Avalanche Forecast

Bundle up in your warmest gear, arctic air is here! 

Monday Overnight: Clear skies. Alpine temperatures around -25 C. Light to moderate northeasterly winds. 

Tuesday: Cold and clear. An alpine high of -20 C. Light northeasterly winds.

Wednesday: Mainly cloudy with light snowfall. Winds shifting northwest and strengthening moderate to strong. Alpine temperatures rising to -15 C.

Thursday: Partially cloudy. Light to moderate northwest winds. Alpine temperatures around -15 C.

Sunday was an active day for avalanche activity! Numerous human-triggered storm slabs and wind slabs were reported mainly in the alpine and treeline, with many of these avalanches failing on the mid-February drought layer. Several natural wind slab, storm slab, and dry loose avalanches occurred, some as a result of cornice failures. 

In the north of the region, a natural avalanche cycle likely occurred during the peak of the storm on Saturday afternoon. Numerous human-triggered storm and wind slabs were reported throughout the day. In the south of the region, wind slabs were reactive to human triggering, with natural loose dry avalanches observed out of steep terrain in the alpine.

Explosive control last week initiated some larger persistent slabs up to size 3 on north-facing aspects at treeline.

Last weekend's storm brought 20-80 cm of new snow accompanied by southwesterly winds. The north of the region received highest snowfall amounts, with tapering amounts to the south. Below ~1200 m the majority of the precipitation fell as rain, with 10-20 cm of snow now overlying a thick melt-freeze crust. 

Up to 120 cm now overlies the mid-February drought layer. This layer is comprised of surface hoar in sheltered areas, a melt-freeze crust at lower elevations, a sun-crust on steep solar aspects, and hard wind-affected snow in the alpine and exposed treeline. In many areas, the storm snow is bonding poorly to this firm layer.  

The mid-January surface hoar/crust layer is now down 50-150 cm in the snowpack. This layer has not been reactive to skier traffic in the past week but continues to show reactivity in snowpack tests. With a significant amount of new snow, this layer could start to 'wake up' or be triggered from a large load like a cornice fall or a shallower slab avalanche stepping down to this layer. 

The facet/crust layer that formed in early December is now buried around 150 to 250 cm. Human triggering of this layer is unlikely, except perhaps on a re-loaded bed surface or in a shallow snowpack area. This layer may become a concern during periods of warming or heavy loading. 

• Don't be too cavalier with decision making, storm slabs may remain sensitive to human triggering.
• Recent wind has varied in direction so watch for wind slabs on all aspects.
• Use small low consequence slopes to test the bond of the new snow.
• Shooting cracks, whumphs and recent avalanches are strong indicators of an unstable snowpack.