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.
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.
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.
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.
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.
