Dry snow may remain in high elevation northerly terrain however, this is where triggering weak layers is most likely. Manage this high-consequence snowpack with low-consequence terrain.
Weak layers from January and February persist within the upper 100 cm of snow. Natural avalanche activity has tapered off with cooler temperatures; however, human triggering the persistent layers remains a concern.
Over the weekend, numerous natural and human-triggered avalanches, up to size 3.5, were reported at all elevations and aspects, many failing on the late January persistent weak layer.
On Sunday, a skier remotely triggered a size 2 persistent slab avalanche on a NW slope at 2300 m near Kaslo. The avalanche failed on the February weak layer and stepped down to the January weak layer.
A few centimeters of snow overlies a melt-freeze crust on all aspects, except northerly slopes above 2000 m, where surfaces remained dry through the warm-up. Below 1000 m, the snow surface may still be moist.
A weak layer, composed of facets, surface hoar, or a crust, is found 20 to 60 cm deep. Another persistent weak layer, buried in late January, lies 50 to 110 cm deep across the region. This layer also consists of surface hoar/facets or a crust, depending on the aspect.
The remaining snowpack is well-settled and strong.
Monday Night
Mainly clear skies. 5 to 10 km/h south ridgetop wind. Treeline temperature -6 °C. Freezing level drops to 1000 m.
Tuesday
Increasing cloud. 10 to 25 km/h southwest ridgetop wind. Treeline temperature -2 °C. Freezing level rising to 1700 m.
Wednesday
Cloudy with light flurries, 5 to 10 cm of snow. 10 to 30 km/h west ridgetop wind. Treeline temperature -4°C. Freezing level rising to 1300 m.
Thursday
A mix of sun and cloud. 15 to 30 km/h northwest ridgetop wind. Treeline temperature -3 °C. Freezing level rising to 1500 m.
More details can be found in the Mountain Weather Forecast.
