| Probability and trigger |
Degree and distribution of danger |
Recommended action in back country |
| Low (green) |
Natural avalanches very unlikely. Human triggered avalanches unlikely. Generally stable snow. Isolated areas of instability. |
Travel is generally safe. Normal caution advised. |
| Moderate (yellow) |
Natural avalanches unlikely. Human triggered avalanches possible. Unstable slabs possible on steep terrain. |
Use caution in steeper terrain. |
| 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 (red/black border) |
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. |