Avalanche Forecast

Moderate - Timing, track, or intensity of incoming weather system is uncertain

TUESDAY: Mostly cloudy with light snowfall beginning late afternoon, light to moderate northwesterly winds, alpine temperature near -14 C, freezing level below valley bottom.WEDNESDAY: Cloudy with snowfall, accumulation 20 to 40 cm with the most in the east of the region, moderate westerly winds, alpine temperature near -6 C, freezing level near 1400 m.THURSDAY: Cloudy with snowfall early morning, accumulation 20 cm, moderate westerly winds, alpine temperature near -15 C, freezing level below valley bottom.

On Sunday, numerous wind, storm, and persistent slab avalanches were reported, from small to large (size 1 to 3).  They were triggered by skiers, explosives, and naturally between 1800 m and 2100 m on all aspects and with slabs 30 to 200 cm deep.  The persistent slab was suspected to have released on a deeply buried sugary facet layer and propagated about 400 m.  Similar avalanches were reported on Saturday, showing a steady trend of avalanche activity.Last Tuesday, a size 2.5 avalanche on a northeast facing slope at 1920 m resulted in a single fatality in Clemina Creek. More details available here.Looking forward, dangerous snowpack conditions will persist in the region until a more stable weather pattern governs and we see a decrease in avalanche observations. All three of our buried weak layers (described below) continue to produce large, destructive avalanches from natural and human triggers. Recent storm slabs and wind slabs have the potential to step down to deeper weak layers, which could produce large, destructive avalanches.

Around 40-100 cm of storm snow from the past two weeks has formed a slab that sits over an unstable snowpack.  There are three active weak layers that we are monitoring:1) The first layer is found beneath the recent storm snow and is formed of a crust and/or surface hoar layer that was buried in mid-January. The surface hoar is up to 10 mm in size, found at all elevation bands and has been very reactive on north through east aspects between 1900-2600 m.2) Deeper in the snowpack, the early-January persistent weak layer is found 60 to 120 cm below the surface. This layer was reported as the most active persistent weak layer during a recent natural avalanche cycle that took place in the region. It was also very reactive to recent explosives control.3) Another weak layer buried mid-December consisting of a facet/surface hoar/crust combination, which is 100 to 180 cm deep. It has been most problematic at and below tree line. Many avalanches that failed at shallower weak layers 'stepped down' to this interface during the recent avalanche cycle and explosives control.