Great skiing continues during a break in snowfall. Watch for reactive wind slabs in exposed alpine and treeline terrain, and be mindful of deep persistent weak layer when transitioning into areas with a thinner snowpack.
Moderate to strong winds from multiple directions have moved recent snow, creating slabs in alpine and open treeline terrain. There is also more wind in the forecast, which is keeping the likelihood raised. Watch for these as you transition into wind-affected terrain.
The natural avalanche cycle on this layer has ended, but concern about human-triggered avalanches persists. Be wary of shallow areas, as this has been where the bulk of recent large avalanches have started, going from thin to thick (see avalanche summary).
No new natural avalanche observations were reported on Monday. Local ski hills triggered several size 2 wind slabs in the alpine using explosives. On Sunday, a skier-remote size 2 deep persistent slab was reported in the Lake Louise backcountry (see photo below). Although avalanche activity on the deep persistent layer has slowed, we continue to receive evidence of its reactivity.
Variable winds have created fresh windslabs in alpine and open treeline terrain. In sheltered areas, recent storm snow (20-30cm) remains preserved.
There is 40-80 cm over the Dec 15 melt-freeze crust (which is present to ~1800 - 2000m), 80-160 cm over the November facet/crust interface, and, in thinner snowpack areas, facets at the base.
Treeline snow depths range from 100-200cm plus.
A weak ridge of high pressure will linger over the forecast region on Tuesday. Expect a mix of sun and clouds, moderate to strong ridgetop winds, and no new precipitation. Over the next few days, temperatures will remain seasonably warm, with freezing levels near the valley bottom.
