Persistent weak layers
- Above 2,000 m
Snowpack
New snow and drifted snow from the past week is lying on pronounced weak layers, especially on wind-protected shady slopes. South of a line from the Rhône to the Rhine, the entire snowpack is often faceted and loose. In addition, with the strong southerly winds at times, some highly visible, prone-to-triggering wind slabs have formed over the past three days. On the southern flank of the Alps, the fresh snow from the weekend was deposited on top of an equally weak snowpack.
It is possible for medium and large-sized avalanches to be triggered in the old snowpack over a wide area. The snowpack on northern and eastern slopes in Valais and northern Grisons is particularly prone to triggering. Avalanches may also be triggered in isolated cases in the old snowpack on the northern flank of the Alps. Remote triggering, sometimes over long distances, is still possible.
Weather forecast to Tuesday
In Ticino and southern Grisons, it will be mostly overcast with some snow at times. Elsewhere it will be mostly sunny.
Fresh snow
Southern Simplon region, Ticino and southern Grisons: up to 5 cm
Temperature
At midday at 2000 m, around 0 °C in the north and -4 °C in the south
Wind
Moderate to strong southerly foehn wind in the north, light to moderate elsewhere
Weather review for Monday
It was mostly cloudy in the south and some snow fell at times on the southern flank of the Alps above approximately 1200 m. In the north, it was quite sunny with foehn winds.
Fresh snow
A few centimetres in the southern Simplon region and in Valle Maggia
Temperature
At midday at 2000 m, between +2 °C in the north and -3 °C in the south
Wind
From southeast to south, easing
Outlook to Thursday
On Wednesday it will be sunny. On Thursday it will be sunny at times in the west and mostly sunny in the east. Winds will mainly be light.
The avalanche danger will continue to decrease slowly. Weak layers in the old snowpack will remain prone to triggering, especially in the inneralpine regions.
Bulletin data: WSL Institute for Snow and Avalanche Research SLF (CC BY 4.0)