On Sunday night, a wintery storm will set in, bringing heavy precipitation. The storm is expected to transport the fresh fallen snow and old snow intensively. In zones distant from ridgelines, deep snowdrift accumulations will be generated in places. More deeply embedded inside the snowpack, particularly on west-facing, north-facing and east-facing slopes, pronounced weak layers are evident. On the northern flank of the Alps, these weak layers are generally blanketed over by thick layers.From the southern Valais over the northern Ticino as far as Grisons, the entire old snowpack is expansively metamorphosed in numerous areas. The old snowpack, particularly in the inneralpine regions, is prone to triggering. On the weekend, numerous large-sized avalanches were triggered by persons in those regions, in isolated cases the releases were very-large sized.

In the Jura region skies were predominantly overcast, but it remained largely dry until afternoon. In the other regions of Switzerland it was initially quite sunny, accompanied by cloudbanks, but skies become increasingly overcast from the northwest during the course of the day.

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At midday at 2000 m, between -3 °C in the northern regions and -1 °C in the southern regions.

Winds were westerly to southwesterly,

• on Saturday night and during the daytime on Sunday, also in the Ticino and in Grisons, blowing at light to moderate strength;
• intensifying in the course of the day, as well as in the western and the northern regions blowing at moderate to strong velocity.

On Sunday night, heavy precipitation is expected to set in. Accompanied by storm-strength westerly to northwesterly winds, the precipitation will extend far into the southern regions. Only in Sotto Ceneri will it remain dry. Initially the snowfall level will ascend for a brief spell from 800 m to approximately 1400 m. Subsequently during the course of the night, the snowfall level will again descend to approximately 600 m. During the daytime on Monday, skies will be heavily overcast to begin with, the snowfall will slacken off from the west. In the western and the southern regions it will be partly sunny in the afternoon.

Between Sunday afternoon and Monday afternoon, the following amounts of fresh snow are anticipated above 1600 m:

• northern Alpine Ridge, Valais not including Saastal and also not including the southern Simplon region, northern Grisons, Silvretta, Samnaun: 30 to 50 cm;
• Jura region, remaining regions of the northern flank of the Alps, Saastal, southern Simplon region, and the remaining parts of the Gotthard region, central Grisons, remaining parts of Lower Engadine: 20 to 40 cm;
• further to the south: 5 to 20 cm; in the Sotto Ceneri it will remain dry.

Due to storm-strength winds the fresh fallen snow will be distributed and deposited in highly irregular fashion.

Temperatures will drop. At midday at 2000 m: -9 °C in the northern regions and -6 °C in the southern regions.

• Winds will be blowing from westerly to southwesterly directions to start with, subsequently on Sunday night shifting to northwesterly and blowing at strong to storm-strength. Strong storm winds will be blowing in high alpine regions.
• In the southern regions, strong to storm-strength northerly winds extending down to low lying areas.