Avalanche International Danger Scale

Low 1: Natural avalanches very unlikely. Human triggered avalanches unlikely. Travel is generally safe. Normal caution advised.

Moderate 2: Natural avalanches unlikely. Human triggered avalanches possible. Use caution in steeper terrain on certain aspects.

Considerable 3: Natural avalanches possible. Human triggered avalanches probable. Be increasingly cautious in steeper terrain.

High 4: Natural and human triggered avalanches likely. Travel in avalanche terrain is not recommended.

Extreme 5: Widespread natural or human triggered avalanches certain. Travel in avalanche terrain should be avoided and confined to low angle terrain, well away from avalanche path runouts.