Home  |  About Us  |  Contact Us


Avalanche Terrain Ratings

Class 1 - Simple

Exposure to low angle or primarily forested terrain. Some forest openings may involve the runout zones of infrequent avalanches. Many options to reduce or eliminate exposure.

Class 2 - Challenging

Exposure to well defined avalanche paths, starting zones or terrain traps; options exist to reduce or eliminate exposure with careful route finding. Glacier travel is straightforward but crevasse hazard may exist.

Class 3 - Complex

Exposure to multiple overlapping avalanche paths or large expanses of steep, open terrain; multiple avalanche starting zones or terrain traps below; minimal options to reduce exposure. Complicated glacier travel with extensive crevasse bands or icefalls.


Decision Point
Weather Station


Check/Uncheck to Show/Hide each zone. Click to Zoom to that zone. Reset Map
White Pass West
White Pass East
Haines Pass
Montana Mountain
Powder Valley
Tutshi Chutes
Wheaton Valley
Print Map


A major component of pre-trip preparation is information gathering. One of the best ways to avoid getting caught in an avalanche is to choose routes that are appropriate for the conditions. Chose an appropriate route based on its exposure to avalanche terrain. These areas have been rated according to the Avalanche Terrain Exposure Scale.

The online Trip Planner has an embedded Google Maps interactive interface. Left click on the coloured polygon. The ATES attributes come up - those that are highlighted are the attributes applicable to the area that led the classification decision. Left click on the Snowflake icon for a destination and a summary of cautions and mitigation measures will come up.

Any given piece of mountain terrain may have elements that will fit into multiple classes. Applying a terrain exposure rating involves considering all of the variables on the matrix with some default priorities.

The ATES classification is a function of scale and zoom limitation is set to ensure it is not interpreted at a fine scale. ATES zoning maps are not intended for route finding, more for pre-trip planning.

Planning a trip? See the Pre-Trip Planning on the Canadian Avalanche Centre website.


White Pass Trailhead Sign

Haines Pass Trailhead Sign

Tombstone Territorial Park Trailhead Sign

White Pass ATES Brochure (7.1MB)

Haines Summit ATES Brochure (2.8MB)