Avalanche danger is expected to become HIGH before the end of the day as heavy precipitation, strong winds, and rising temperatures make their way into the region. Be aware of conditions changing over the day, especially in overhead terrain.
Rapid loading of new snow during Friday's storm will build new storm slabs at higher elevations. Forecast strong winds and warm temperatures will speed slab formation as new snow accumulates.
Wet loose avalanches will be in increasing problem on Friday at lower elevations that see rain instead of snow accumulating. This problem will affect increasingly high elevations over the day.
Thursday night: Cloudy with flurries bringing 10-15 cm of new snow. Moderate to strong southwest winds.
Friday: Cloudy with increasing snowfall bringing 25-30 cm of new snow, transitioning to rain below about 1700 metres, continuing overnight. Strong southwest winds. Alpine high temperatures approaching 0 as freezing levels climb to 1800-2000 metres.
Saturday: Cloudy with continuing flurries bringing 15-25 cm of new snow and new snow totals to 40-60 cm, closer to 5-10 cm below 1500 metres. Moderate to strong southwest winds shifting northwest and easing. Alpine temperatures dropping to about -7 as freezing levels fall from 1900 to 1000 metres over the day.
Sunday: Cloudy with isolated flurries and a trace of new snow. Light southwest winds. Alpine high temperatures around -10.
Due to continuous stormy weather, there have been daily avalanches reported in the region. Most of these have been storm and wind slab avalanches, on all aspects, at all elevations. They have been triggered by humans, explosives, and naturally.
There was a notable avalanche reported in the northern Monashees on Saturday. It was a natural size 4 persistent slab avalanche. It was triggered by a wind slab avalanche that stepped down to a deeper layer.
There was also a notable size 3 persistent slab avalanche in the northern Selkirks on Saturday that was triggered by explosives on a southwest aspect in the alpine.
Looking forward, heavy precipitation, strong winds, and rising temperatures will promote increasing natural avalanche activity on Friday. During this time, occasional persistent slab releases such as those mentioned above may result from avalanche activity in surface snow layers.
35-45 cm of new snow is expected to fall at higher elevations in the region by end of day on Friday. The new snow will cover wind affected recent snow at alpine and upper treeline elevations while rain saturates the surface below about 1700 metres.
The mid and lower snowpack is generally well settled and strong, however, there is a weak layer of surface hoar currently buried 90 to 170 cm deep. This layer is suspected to have produced a few sporadic large avalanches recently reported in the north of the region.
