At elevated altitudes a considerable avalanche danger will be encountered in some regions
Edition: 24.3.2021, 17:00 / Next update: 25.3.2021, 18:00
Snowpack
Particularly south of an imaginary Rhine-Rhone line, a markedly weak layer is evident in the uppermost layers of the snowpack in the Valais and in Grisons, as well as in the Gotthard region. In this weak layer there have been repeated avalanches triggered by persons over the last few days, often of dangerously-large size. In places where the snow is shallow more than anywhere else, isolated avalanches have fractured down to ground-level layers of the old snowpack. Also in the other regions of Switzerland, this weak layer is evident in some places on shady slopes. However, avalanche triggerings have been registered only in isolated cases in this layer.
In addition, snowdrift accumulations which in the interim are somewhat older are also prone to triggering in some places at high altitudes, particularly on shady slopes.
As a result of the increasing degree of snowpack wetness, the danger of wet-snow and gliding avalanches on sun-drenched slopes will increase during the course of the day.
Observed weather on Wednesday, 24.03.2021
Following a night of clear skies it was sunny during the daytime.
Fresh snow
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Temperature
At midday at 2000 m, between +2 °C in the western and the southern regions and 0 °C in the eastern regions.
Wind
Winds on the Main Alpine Ridge will be blowing intermittently at moderate strength from northerly directions, otherwise predominantly at light strength.
Weather forecast through Thursday, 25.03.2021
Nocturnal skies will be clear. During the daytime it will be quite sunny for short periods, accompanied by high-altitude cloudbanks. During the afternoon, convective cloud build-up is anticipated. Local showers cannot be ruled out from place to place.
Fresh snow
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Temperature
At midday at 2000 m: 0 °C in the northern regions and +2 °C in the southern regions.
Wind
Winds during the nighttime hours will shift from northerly to westerly-to-southwesterly, on the southern flank of the Alps and in the high-alpine regions blowing intermittently at moderate strength, otherwise predominantly at light strength.
Outlook through Saturday, 27.03.2021
Friday
During the course of the day, clouds will move in from the southwest. However it will remain dry. The southwesterly winds will intensify during the course of the day.
The danger of dry-snow avalanches is expected to decrease still further. The danger of wet-snow and gliding avalanches will be subject to daytime fluctuations, i.e. a daytime cycle.
Saturday
On Friday night and during the daytime on Saturday, a small amount of precipitation is anticipated over widespread areas. The snowfall level will descend from 1700 m down to nearly 1000 m. However, the amounts of precipitation are still uncertain.
Avalanche danger could íncrease somewhat at high altitudes as a result of fresh fallen snow.