Snow, strong winds and rising temperatures on Sunday are perfect conditions for the development of wind slab. Heads up out there.
Weather Forecast
A pulse of snow starting on Sunday (15cm in the Icefields area and 6cm in the Jasper area) will be accompanied by strong Westerly winds and rising temperatures.
Snowpack Summary
The snowpack is highly variable throughout the forecast region. Alpine elevations are very wind effected with some drifting at higher elevations from moderate to strong south westerly winds.
Avalanche Summary
One large avalanche observed running on steep rock slabs on Whistler Mountain which was likely triggered by redistributed blowing snow.
Confidence
Timing, track, or intensity of incoming weather system is uncertain
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.