Avalanche Forecast
Issued: Apr 13th, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Cornices and Wind Slabs.
rbuhler,
Avalanche Canada
Small reactive wind slabs may still be lingering in exposed high elevation terrain.
Cornices have grown large and may fail under the weight of a human. Give them a wide berth when travelling on ridges and watch for signs that they may be weakening with extended sun exposure.
Summary
Confidence
Moderate - Uncertainty is due to the limited number of field observations. Uncertainty is due to the speed, direction, or duration of the wind and its effect on the snowpack.
Weather Forecast
Wednesday night: Partly cloudy, light east wind, treeline low around -15 °C.
Thursday: A mix of sun and cloud, light east wind, treeline high around -5 °C.
Friday: A mix of sun and cloud, light variable wind, treeline high around -4 °C.
Saturday: A mix of sun and cloud, light to moderate east wind, treeline high around -3 °C.
Avalanche Summary
On Monday, explosives triggered several cornice releases up to size 2.5 above 2400 m in the western part of the region. A couple of these triggered small slabs on the slopes below. Most notably, one of them triggered a triggered an 80 cm thick slab which was expected to have released on facets which were buried at the end of March.Â
Observations are limited this time of year. If you are getting out in the backcountry, please consider contributing to the Mountain Information Network.
Snowpack Summary
10-30 cm of aging storm snow has buried a widespread melt-freeze crust which formed during the major warming event on April 8. Recent moderate to strong winds have redistributed the recent snow forming reactive wind slabs in exposed terrain at higher elevations. The recent wind direction appears to have been variable across the region with mainly southwest wind in the north of the region and mainly northeast wind in the south of the region.Â
A thick rain crust with facets above from early December is buried around 100-200 cm deep. Large avalanches were naturally triggered on this layer during the last significant warming event in the western part of the region near the Bugaboos. With the current cold temperatures, avalanche activity on this layer is unlikely. However, we expect it will wake up again with the next major input of warming and sun, or rainfall.
Terrain and Travel
- Cornices often break further back than expected; give them a wide berth when traveling on ridgetops.
- Watch for wind-loaded pockets especially around ridgecrest and in extreme terrain.
- Recent wind has varied in direction so watch for wind slabs on all aspects.
- When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.
Problems
Cornices
Cornices are reported to be large but are generally not expected to fail naturally with the current cold conditions. Give cornices a wide berth when travelling on ridges and watch for signs that they may be weakening if they are exposed to extended periods of sun.
Aspects: All aspects.
Elevations: Alpine.
Likelihood
Expected Size
Wind Slabs
Small wind slabs may be still be reactive in steep or convex leeward features in exposed alpine terrain features. Wind direction has been variable across the region so wind slabs should be anticipated on all aspects in wind-exposed terrain.
Aspects: All aspects.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Apr 14th, 2022 4:00PM
