Avalanche Forecast
Regions: Banff, Banff Yoho Kootenay, East Side 93N, Field, Kootenay, LLSA, Lake Louise, Sunshine, West Side 93N.
Monday looks like a great time to be up high but watch for the effects of solar warming later in the day. Ski quality varies from poor in wind-exposed areas to good in sheltered spots. Be cautious of lingering wind slabs, and continued facetting of the surface snow, which may sluff easily in extreme terrain.
Confidence
High
Avalanche Summary
On Saturday local ski hills reported triggering some wind slabs with explosives up to size 2 and a couple of small natural wind slabs, one of which was triggered by a cornice fall. Some small loose dry avalanches in steep terrain were also reported. A few more small wind slabs in the alpine were reported on Sunday.
Snowpack Summary
Last week's storm snow has been redistributed into now aging wind slabs, which sit on top of the Jan 30 interface. Specific areas exposed to the wind may also have strastrugi. The mid-pack is generally weak facets, while depth hoar over a crust forms on an even weaker base. The snowpack is the weakest in eastern areas where snow depths are low. In these areas, the basal weaknesses should be carefully considered. See the snow profile from Bow summit on Feb 14th.
Weather Summary
Monday: A mix of sun and cloud with light NW winds at ridgetop. No new snow. Treeline temperatures will be between -12 and 15°C.
Terrain and Travel Advice
- Be careful as you transition into wind-affected terrain.
- Be mindful that deep instabilities are still present in the snowpack.
- Closely monitor how the new snow is bonding to the old surface.
Avalanche Problems
Wind Slabs
Lingering hard wind slabs exist on alpine lee features. Potential failure planes are either old weak facet layers or the Jan 30 layer of facets, sun crusts, and isolated surface hoar beneath the recent snow.
Aspects: All aspects.
Elevations: Alpine.
Likelihood: Unlikely - Possible
Expected Size: 1 - 2