Rising freezing levels will further destabilize a complex snowpack with several avalanche problems. Conservative terrain selection is critical.
This problem encompasses several weak layers throughout the upper and mid snowpack. Remote triggers and wide propagation have been observed. Resulting avalanches have been large and destructive.
Loose wet avalanches will become increasingly likely as temperatures rise. Loose wet avalanches have potential to act as triggers to deeper weak layers.
Basal facets remain a concern in steep, rocky alpine features with thin-to-thick snowpack transitions. Avalanches triggered on this layer have been large and destructive.
On Friday in the Dogtooth range, a group of skiers accidentally triggered a size 4 (!!!) (absolutely enormous) avalanche from a ridgetop and were thankfully (physically) unharmed.
This adds to a lonnng list of large to very large avalanches on various weak layers throughout the east Cariboos, northern Selkirks, and west Purcells in recent days, including natural, rider and remote triggered size 2-3.5.
Light snowfall accumulates in the alpine while wet flurries moisten surfaces below as freezing levels creep up the mountain.
Beneath lies a complex snowpack containing several layers of concern that continue to produce avalanche activity:
Facets formed during the mid January cold snap sit 15-30 cm deep.
A surface hoar/facet/crust layer formed in early January sits 60-80 cm deep.
Another surface hoar layer that was buried in early December is now 130+ cm deep and remains a concern above 2000 m where it is not capped by a crust.
The lower snowpack is characterized by weak basal facets in many areas. Avalanches on this layer have been large and destructive.
Saturday night
Up to 10 cm of new snow. Southwest alpine wind 10-20 km/h. Treeline temperature -1 °C. Freezing level 1500 m.
Sunday
Mostly cloudy with wet flurries brining 5-10 mm of mixed precipitation. Southwest alpine wind 10-20 km/h. Treeline temperature 0 °C. Freezing level 2000 m.
Monday
A mix of sun and cloud. Southwest alpine wind 20-30 km/h. Treeline temperature +2 °C. Freezing level 2500 m.
Tuesday
Mostly cloudy with scattered flurries. Southwest alpine wind 10-20 km/h. Treeline temperature 0 °C. Freezing level dropping to 2000 m.
More details can be found in the Mountain Weather Forecast.
