Avalanche Warning Levels
Danger Level
|
Icons
|
Snowpack Stability
|
Avalanche Triggering Probability
|
1. Low
|
 |
The snowpack is well bonded and stable in general
|
Triggering is generally possible only from high additional loads** in isolated areas of very steep, extreme terrain. Only sluffs and small-sized natural avalanches are possible
|
2. Moderate
|
 |
The snowpack is only moderately well bonded on some steep slopes*, otherwise well bonded in general
|
Triggering is possible primarily from high additional loads**, particularly on the indicated steep slopes*. Large-sized natural avalanches are unlikely
|
3. Considerable
|
 |
The snowpack is moderately to poorly bonded on many steep slopes*
|
Triggering is possible, even from low additional loads** particularly on the indicated steep slopes*. In some cases medium-sized, in isolated cases large-sized natural avalanches are possible
|
4. High
|
 |
The snowpack is poorly bonded on most steeps slopes
|
Triggering is likely even from low additional loads** on many steep slopes. In some cases, numerous medium-sized and often large-sized natural avalanches can be expected
|
5. Very High
|
 |
The snowpack is poorly bonded and largely unstable in general
|
Numerous large-sized and often very large-sized natural avalanches can be expected, even in moderately steep terrain
|
* Avalanche bulletins describe in great detail avalanche-prone locations (type of terrain, altitude, slope aspect, proximity to ridge, smoothness of underlying ground surface..)
• Moderately steep terrain: slopes shallower than 30 degrees
• Steep slope: slopes steeper than 30 degrees
• Very steep terrain: more than 40 degrees
** Additional loads:
Low:
• Individual skier or snowboarder, riding softly and not falling
• Group keeping distances with spacing over 10m
High:
• 2 or more skiers, snowboarders, etc. not keeping distances
• Single climber/hiker
• Snowmachine
• Explosives
13 January 2016 Author Paul Quigley