Recent storm snow remains reactive, especially on sun affected slopes.
Persistent avalanche activity has raised danger ratings for the Southern Selkirks, carefully consider open and convex slopes at treeline. In other areas, treeline danger is moderate.
Persistent weak layers of surface hoar and/or crust can be found 50 to 100 cm deep.
The problem is most likely found in the southern part of the Selkirks (e.g. Valhalla, Goat and Kokanee ranges), especially on open convex slopes at treeline elevations.
This problem exists on all aspects, however danger will increase on sun-affected slopes throughout the day.
30-50 cm of recent storm snow may continue to be reactive to human triggers in specific terrain features. This includes steep sun-exposed slopes, wind loaded slopes, and open convexities at treeline where there could be buried sun crusts or surface hoar layers.
At lower elevations, expect wet avalanches to be likely as freezing levels rise and strong sun is expected. Minimize exposure to slopes with moist or wet surface snow.
SATURDAY NIGHT: Partly cloudy, light northwest winds. Isolated flurries possible. Freezing levels drop to valley bottom.
SUNDAY: Strong sun, light westerly winds becoming moderate in the late afternoon. Freezing levels rise to 1500 m. Alpine high of -2.
MONDAY: Cloudy with isolated flurries bringing up to 2-8 cm of snow, moderate to strong northwest winds. Freezing levels rise to 1500 m, alpine high of-2.
TUESDAY: A mix of sun and cloud with isolated flurries. Light northeast winds. Freezing levels at valley bottom. Alpine high of -6.
While storm slab activity continues to gradually taper off, recent activity indicates the impact of the sun on surface weak layers. On Friday, numerous storm slabs were naturally triggered by solar input on south and east facing slopes to size 2.5. On north facing slopes (not affected by solar), storm slabs were still reactive to human triggers to size 2. In general, storm slab avalanches have been more frequent and larger in the Selkirks than in the Monashees.
Over the past two weeks we have seen large (size 2 to 3) persistent slab avalanches on buried surface hoar and crust layers. Most of the activity has been in the Valhalla, Goat, and Kokanee Ranges at treeline elevations. Activity reported on Friday included:
Recent storm snow has settled into 30 to 50 cm of heavy powder at upper elevations.On sun affected slopes and lower elevations (below 1800 m), surface snow has become moist and crusty.
The new snow sits over a reactive crust-facet-surface hoar combination. This interface continues to produce human and triggered avalanches on all aspects, and naturally triggered avalanches on sun affected slopes.
Buried weak layers sit 50-100 cm deep, buried between mid February and mid January. They both consist of surface hoar and/or melt-freeze crusts. Recent trends indicate these layers have been more reactive in southern Selkirks around the Valhalla, Kokanee, and Goat Ranges. Several natural and human triggered avalanches have been produced on these layers in the last 3 days. See the Avalanche Summary for full details
