Outgoing longwave radiation during the night will be reduced. As the day progresses a moderate danger of wet and gliding avalanches will prevail
Edition: 28.3.2022, 17:00 / Next update: 29.3.2022, 18:00
Snowpack
Tonight the outgoing longwave radiation will be reduced and the crust will therefore be thinner than on recent days. Warming during the day will thaw the crust quickly and weaken the snowpack. Both wet snow and gliding avalanches can occur. In recent days only a few wet snow avalanches have been reported despite the mild and sunny weather.
In particular in the inneralpine and southern regions of Grisons and in southern Valais, distinct weak layers exist deep in the snowpack. Here, slab avalanches consisting of moist and wet snow can be released in these layers or, in some cases, be triggered by people. Isolated such occurrences have been observed in Grisons in particular.
The snowpack is thoroughly moist on north facing slopes below approximately 1800 m, on east facing slopes below approximately 2500 m, on south facing slopes up to more than 3000 m, and on west facing slopes below approximately 2800 m. Given the persistence of dry weather conditions, however, only very little melt water is penetrating the snowpack.
In general, the quantity of snow lying on the ground is small; exceptionally little snow is lying in the south. In view of the thin and in many cases faceted snowpack, on glaciers there remains an elevated risk of falling into a crevasse, especially in southern Valais.
Observed weather on Monday, 28.03.2022
After a clear night, the day was sunny.
Fresh snow
-
Temperature
At midday at 2000 m: between +6 °C in the west and south, and +4 °C in the east
Wind
Light to moderate from southerly directions
Weather forecast through Tuesday, 29.03.2022
As high-altitude cloud develops and the skies become overcast because of Saharan dust, the outgoing longwave radiation will be reduced during Monday night. In the morning, but for some high-altitude cloud and the Saharan dust, it will remain partly sunny, in particular in the east and south. In the afternoon the cloud will become more dense, and light precipitation will arrive from the west; above approximately 1800 m it will fall as snow.
Fresh snow
In the afternoon in the west and north a few centimetres of snow may fall above 1800 m.
Temperature
At midday at 2000 m: about +4 °C in the north and +2 °C in the south
Wind
Light to moderate from southwesterly directions
Outlook through Thursday, 31.03.2022
It will be mostly very cloudy and a little snow will fall at times. This applies to the south and west in particular on Wednesday and to the north in particular on Thursday. In two days around 10 to 20 cm of snow could fall, and even as much as 30 cm in the north. The wind will be mostly light to moderate, from the southwest on Wednesday and from northerly directions on Thursday. The snowfall level will slowly drop towards 1000 m in the north; it will be approximately 1400 to 1700 m in the south.
The danger of dry avalanches will increase slightly; small snow drift accumulations will form. The danger of wet snow avalanches will decrease. Individual gliding avalanches can still occur, in particular on the northern Alpine ridge.