Avalanche Information

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North American Avalanche Rating Scales

 

LOW (green). Natural avalanches very unlikely. Human triggered avalanches unlikely. Generally stable snow. Isolated areas of instability. Travel is generally safe. Normal caution is advised.

 

MODERATE (yellow). Natural avalanches unlikely. Human triggered avalanches possible. Unstable slabs possible on steep terrain.Use caution in steeper terrain on certain aspects (defined in accompanying statement).

         

CONSIDERABLE (orange). Natural avalanches possible. Human triggered avalanches probable. Unstable slabs probable on steep terrain.Be increasingly cautious in steeper terrain.

 

HIGH (red). Natural and human triggered avalanches likely. Unstable slabs likely on a variety of aspects and slope angles. Travel in avalanche terrain is not recommended. Safest travel on windward ridges of lower angle slopes without steeper terrain above.

 

EXTREME (black). Widespread natural or human triggered avalanches certain. Extremely unstable slabs certain on most aspects and slope angles. Large, destructive avalanches possible. Travel in avalanche terrain should be avoided and travel confined to low angle terrain well away from avalanche path run-outs.