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The new scale is the result of collaboration between avalanche professionals in Canada, the USA and Europe. It is a North American Danger Scale with Icons standardized internationally (recognizable by Europeans visiting Noth America.)
- The danger levels have been reversed — Extreme is now on top.
- Extreme and High have been grouped as backcountry travel is not reccommended at either level.
- Icons have been added to give an at-a-glance indication of the risk of travel.
- Travel advice is given for each danger level.
- The likelyhood of avalanches information has been retained from the previous scale.
- The last column gives the potential size and extent of avalanches.
This is the most difficult danger level for backcountry skiers and boarders to assess snow stability. Many of the usual indicators such as cracks, settling, whumpfing and signs of recent avalanche are absent, especially at the lower end of the moderate level. Key indicators are any recent snowfall, and wind deposition. Snowpack tests may help assess stability.
Conditions have become much less favourable. The snowpack is only moderately or poorly bonded over a much larger area of the terrain. Human triggering is possible by a single skier on steep slopes and aspects mentioned in the Avalanche Forecast. Remote triggering of avalanches is possible, so the maximum steepness of the slope above you should be used when deciding if you want to continue.
Conditions have become dangerous, most often as a result of significant amounts of new snow, snowfall accompanied by wind or the snowpack becoming isothermal and threatening wet-snow avalanches. The snowpack is poorly bonded over large areas and human triggering is likely on steep slopes (steeper than 30°). Remote triggering is likely and large natural avalanches are to be expected.
Extreme danger levels are rare and usually the result of unusually large amounts of new snow. The snowpack is weakly bonded and unstable. Numerous large avalanches are likely. The weight of the new snow can trigger avalanches on layers buried deep in the snowpack. Natural avalanches can release on slopes of less than 30°