Hasliberg - Rosenlaui

As a consequence of new snow and stormy weather a high avalanche danger will be encountered over a wide area.

Snowpack

With precipitation, wind and the rise in temperature, many naturally triggered avalanches occurred during Saturday night. This could happen again on Monday. At high altitudes, there is about twice as much snow as there normally is at the beginning of December. The snowpack has a favourable structure, apart from thin weak layers of angular crystals deep in the snowpack in the area of older rain crusts. With all the new snow and intense rain, these weak layers could be reactivated in the next few days. In the south, the snow depths are below average and the weak layers are therefore closer to the surface. Especially there, the older weak layers can also be released by people in some cases. In all regions and in all aspects, more gliding avalanches are expected below about 2400 m on slippery ground.

Weather forecast through Monday, 11.12.2023

It will be very cloudy with precipitation, with heavy precipitation in the west and north. In the far west and north, the snowfall level will increase temporarily to around 2200 to 2500 m on Sunday evening and then fall to around 2000 m. In the southeast, it will lie between 1500 and 2000 m.

Fresh snow

Until Monday afternoon, above approximately 2500 m:

• northern Alpine Ridge, Lower Valais and Visp valleys: 40 to 70 cm;
• other parts of Valais and the Gotthard region, highest peaks north of the northern Alpine Ridge and from Prättigau to Samnaun: 20 to 40 cm;
• elsewhere: to a lesser extent.

There will be a lot of rain at lower altitudes and also in the Jura.

Temperature

At midday at 2000 m, between +3 °C in the northwest and +1 °C in the southeast.

Wind

There will be strong to locally stormy winds on the northern flank of the Alps and generally at high altitudes, otherwise there will be a moderate westerly wind.

Observed weather review Sunday, 10.12.2023

Precipitation fell during Saturday night, with intense rain in the west and north. In the north, the snowfall level rose temporarily to around 2000 m on Saturday evening, otherwise it was around 1200 to 1600 m. During the day it became dry and there were brighter spells in the west and south.

Fresh snow

From Saturday to Sunday afternoon, the following levels were recorded above approximately 2400 m:

• northern Alpine Ridge, extreme west of Lower Valais: 30 to 40 cm;
• other parts of Valais, the Gotthard region and northern Grisons, highest peaks north of the northern Alpine Ridge, Samnaun: 20 to 30 cm;
• elsewhere: to a lesser extent.

Temperature

At midday at 2000 m, between -4 °C in the north and -1 °C in the south.

Wind

• There were strong and locally stormy winds from the west.
• There was a moderate to strong wind from the northwest during the day on the main Alpine Ridge and in the south.

Outlook through Wednesday, 13.12.2023

It will be very cloudy with continued heavy precipitation in the west and north. The snowfall level will initially be around 2200 m in the west and 1800 m in the east. On Wednesday, it will drop to around 1300 m everywhere. From Monday to Wednesday afternoon, a further 40 to 70 cm of snow will fall above approximately 2500 m on the northern Alpine Ridge and in the extreme west of Lower Valais, 20 to 40 cm in the rest of Valais and from northern Prättigau to Samnaun, and less elsewhere. Tuesday will see frequent, strong westerly winds, with moderate winds on Wednesday. On the northern Alpine Ridge and in Valais, the danger will increase slightly on Tuesday within level 4 (high). It will not change significantly on Wednesday. Below 2000 to 2400 m, some large, wet avalanches are expected. Dry avalanches are expected from starting zones at higher altitudes, which will sweep along the increasingly saturated old snowpack in their path and advance into the valleys in the usual avalanche tracks. These avalanches can become very large and exposed parts of transportation routes are at risk. The conditions will be dangerous for winter sports outside marked and open pistes. In the other regions of Grisons, the avalanche danger will also increase slightly, but will not change significantly in the far south.