Avalanche Forecast
Regions: Banff, Banff Yoho Kootenay, East Side 93N, Field, Kootenay, LLSA, Lake Louise, Sunshine, West Side 93N.
Cool temperatures are forecast for Thursday, but pay attention to solar radiation and how quickly the day is warming up. Some loose wet avalanches may occur if day is warmer then forecasted.
Plan on starting and finishing your day early.
Confidence
Moderate
Avalanche Summary
No slab avalanches reported in the last few days.
Last week, on Saturday, skiers in the Ferris Glacier area remote-triggered a wind slab 60 cm deep on NE alpine terrain at ~2750 m. On Friday, skiers remotely triggered a wind slab at ~2850 m on St. Nicholas size 2.5 that stepped down to deeper layers in a rocky area, and occurred on steep, unsupported ENE facing terrain.
Snowpack Summary
Crusts on solar aspects to ridgetop, with crusts on all aspects at treeline and below. 20-40 cm of dry snow on north-facing alpine slopes with wind slabs in alpine lee areas.
In thinner snowpack areas a 30-70 cm stiff midpack sits over weak facets and depth hoar. On high north slopes, this weakness remains a concern. Elsewhere, crusts in the upper snowpack overlay this midpack slab. If these crusts are thick, and remain frozen, they provide some strength over the weakness.
Weather Summary
Thursday - mix of sun and cloud, cool temperatures (alpine highs -3°C), light northerly winds, and freezing levels 1900 - 2000 m.
Friday - will see mostly sunny skies, warmer temperatures (alpine highs -1°C), light westerly winds, and freezing levels to 2400 m.
Saturday - slightly cooler, cloudy skies and light flurries, up to 5-10 cm possible.
Avalanche Problems
Persistent Slabs
A midpack slab up to 80 cm thick sits on the weak, facetted lower snowpack. On all but high north aspects, recent sun crusts and the March 27 rain crust cap this slab, providing some security. Use caution in higher, thin snowpack areas or where these crusts are weak or breaking down with heating.
Aspects: North, North East, East, West, North West.
Elevations: Alpine.
Likelihood: Unlikely - Possible
Expected Size: 2 - 3