Information regarding summer mountain conditions can be found on the Mountain Conditions Report, published by the Association of Canadian Mountain Guides.
When the sun comes out, temperatures go above freezing, or rain occurs, expect wet avalanches. This is especially relevant in steep, high consequence terrain, such as gully's on Mt Andromeda, Mt Edith Cavell, and Mt Wooly/Diadem.
Give large cornices a wide buffer and do not approach the edge or spend time below. They can extend and fail further back than you expect. They tend to get weaker depending on the heat of the day but no guarantees.
New Alpine snow can rapidly develop into a wind slab problem at any time of the year. Avalanches of this nature have occurred on the ramp route and Silverhorn of Mt Athabasca plus other high peaks in the area.
Deep persistent slabs are best managed by:
Cornices are best managed by:
The mountain weather forecast is a good source for detailed weather (https://www.avalanche.ca/weather/forecast) . Other sites include Environment Canada, Mountain Weather, and Spot.
Generally, danger increases with daytime warming and decreases with cold nights particularly if it freezes. Snow bridges over crevasses weaken as the snow thins through the summer thus use extra caution when crossing glaciers. Be vigilant for newly formed windslabs and increasing natural avalanche activity.
Activity increases with rising temperatures especially during warm and sunny afternoons. Use caution if the surface has not frozen overnight. Watch for wind slabs in the alpine particularly following fresh snowfall forming above pre-existing crusts. Cornices can be large and dangerous if you get too close to the edge thus avoidance is key.