Numerous wind slabs and the occasional deep slab has been the pattern over the last couple of days, and the next few days to come. Use good judgment and resist steep terrain as we come out of the cold weather.
Moderate to strong W-N winds have formed wind slabs in lees areas of the alpine and treeline. In the past couple days these wind slabs have been reactive to skier traffic, and have failed naturally with ongoing wind loading.
The lower snowpack is comprised of weak facets and depth hoar with the upper snowpack forming a 40 to 90cm thick slab above the weakness. Not much has changed with this layer and human triggering remains a concern anywhere this weak layer is present.
On Mt. Field, a size 2.5 natural deep slab was observed. It ran within 200m of the Kicking Horse River, occurring within the last 24 hours. A large cornice fell down which triggered a slab on Mt. Bosthworth, and the debris ran to mid-runout. Lake Louise patrol triggered two size 2 wind slabs that gauged down into facets with large explosives.
Moderate to strong W-N winds have formed wind slabs at treeline and in the alpine. Below this, the upper snowpack contains weak layers 20-40 cm deep (Jan. 4th) and 30-60 cm deep (Dec. 17th) that are generally unreactive. The Nov 16 deep persistent layer is down 40-90 cm and continues to produce variable sudden test results. In areas west of the divide, the snowpack is more supportive than in eastern areas.
Warming temperatures which will bring things back to seasonal over the next two days. A trace of snow is expected on Tuesday. Winds will remain in the strong range from the West, Tuesday through Thursday.
More details can be found in the Mountain Weather Forecast
