The avalanche danger is variable and can range from Low to High. Travelling early in the day is recommended, as conditions can change rapidly in short periods of time due to daytime warming. Pay careful attention to the integrity of surface crusts formed overnight and rising air temperatures during the day. Dry slab avalanche danger may also exist during spring snow storms.
When the sun comes out, temperatures soar above freezing, or rain falls, expect Wet Loose avalanches and Cornice failures. This is especially relevant in steep, high consequence terrain, such as gully climbs on Mt. Andromeda and Mt. Edith Cavell.
Crusts and facets from the long winter persist. These could remain active in the alpine into the Summer season, waking up with rising temperatures or Cornice falls. Watch for slabs on large alpine features, such as the Ramp on Mt. Athabasca.
Any new snow falling high in the Alpine can quickly become Wind Slabs at any time of the year. This has been a problem in the past on terrain like the Silverhorn and Ramp routes on Mt. Athabasca, and on other high peaks, such as Mt. Columbia.
Deep persistent slabs are best managed by:
Cornices are best managed by:
The Mountain Weather Forecast is available from Avalanche Canada (https://www.avalanche.ca/weather/forecast).
Detailed local forecasts are available from sites like SpotWX (https://spotwx.com/)
An overview is available: (https://www.avalanche.ca/pages/static-page/spring-conditions)
Generally, danger increases with daytime warming, & decreases with cold, clear nights. A winter snowpack may persist on shaded, high alpine slopes.
As the snow thins, crevasse bridges weaken. Use extra care in thin wind-affected areas, eg the Athabasca Glacier.
Expect activity with rising temps, especially during warm and/or sunny afternoons. Use extra caution if the surface didn't freeze overnight.
Watch for Wind Slabs in the alpine, particularly following snow or rain at lower elevations. Use extra caution if they form above crusts, which can happen well into summer on high peaks, eg Mt Athabasca.