Danger Level Probability Distribution Travel
Low
Natural avalanches very unlikely.
Human triggered avalanches unlikely.
Generally stable snow.
Isolated areas of instability.
Travel is generally safe.
Normal caution advised.
Moderate
Natural avalanches unlikely.
Human triggered avalanches possible.
Unstable slabs possible on steep terrain.
Use caution in steeper terrain.
Considerable
Natural avalanches possible.
Human triggered avalanches probable.
Unstable slabs probable on steep terrain.
Be increasingly cautious in steeper terrain.
High
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
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.


Avalanche Safety Basics
Avalanches don't happen by accident, and most human involvement is a matter of choice, not chance. Most avalanche accidents are caused by slab avalanches which are triggered by the victim or a member of the victim's party. However, any avalanche may cause injury or death and even small slides may be dangerous. Hence, always practice safe route finding skills, be aware of changing conditions, and carry avalanche rescue gear. Learn and apply avalanche terrain analysis and snow stability evaluation techniques to help minimize your risk. Remember that avalanche danger rating levels are only general guidelines. Distinctions between geographic areas, elevations, slope aspects and slope angles are approximate and transition zones between dangers exist. No matter what the current avalanche danger there are avalanche-safe areas in the mountains.




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