New snow
- Todas las altitudes
In the west a high avalanche danger will be encountered in some regions.
The fresh snow and in particular the often large wind slabs are prone to triggering. Even single winter sport participants can release avalanches easily, including dangerously large ones. Whumpfing sounds indicate the danger. Individual medium-sized to large natural avalanches are possible. Backcountry touring and other off-piste activities call for experience in the assessment of avalanche danger and restraint.
Snowpack The often strong wind has transported the fresh snow that has fallen since last weekend. In particular in the eastern part of the northern flank of the Alps and in Grisons, in some localities old snow has been transported as well. Snow drift accumulations that are prone to triggering have formed over a wide area. In the west these accumulations are large. The fresh snow and wind slab layers are settling and bonding only slowly because of the low temperatures. The snow drift accumulations will increase in size a little more on Tuesday night as a consequence of fresh snow and wind. Faceted and loosely bonded weak layers are to be found in deep layers of the snowpack on north facing slopes above 2200 m to 2400 m and on south facing slopes approximately 2800 m. These are prone to triggering in particular in southern Valais and in Grisons. Observed weather review Tuesday, 17.01.2023 On Monday evening more snow than expected fell in western Lower Valais. The snowfall then gradually eased on Monday night. During the day it was very cloudy and, in the west and south in particular, snow fell in showers even at low altitudes. In the northeast it remained dry and, in the afternoon, became increasingly bright. Fresh snow From Monday afternoon until Tuesday afternoon above approximately 1000 m:
Since Saturday afternoon, the following aggregate amounts of snow have fallen above approximately 2000 m:
Temperature At midday at 2000 m: about -6 °C in the west and about -8 °C in the east and south Wind
Weather forecast through Wednesday, 18.01.2023 The north will be very cloudy and snow will fall over a wide area, even at low altitudes. The south will be partly sunny. Fresh snow From Tuesday afternoon until Wednesday afternoon the following amounts of snow will fall above 800 m:
Temperature At 2000 m: about -10 °C in the north and -8 °C in the south Wind
Outlook through Friday, 20.01.2023 In the north on both days it will be cloudy with bright intervals and local snow showers. In Valais and the south it will be partly sunny on Thursday and quite sunny on Friday. As a consequence of the moderate north to northeasterly wind, it will be very cold in the mountains. The avalanche danger will decrease slowly in the north, but not change significantly in the south.
Bulletin data: WSL Institute for Snow and Avalanche Research SLF (CC BY 4.0)