Rider triggered avalanches are possible on specific terrain features. There are a few factors to consider when evaluating snow and terrain for avalanche potential; including wind and sun exposure as well as elevation and snowpack depth.
Recent snow and wind have reverse-loaded fresh wind slabs into atypical terrain features. Watch for wind drifted snow below ridge crests and rollovers and in cross-loaded terrain.
Weak, sugary crystals at the bottom of the snowpack produced large avalanches in late February. This problem may reactivate with any rapid change or shock to the snowpack, such as dramatic warming.
Recent avalanche observations have been limited to solar-triggered loose dry out of steep south aspects up to size 1.5 on Wednesday.
Last week the region saw numerous natural wind slab and cornice-triggered avalanches up to size 2.
On Tuesday our field team observed a size 3 deep persistent slab avalanche near Hankin that they estimated to be around a week old. The slab propagated across the full steep, rocky feature. This has been the latest of a pattern of intermittent large deep persistent slab activity in the alpine. Observations from late February include a cornice-triggered size 2.5 at Hudson Bay and several explosive controlled size 2-3 near Ningunsaw.
10-20 cm of recent wind affected snow sits over previously wind-hardened surfaces in the alpine. Sun crust or moist snow can be found on steep solar aspects.
Several crusts, layers of facets, or surface hoar can be found in the top 150 cm of the snowpack, but have not shown any significant avalanche activity or snowpack test results recently.
The lower snowpack consists of weak, basal facets which may become active with any rapid change or shock to the snowpack, such as heavy loading or dramatic warming.
Thursday night
Clear. Light easterly wind. Alpine low -14 ˚C.
Friday
A mix of sun and cloud. Moderate southeasterly wind. Alpine high -12 ˚C.
Saturday
Mostly cloudy with isolated flurries and sunny breaks. Moderate easterly wind. Alpine high -16 ˚C.
Sunday
Mostly cloudy with isolated flurries and sunny breaks. Light easterly wind. Alpine high -14 ˚C.
More details can be found in the Mountain Weather Forecast.
