Avalanches may release spontaneously on some steep slopes. Avalanches can get large enough to bury or even kill you (size 2).
You can trigger avalanches on a few steep slopes. Avalanches can get large enough to bury a car or destroy a small house (size 3).
Avalanches may release spontaneously on a few steep slopes. Avalanches are relatively harmless to people, but can knock you off balance. Can be dangerous close to terrain traps. (size 1)