This site provides maps that delineate the location and text that provide a brief description of avalanche hazards that could impact the maintained winter trail system in Western Wyoming. These trails have been designed to avoid most avalanche prone terrain, however in some places they cross beneath known avalanche paths, steep hillsides and/or steep banks that sometimes avalanche.
Most avalanches occur during and immediately after storms, especially those accompanied by high winds and/or extended periods of intense snowfall. Rapid warming and rain on snow events are also red flags for avalanche activity. The following web sites are excellent sources of information for people who travel in avalanche terrain.
Avalanche Basics -US Forest Service, National Avalanche Center
Online Avalanche Class - Teton Gravity Research
The Avalanche Encyclopedia - National Avalanche Center and The Friends of the Utah Avalanche Forecast Center
Daily avalanche hazard advisories are issued for the mountainous areas of Western Wyoming by the Bridger-Teton National Forest Avalanche Center at jhavalanche.org. These advisories are posted twice daily from early November to mid April.
Trail Avalanche Hazard Ratings
This project has mapped the potential hazard to trails using the following color scheme. These ratings only apply to the immediate area of the groomed or maintained trails. In some areas dangerous slopes exist immediately adjacent to safe sections of this trail system.
Black - Sections of the trail system where avalanche are not expected .
SOME HAZARD - Sections of the trail system where dangerous avalanches are possible.
GREATER HAZARD - Sections of the trail system where dangerous avalanches occur on a more frequent basis or where infrequent avalanches with very serious consequences are possible.
Avalanche Hazard Features
Major Slidepath - Generally larger steep topographic features that can avalanche across a section of the trail system
Minor Slidepath - Generally smaller topographic features such as open hillsides and steep banks that can avalanche onto or across a section of the trail system.
Terrain Traps are topographic features that could cause a small volume of avalanche debris to accumulate to significant depths or dangerous features that could harm a person who was swept into or over them. Examples are creek bottoms, v-shaped gullies, cliffs, trees and rocky areas.