Avalanche Forecast
Issued: Apr 12th, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs.
rbuhler,
Avalanche Canada
Small wind slabs are expected to remain reactive on Wednesday. Wind direction has been variable and wind slabs should be expected on all aspects in exposed high elevation terrain.
Summary
Confidence
Weather Forecast
Tuesday night: Partly cloudy, light to moderate northeast wind, treeline low around -15 °C.
Wednesday: Mainly cloudy with sunny breaks, light to moderate northeast wind, treeline high around -8 °C.
Thursday: A mix of sun and cloud, light east wind, treeline high around -6 °C.
Friday: A mix of sun and cloud, light variable wind, treeline high around -4 °C.
Avalanche Summary
On Sunday, a natural size 1.5 wind slab was observed on an east aspect at 2400 m which was 30 cm thick. Two natural cornice releases were also observed on northeast aspects which triggered slabs on the slopes below. Explosives triggered three cornices on north and east aspects between 2100 and 2600 m. Two of these triggered small wind slabs on the slopes below.
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 recent snowfall has buried a widespread melt-freeze crust which formed during the major warming event at the end of last week. 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.
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
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Recent wind has varied in direction so watch for wind slabs on all aspects.
- Wind slabs may be poorly bonded to the underlying crust.
- When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.
- Cornices often break further back than expected; give them a wide berth when traveling on ridgetops.
Problems
Wind Slabs
Wind slabs are expected to remain reactive to human-triggering in exposed high elevation terrain. Recent wind appears to have been mainly from the southwest in the north of the region and from the northeast in the south of the region. As a result of these variable winds, wind slabs should be expected on all aspects in wind-exposed terrain.
Aspects: All aspects.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Apr 13th, 2022 4:00PM
