Wet snow
- All elevations
In the west and in the north intensive rain below approximately 2800 m. High avalanche danger will be encountered in some regions.
Snowpack
Valais and northern flank of the Alps: as a consequence of persistent rounds of snowfall, the critical amount of fresh fallen snow has been exceeded over widespread areas at high altitudes. As a result of rainfall up to approximately 2800 m, a renewed increase of naturally triggered avalanche activity can be expected. In the regions of the western and northern Lower Valais more than anywhere else, where there has been major snowfall, the large amounts of old snow can be swept along in avalanches which trigger and very large-sized avalanches can then be expected. In the central and eastern sectors of the northern flank of the Alps, avalanches are expected to be of lesser magnitude due to the smaller amounts of snow on the ground prior to the current bouts of precipitation. Below approximately 2600 m, the snowpack is becoming thoroughly wet as a consequence of intensive rainfall, and a great many wet-snow and gliding avalanches can be expected, including dangerously large triggerings. Ticino, Grisons: In these regions, the increase in the number of avalanche prone locations at heightened altitudes is striking. As a result of more snowfall and, particularly at elevated altitudes, persistent snow transport, significantly more numerous avalanche prone locations exist above approximately 2500 m than below that altitude. Below approximately 2400 m, the snow cover is moist and increasingly frequent wet-snow slides and gliding avalanches can be expected.
Weather forecast through Tuesday, 14.11.2023
Only in the furthermost southern regions are bright intervals to be expected, in the remaining regions of Switzerland skies will be predominantly overcast. In the western and the northern regions, intensive precipitation can be expected intermittently. The snowfall level will lie at approximately 2800 m for an extended time. Only starting in the afternoon will the snowfall level gradually descend down to nearly 2000 m.
Fresh snow
Between Monday midday and Tuesday midday, the following amounts of fresh snow are anticipated in the high alpine regions, above approximately 2800 m:
In the western part of the Lower Valais and north of an imaginary Rhine-Rhone line, 50 to 80 mm of rainfall is anticipated over widespread areas below 2800 m altitude.
Temperature
At midday at 2000 m, between +6 °C in the western and the southern regions and +3 °C in the northeastern regions.
Wind
Observed weather review Monday, 13.11.2023
Nocturnal skies in the southeastern regions were partly clear, in the other regions of Switzerland skies were overcast. During the daytime hours in the southern regions it was partly sunny, frequently in the northern regions skies were heavily overcast accompanied by some bright intervals during the course of the day. During the nighttime hours more than at any other time, there was precipitation in the northern regions. The snowfall level ascended in the western regions to 2400 to 2600 m, in the eastern regions to approximately 2200 to 2400 m.
Fresh snow
Between Sunday afternoon and Monday afternoon, the following amounts of fresh snow were registered above approximately 2600 m:
Temperature
At midday at 2000 m, between +4 °C in the northern regions and +6 °C in the southern regions.
Wind
Outlook through Thursday, 16.11.2023Wednesday
Temperatures are expected to drop markedly and the snowfall level descend down to approximately 1500 m. In the northern regions, approximately 20 to 40 cm of fresh fallen snow is anticipated. The danger of wet-snow avalanches will decrease significantly. The danger of dry-snow avalanches is expected to remain at critical levels at heightened altitudes in particular. In the southern regions, it is expected to remain predominantly sunny and dry. The avalanche situation is not expected to change significantly.
Thursday
It will remain cold. In the northern regions, skies will be variably cloudy, a small amount of snowfall is possible. Avalanche danger levels are expected to decrease further. In the southern regions it will be predominantly sunny, avalanche danger is not expected to change significantly.
Bulletin data: WSL Institute for Snow and Avalanche Research SLF (CC BY 4.0)