C in the northern regions and -6 °C in the southern regions.
Wind
  • Winds on the northern Alpine Ridge and in Grisons were blowing at moderate strength, intermittently at strong velocity, from southerly directions;
  • in the Alpine valleys of the north, a moderate to strong-velocity foehn wind was blowing.
Weather forecast through Saturday, 12.03.2022
On Friday night in the northern regions, predominantly high-altitude cloud cover is expected. In the southern region a small amount of snowfall is anticipated which will extend down to low lying areas. During the daytime on Saturday it will be predominantly sunny in the eastern regions, in the western regions rather sunny. In the southern regions, skies will bright up incrementally.
Fresh snow
In the Valais section of the Main Alpine Ridge and in the central sector of the southern flank of the Alps, a few centimetres of fresh snow is expected.
Temperature
At midday at 2000 m, between +1 °C in the northern regions and -7 °C in the southern regions.
Wind
  • Winds on the northern Alpine Ridge and on the Main Alpine Ridge will be blowing at moderate strength, intermittently at strong velocity, from southerly directions;
  • in the foehn-exposed regions of the North, a southerly foehn wind will be blowing intermittently at strong velocity.
Outlook through Monday, 14.03.2022
On Sunday in the eastern regions it will be predominantly sunny. In the western and the southern regions skies are expected to be partly overcast. In the Jura region and in the Valais section of the Main Alpine Ridge, a few centimetres of fresh snow could fall.
On Sunday night in the western and the southern regions, a small amount of fresh snow is possible. During the daytime on Monday in the northern regions it is expected to be quite sunny; in the southern regions it will become increasingly sunny.
On both days, a moderate-strength southwesterly wind will be blowing at high altitudes; in the Alpine valleys there will be foehn wind on Sunday in particular. The avalanche situation is not expected to change significantly. In the foehn-exposed regions and at high altitudes, the freshly generated snowdrift accumulations deserve special caution. These drifted masses are frequently prone to triggering, particularly on north-facing slopes. Isolated avalanche prone locations in the old snow occur particularly on very steep, shady slopes in the inneralpine regions.
North of an imaginary Rhine-Rhone line, more than anywhere else, gliding avalanches are possible.