Valgrisenche

From starting zones at higher altitudes large avalanches are to be expected.

From starting zones at higher altitudes large avalanches are to be expected.

As a consequence of rising temperatures, solar radiation and the occasionally moderate wind, a very critical avalanche situation will develop on Friday. In starting zones where no previous releases have taken place natural avalanches, capable of reaching low altitudes, must be expected, especially above approximately 2500 m. In particular on shady slopes the avalanches can be triggered in deep layers of the snowpack. The weather conditions gave rise to rapid moistening of the snowpack over a wide area below approximately 2900 m. Moist avalanches can in some places be released in the weakly bonded old snow. The backcountry touring conditions remain very critical.

80 to 130 cm of snow has fallen since Tuesday above approximately 2500 m. Since Thursday the wind has been moderate in some localities. The weather conditions on Thursday gave rise to moistening of the snowpack over a wide area below approximately 2800 m. The sleet gave rise to thorough wetting of the snowpack in all aspects below approximately 2400 m. The night between Thursday and Friday will be clear: the snow on the surface will be able to refreeze. Since Wednesday numerous large avalanches occurred naturally.

Gradual decrease in danger of dry avalanches. On Saturday the likelihood of moist and wet avalanches being released will increase in particular below approximately 3000 m.