The pronounced drop in temperatures following the last few days of extremely mild temperatures is having a favourable effect on the snowpack. The layers of snow nearest to the surface are becoming firmer, particularly in the western and the northern regions below approximtely 2000 to 2400 m. At high altitudes the snowpack manifests striking effects of wind impact.
From the southern Valais over the northern Ticino as far as Grisons, there are weak layers evident inside the snowpack. Avalanches can be triggered in these more deeply embedded layers of the snowpack, particularly on seldom-frequented slopes of west-facing, north-facing and east-facing slopes. In isolated cases, avalanches can then grow to large size.

During the nocturnal hours and in the morning in the western and the northern regions there was a small amount of precipitation registered. The snowfall level descended swiftly down to low lying areas. During the daytime from the Valais over the Ticino as far as southern Grisons it was quite sunny. In the northern regions skies remained predominantly overcast, accompanied by some bright intervals during the afternoon.

Between Friday afternoon and Saturday midday the following amounts of fresh snow were registered above approximately 1500 m:

• central and eastern sectors of the northern flank of the Alps: 15 to 30 cm;
• Lower Valais, western sector of the northern flank of the Alps: 5 to 15 cm;
• in the other regions of Switzerland, only a few centimetres; or else, it remained dry.

At midday at 2000 m, between -6 °C in the northern regions and -1 °C in the southern regions.

Winds were blowing from westerly directions, also at strong velocity during the nighttime hours and in general at high altitudes, during the daytime hours predominantly at light to moderate strength.

During the latter part of the night, cloud cover will rapidly move in from the northwest and a small amount of snowfall is anticipated. The snowfall level is expected to ascend to approximately 1000 m. During the daytime in the northern regions, skies will be predominantly overcast. On the southern flank of the Alps it will be quite sunny.

By Sunday midday, the following amounts of fresh snow are expected above approximately 1000 m:

• northern flank of the Alps from the eastern Bernese Oberland as far as the Alpstein: 5 to 10 cm;
• in the other regions of Switzerland, only a few centimetres; or else, it will remain dry.

At midday at 2000 m, -2 °C.

• Winds at high altitudes will be blowing at strong velocity from northwesterly directions;
• winds in the Prealps will be blowing at moderate to strong velocity from southwesterly directions.
  

In the northern regions skies will be heavily overcast on both days. Snowfall is expected down to low lying areas, the snowfall will be persistent and intensive between Monday morning and Tuesday morning. By Tuesday evening in the Lower Valais, on the northern flank of the Alps and in northern Grisons, approximately 40 to 60 cm of fresh snow is possible, from the Bernese Oberland into the Glarus Alps as much as 80 cm of fresh fallen snow. The winds will be blowing at strong velocity from westerly to northwesterly directions. The avalanche danger levels will increase over widespread areas, on Tuesday in the northern regions even Danger Level 4 could be reached in certain regions.
On the southern flank of the Alps it will be sunny on both days. The avalanche danger levels are not expected to change significantly.