Avalanche Forecast

Unsettled weather is forecast for the weekend. This will bring mostly cloudy skies, new snow 5-10 cm, and moderate to strong southwest winds at ridgetop. Freezing levels will rise to 1500 m during the day and drop overnight. 

On Thursday, numerous small size 1 wind slabs, dry loose, and wet loose avalanche activity were observed. 

On Wednesday, the region saw another natural cycle of wet loose, dry loose, wind slabs up to size 2, and wet slabs up to size 3. Additional reports continue to trickle in with deep persistent slabs up to size 4 from Tuesday- primarily occurred on southern aspects.

On Monday and Tuesday, a widespread natural avalanche cycle occurred with storm/wind slabs up to size 3 on all aspects, with the most reactivity noted on south-facing aspects. Numerous wet loose and wet slab avalanches occurred at treeline and below (size 1-3). A few of the larger size 3 notable wet slab and deep persistent slab avalanches that were reported are suspected to have failed on the early December rain crust near the base of the snowpack.

10-20 cm of new snow overlies up to 20 cm of denser snow above 2000 m and tapers rapidly at lower elevations. A melt-freeze crust exists on all aspects as high as 2000 m and to mountain top on solar aspects. Below the crust, the top 10-30 cm of the snowpack is moist. 50-60 cm of snow now sits over the mid-March interface at upper elevations. 

Westerly winds have formed reactive wind slabs on leeward terrain in the alpine and exposed treeline terrain.

The early-December rain crust is approximately a metre off the ground. Reports have recently indicated that large slab avalanches have failed on this interface earlier this week following a rain and warming event. This layer may be dormant now due to colder weather, however, may appear again during the next big warm-up or increased load from wind, snow and/or rain. 

• Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
• Wind slabs may be poorly bonded to the underlying crust.
• As surface loses cohesion due to melting, loose wet avalanches become common in steeper terrain.
• Pay attention to cornices and give them a wide berth when traveling on or below ridges.
• When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.