Avalanche Forecast

Cooler, a mix of sun and clouds for the remainder of the week as a high pressure builds. A bit warmer temps to the south.

Wednesday Night: Mostly clear skies, light Southwesterly wind, freezing level valley bottom (600m). Alpine Low -7C.

Thursday: Cloudy with sunny periods, light Southeast wind, freezing level 1000 m. Alpine High -5C.

Friday: A mix of sun and clouds, light and variable winds, freezing level 700 m. Alpine Low -12C / High -10C

Saturday: A mix of sun and clouds, light and variable winds, freezing level 700 m. Alpine Low -13C / High -10C.

Avalanche hazard is highly variable and dependent on snowfall amounts and freezing lines experienced locally during this recent storm. Cooler temperatures and the passing of the storm should result in tapering avalanche hazard. 

On Wednesday numerous reports have come in about poor bonds of new snow to the freezing rain crusts from the recent storm. Additionally, avalanche control work was able to trigger large avalanches on the deep persistent layer in northerly shallow rocky terrain near treeline. This elevation would have been below the recent inversion, which further weakening the crust. 

On Tuesday, the buried surface hoar was reactive to skier traffic in steep terrain or where slab properties were present. Check out this MIN for avalanche activity from intentional ski cuts along Reudi's Ridge nearby to Kicking Horse. 

In adjacent regions where 30-50cm of snow was reported, a notable avalanche cycle was observed Monday into Tuesday. At the peak of this cycle reports of large avalanches (Size 2) naturally and from skier controlled and explosive control work on Tuesday. A few Very Large (Size 3) Natural avalanches were reported running to valley bottom along the highway corridor.  

Our eyes and ears in the mountains are limited this winter due to fewer professional observations. If you go out in the mountains, please share your observations on the Mountain Information Network (MIN). Photos are especially helpful! Thank you so much for all the great MINs submitted so far!

As things cool after high freezing levels, anticipate refrozen surfaces below treeline up to 1800m. Freezing rain was also observed at some locations to ridge top, but appears to have missed the northern Purcells. New snow is not bonding well to this melt freeze crust where present.  

Around 10-30 cm new snow fell Monday thru Wednesday as the recent storm shifted south. This recent 10-30cm of new snow sits on top of a buried melt-freeze crust on south aspects and widespread surface hoar tree line and below. While high freezing levels may have helped to break down the surface hoar, it will still be intact when snow remained cool. In other words, if there are no THICK rain crusts at and below tree line, be on the look out for buried surface hoar.  

The lower snowpack is characterized by a couple of crusts, the most notable is from rains in early November (Nov 5 Crust). This crust is sitting near the base of the snowpack, likely surrounded by a weak layer of sugary facets. It is most likely to be reactive to human triggers in shallow, rocky areas.

• Choose conservative terrain and watch for clues of instability.
• Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
• Potential for wide propagation exists, fresh slabs may rest on surface hoar, facets and/or crust.
• In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.