Using stability tests and regional avalanche danger to estimate the local avalanche danger

Because public avalanche forecast regions in Canada are large, ranging from 100 to >30 000 km(2), there are often areas within each region where the current local avalanche danger differs from the forecast regional danger. Identifying areas where the local danger is higher or lower than the regional rating is useful for recreational backcountry travellers; for those with limited experience, however, this is not always practical. During four winters in the Columbia, Coast and Rocky Mountains of western Canada, field teams performed stability tests and undertook local avalanche danger assessments for comparison against the regional danger ratings. Significant correlations between stability test variables and the local avalanche danger, and between stability test variables and the difference between local and regional danger, indicate potential for improved evaluation of the local danger if stability test results are considered with the regional bulletin rating. Although our analysis shows that a single stability test result cannot reliably be used to estimate the local avalanche danger, it does identify circumstances under which stability tests can help backcountry recreationists identify an area of locally higher avalanche danger.