Natural and human-triggered avalanches are unlikely. Unstable slabs are possible on steeper slopes. Natural avalanches are unlikely, but human-triggered avalanches are possible. Caution should be exercised on steep terrain. High probability of unstable slabs on steeper slopes.
Natural avalanches are possible, and human-triggered avalanches are likely.
Caution must be exercised on steep terrain. Unstable slabs are likely on moderate and steep slopes. Natural and human-triggered avalanches are certain. Extreme caution and avalanche awareness skills must be used for safe travel on avalanche terrain. Extremely unstable slabs are certain on most slopes.