Avalanche Forecast
Regions: Banff, Banff Yoho Kootenay, East Side 93N, Field, Kootenay, LLSA, Lake Louise, Little Yoho, Sunshine, West Side 93N.
Small amounts of new snow combined with moderate westerly winds on Wednesday may form small wind slabs. While not listed as a problem, be mindful of fresh wind slabs developing at the local level.
Confidence
Moderate
Avalanche Summary
The Parks Canada field team observed loose dry avalanches in the Surprise Pass area up to size 1 out of extreme terrain, some running far on shaded aspects. Sunshine patrol reported one small windslab about 20cm deep outside of the boundary.
Snowpack Summary
There's 10 cm of storm snow sitting on the March 2 crust, which rests on a cohesive slab. Below that are the February 22 and January 30 weak layers, followed by a faceted mid-pack and basal facets at the bottom. The snowpack is structurally weak, even when it seems stable—don’t overthink it. Focus on terrain choice and group management.
Weather Summary
Expect 3 to 5 cm of snow early Wednesday, with cloudy conditions throughout the period. Temperatures will remain seasonal, staying just below zero in the valley and dropping to -10°C or colder at the ridge, with the freezing level expected to stay below the surface. Moderate westerly winds overnight will ease to light by midday.
Terrain and Travel Advice
- Keep in mind that human triggering may persist as natural avalanches taper off.
Avalanche Problems
Persistent Slabs
Recently, persistent slabs up to 60cm thick were reactive on 2 different weak layers; natural avalanches were widespread. Now, the wet snow has refrozen and these slabs are less reactive. Triggering remains possible in areas that did not melt/freeze, typically higher elevation polar aspects.
Aspects: North, North East, East, North West.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1.5 - 3