Moderate avalanche danger will be encountered over a wide area
Edition: 25.3.2021, 17:00 / Next update: 26.3.2021, 18:00
Snowpack
Particularly in the Valais south of the Rhone, in Grisons south of the Anterior Rhine and in the Gotthard region, the uppermost layers of the snowpack are marked by a weak layer over widespread areas. In this layer, isolated avalanches have been triggered by persons on west-facing, north-facing and east-facing slopes during the last few days. Avalanches fractured down to more deeply embedded, even to ground-level layers of the old snowpack in isolated cases, in places where the snow was shallow more than anywhere else.
Also in the remaining regions of Switzerland, this weak layer on shady slopes is evident in some places. Avalanche triggerings in this layer have been reported only in isolated cases. During nights of clear skies, the snowpack surface can freeze down to intermediate altitudes. As a result of the daytime warming and solar radiation, the danger of wet-snow and gliding avalanches increases on sun-drenched slopes during the course of the day.
Observed weather on Thursday, 25.03.2021
Nighttime skies were clear. During the daytime it was quite sunny in spite of high-altitude cloudbanks. During the afternoon convective cloud build-up was evident in the western regions.
Fresh snow
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Temperature
At midday at 2000 m, +1 °C in the northern regions and +3 °C in the southern regions.
Wind
During the nocturnal hours winds were intermittently blowing at moderate strength from northerly directions; during the daytime, predominantly light winds from the west prevailed.
Weather forecast through Friday, 26.03.2021
Nighttime skies will be predominantly clear. During the morning hours it will be quite sunny to start with, subsequently cloud cover will move in from the west and the south. However, it is expected to remain dry.
Fresh snow
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Temperature
At midday at 2000 m, between +3 °C in the northern regions and +1 °C in the southern regions.
Wind
During the night, predominantly light southwesterly winds are anticipated, intensifying during the course of the day, then blowing at moderate to strong velocity in the afternoon in the western regions, in the foehn-exposed regions and in general in the high alpine regions.
Outlook through Sunday, 28.03.2021
Saturday
Precipitation is anticipated over widespread areas during the night. The snowfall level will descend from 1800 m down to nearly 1000 m. On Saturday, it will become increasingly sunny from the west.
Avalanche danger levels are expected to increase somewhat over widespread areas as a result of fresh snowfall and moderate-to-strong velocity southwesterly winds at high altitudes.
Sunday
It is expected to be predominantly sunny.
The danger of dry-snow avalanches is not expected to change significantly. As a result of daytime warming and solar radiation, wet-snow and gliding avalanches will be possible during the course of the day.