Avalanche Forecast

Moderate - Timing or intensity of solar radiation is uncertain on Wednesday

On Tuesday night and Wednesday morning, expect a mix of sun and cloud with isolated spring "power flurries". Clouds should scatter by mid-day on Wednesday while Thursday and Friday will be mainly clear. Ridgetop winds will be light to moderate from the northwest on Wednesday, becoming generally calm on Thursday and Friday. Daytime freezing levels should sit at about 1200m for the forecast period.

On Sunday, natural and human triggered wind slab activity to size 1.5 was observed on a variety of aspects at treeline and in the alpine. The avalanches formed in response to new snow and wind on Saturday. In one case, a smaller surface avalanche stepped down and triggered a size 3 slab on a southwest facing slope at treeline. It is unknown what interface the larger slab failed on. As stormy weather tapers-off and a dry ridge gradually builds over the province, solar radiation may become the driver for natural avalanche activity.

At treeline and in the alpine you're likely to find wind slabs which formed during Saturday's stormy weather. 50-100cm below the surface you'll find a persistent weak layer comprised of surface hoar, facets and/or a thick crust. This layer seems variably reactive. In other words, it's still really touchy in some places while in other spots it's really tough to trigger, and there's not much of a reliable pattern telling us what exact aspects are most suspect. I'd continue to be suspicious of steep, unsupported features at treeline and in the alpine as this layer has the potential for very large avalanches. Below this interface, the snowpack is generally gaining strength. At ridgetop, cornices are huge and potentially unstable.