Avoid avalanche terrain and exposure to overhead avalanche terrain.
Heavy rain and high freezing levels will continue to create very dangerous conditions.
Cornices are large and looming. Strong winds and warming temperatures may increase the sensitivity. Cornices may trigger wet slabs or may step down to the persistent slab, creating larger than expected avalanches.
Two layers of concern exist within the upper snowpack: a crust layer is 60 to 80 cm deep and a weak layer of surface hoar/facet is 100 to 200 cm deep. Warm temperatures and precipitation will continue to make this problem more sensitive.
Rising freezing levels and rain are continuing to soak the surface snow. Large avalanches are very likely in steep terrain. Wet slabs are more likely at upper elevations, while wet loose will be more likely at lower elevations.
On Thursday, numerous and very large avalanches (up to size 2.5-3) were reported near Fernie, indicating a widespread natural cycle. These included cornice falls, wet slabs and loose wet avalanches from all aspects and elevations. Persistent slabs (2 m deep crown) and a glide slab were also observed.
Looking ahead, natural avalanches are expected at all elevations during the ongoing warm storm, particularly in areas where avalanche paths have not yet released.
High freezing levels and heavy rain are continuing to soak the snowpack up to the mountain tops. Cornices are large and looming and are weakening with the ongoing warming.
Below this, a thick crust is found on all aspects and is buried down 50 cm. The thickness of the crust (from 1 to 10 cm) depends on elevation.
Multiple buried weak layers of surface hoar and/or crusts still exist in the top 120 cm of the snowpack and will likely become active with the additional load from heavy rain.
The mid and lower snowpack is well settled and strong in most areas.
The lower snowpack is soaked at lower elevations.
Thursday Night
Cloudy. 10 to 15 mm of rain at treeline. 70 km/h southwest ridgetop wind. Treeline temperature 2 °C. Freezing level 2700 m.
Friday
Cloudy. 20 to 30 mm of rain at treeline. 70 km/h southwest ridgetop wind. Treeline temperature 2 °C. Freezing level 2700 m.
Saturday
Cloudy. 1 to 3 mm of rain or snow at treeline. 40 km/h west ridgetop wind. Treeline temperature 0 °C. Freezing level 2000 m.
Sunday
Mostly cloudy. 1 to 3 cm of snow at treeline. 40 km/h west ridgetop wind. Treeline temperature -4 °C. Freezing level 1800 m.
More details can be found in the Mountain Weather Forecast.
