There is a big warm-up on the way for Wednesday with freezing levels expected to reach almost 2200 m and valley bottom temperatures up to 5 degrees. Avoid avalanche terrain during the warmth and stick to shaded slopes, sheltered by trees.
As you approach treeline, expect to encounter slab development. Today, the wind was redistributing snow well into tree line. Take the time to investigate what the recent snow is sitting on and how it is bonding.
This layer exist as surface hoar in sheltered areas and sun crust on steep southerly aspects 20 to 30cm down. We have only observed a few avalanche on this interface so far. As more slab develops over this layer, we expect it to become more reactive.
There's a big warm-up coming our way. Strong NW flow will continue to produce 60 km/hr winds in alpine areas with up to 5 additional cm falling by Wed evening. Wednesday will see the freezing levels rise to between 2000 and 2200 m with even some light rain forecast for valley bottoms. Thursday also warm and cooling down for Friday.
Strong winds have redistributed 20-30 cm of recent snow at upper elevations creating wind slab on lee slopes. At tree line and below the recent storm snow is beginning to develop into a slab, which overlays the Jan 30 surface hoar and sun crust. This interface is found 20 to 30cm down. Shallow snowpack areas remain weak and faceted.
Lake Louise patrollers knocked out a few hard slabs to size 1 with explosives today. Sunshine did avalanche control and saw results of cornice and windslabs up to size 1.5.
