Avalanche Forecast
Regions: Banff, Banff Yoho Kootenay, East Side 93N, Field, Kootenay, LLSA, Lake Louise, Sunshine, West Side 93N.
The mid-pack facet layer is still very evident and producing shears with snowpack tests. Although the natural activity on this layer has abated, skier triggered avalanches are still possible. Conservate terrain choices are still required.
Confidence
Moderate
Avalanche Summary
No new avalanches observed or reported. It was an overcast day so the loose wet activity that was reported on Sunday was not as big of a factor as it was on Sunday.
Snowpack Summary
15-30 cm of settled storm snow (since Friday) overlays the March 27 rain/temp crust which extends up to 2400m. Surface sun crust exist on solar aspects up to ridgetops and temperature crusts exist at lower elevations on polar aspects. The midpack consists of a 50-100cm dense one finger slab which sits over a persistent weak layer of facets from Jan/Feb. In most areas this facet layer extends to the ground.
Weather Summary
Unsettled conditions forecast for Tuesday and Wednesday bringing isolated flurries with accumulations up to 10 cm along the divide. A ridge of high pressure builds on Thursday brings clearing and a drying trend.
Winds will be light and freezing levels forecast to be around 1900m on Tuesday.
Terrain and Travel Advice
- Be mindful that deep instabilities are still present and have produced recent large avalanches.
- Give the new snow several days to settle and stabilize before pushing into bigger terrain.
Avalanche Problems
Persistent Slabs
A 60-100cm slab of dense snow now sits atop the persistent mid-pack facet layer from Jan/Feb. In thin snowpack areas weak depth hoar extends to the ground. There has been a lot of large avalanche activity on this facet layer, and where it hasn't avalanched, triggering this layer remains a big concern
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Possible - Likely
Expected Size: 1.5 - 3.5
Storm Slabs
Up to 30cm of settled of storm snow buries previous crusts and winds slabs. The new snow could fail as a storm slab in steep terrain, and has potential to step down to deeper weak layers in the snowpack. Any significant solar inputs will increase the likelihood of these slabs being triggered.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible - Likely
Expected Size: 1 - 2
Loose Wet
This problem is driven by air temperature and solar input. The latest storm snow sits on a crust and could slide easily if conditions warm, especially under strong sun. Heat and solar input remain uncertain in the models, so monitor conditions closely at the local level on Tuesday.
Aspects: South East, South, South West, West.
Elevations: Treeline, Below Treeline.
Likelihood: Possible
Expected Size: 1 - 2