Small Changes to the North American Public Avalanche Danger Scale
2022 updates include new icon and travel advice for the Extreme danger rating.
The North American Public Avalanche Danger Scale (NAPADS) (Statham et al. 2010) is the foundational component of public backcountry avalanche forecasts in North America. The scale consists of an ordinal, five-level system that provides a basic ranking of avalanche danger for a specific region over a period of time. The likelihood, size, and distribution included in NAPADS are derived from the foundational processes described in the Conceptual Model of Avalanche Hazard, or CMAH (Statham et al. 2017). The scale and its components are maintained by a collaborative working group consisting of U.S. and Canadian stakeholders. The current scale was published in 2010 and updated in 2022.