Avalanche Forecast

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Monday: Mainly cloudy with isolated flurries and a trace of new snow, continuing overnight. Light to moderate southwest winds. Alpine high temperatures around -8.Tuesday: Mainly cloudy with isolated flurries and a trace of new snow, continuing overnight. Moderate to strong southeast winds. Alpine high temperatures of -8.Wednesday: Cloudy with continuing isolated flurries and about 2 cm of new snow. Light to moderate southeast winds. Alpine high temperatures of -7.

Reports from Saturday included one remotely (from a distance) triggered Size 1.5 wind slab releasing from a steeper northwest-facing slope at around 1500 metres. The slab depth was 40-60 cm.Friday's reports showed a notable increase in persistent slab activity at lower elevations in the Howson Range. In this area, three Size 2 releases failed on steeper terrain with remote triggers on the mid-December weak layer, found 50 cm below the surface. Another report from last week mentioned numerous natural storm slab releases from Size 1-2 north of Kispiox. These were suspected to have released over a layer of surface hoar that may not be widely distributed.Looking forward, our storm slab problem is diverging into more distinct wind slab problems at higher elevations and more isolated storm slab over surface hoar issues at mid elevations. Lower elevations have become an increasing concern in areas where the upper 50 cm of the snowpack has settled into a slab over the persistent mid-December weak layer.

Recent light snowfalls have gradually brought about 20-30 cm of new snow to the region. The new snow has buried a temperature crust that likely exists well into the alpine. There are also reports of more isolated pockets of surface hoar beneath the new snow at lower alpine and treeline elevations. This surface hoar is noted in our avalanche activity discussion for having produced numerous storm slab releases in a localized area after the storm ended. Below the new snow interface, deeper weak layers in the snowpack include a few crusts and surface hoar layers that formed in early January and December. Most recent reports suggest the snow is well bonded to these layers, but recent persistent slab activity over a surface hoar and facet 'combo' at low elevations suggests that a dangerous persistent slab problem may be developing as the mid and upper snowpack consolidate into a stiffer slab over this layer.