Zervreila

Weakly bonded old snow and gliding snow require caution

Weakly bonded old snow and gliding snow require caution

The somewhat older wind slabs are in some cases still prone to triggering. They are to be evaluated with care and prudence. Avalanches can in isolated cases penetrate deep layers and reach medium size. Careful route selection is recommended. In particular on very steep sunny slopes mostly small moist snow slides and avalanches are possible.

Weak layers exist near the base of the snowpack in particular on west, north and east facing slopes above approximately 2200 m. In western Lower Valais and on the northern flank of the Alps, the weak old snow is mostly embedded so deep that the probability of avalanches being released by people is rather small. From central Valais through Ticino to Grisons and generally in places with shallow snow cover, the bonding of the snowpack is least favourable, and people can still release avalanches in the old snowpack. In addition, in particular on the main Alpine ridge, last weekend’s snow drift accumulations remain prone to triggering in some places. Gliding avalanche activity is high, and further gliding avalanches are to be expected in the coming days as well. They can be released at any time of day or night. In the western and northern regions with a lot of snow, these can reach a large size in some cases. On steep south facing slopes, the surface of the snowpack will become moist because of its exposure to warming and radiation during the day. Here, the mostly clear skies on Tuesday night will give rise to a melt-freeze crust on the surface of the snowpack.

On Tuesday in the mountains it was mostly sunny, with cloudbanks in the southeast in particular. Fresh snow: - Temperature: At midday at 2000 m: between +6 °C in the west and +4 °C in the east, and about +7 °C in the south; the zero degree level rose to approximately 2800 m Wind: Light to moderate from the north to northeast The night will be partly clear with cloudbanks. During the day in the mountains it will be mostly sunny, and at elevated altitudes it will become a little warmer. Fresh snow: - Temperature: - At midday at 2000 m: between +6 °C in the west and +3 °C in the east - In the afternoon the zero degree level will rise to altitudes between approximately 3500 m in the west and 3000 m in the southeast Wind: During the night on Alpine ridgelines, moderate, otherwise light to moderate, from the north to northeast

In the mountains each of the coming days will be mostly sunny and mild. The wind will be mostly moderate from the north to northeast. The danger of dry avalanches will decrease slowly. The danger of gliding avalanches will persist. In the regions with a lot of snow, gliding avalanches can reach a large size in some instances. The danger of moist avalanches will increase during each of the coming days on very steep sunny slopes.