Avalanche Forecast
Regions: Banff, Banff Yoho Kootenay, East Side 93N, Field, Kootenay, LLSA, Lake Louise, Sunshine, West Side 93N.
Snowpack slowly adjusting, but human triggering remains a risk.
Confidence
Moderate
Avalanche Summary
Three skiers triggered a size 1.5 avalanche in Lipalian 3, just outside the Lake Louise ski area boundary. One skier was carried 60m but remained on the surface, uninjured. They responsibly reported the incident to patrol, preventing an unnecessary response. Meanwhile, Sunshine patrol triggered another size 2 deep slab with explosives in a similar location as yesterday's slide.
Snowpack Summary
10-30 cm of storm snow has fallen with mild temps and strong S-SW winds helping to form wind and storm slabs. This snow sits over a layer of weak facets, surface hoar or sun crust from the cold snap.
The mid-pack is generally weak facets, while depth hoar and crusts form 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.
Weather Summary
Valley temperatures will hover just above freezing, with ridge temperatures warming to -4°C by Wednesday evening. Expect minimal snowfall with persistent cloud cover. Winds will be strong and sustained from the west.
Terrain and Travel Advice
- In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and slopes above cliffs.
Avalanche Problems
Persistent Slabs
10-30 cm of storm snow and strong S-SW winds have loaded lee areas at treeline and above with new slabs up to 60 cm deep. This is sitting on a weak layer of facets, surface hoar or sun crust. Human triggering will remain likely in steep or wind loaded terrain for the next few days.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible - Likely
Expected Size: 1 - 2
Deep Persistent Slabs
The recent storm has added load to an already shallow and weak snowpack. With this additional weight, there may be a reawakening of this problem in isolated areas. Areas of concern include thin, shallow, and rocky slopes.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Unlikely
Expected Size: 1.5 - 2.5