Avalanche Forecast
Regions: Boundary, East Stikine, Kispiox, Ningunsaw, Northwest Coastal, Northwest Inland, Stewart, West Stikine.
Weak layers in the snowpack continue to be a concern. A cautious approach is recommended, especially in high-elevation, north terrain where the snowpack remains most complex.
Confidence
Moderate
Avalanche Summary
On Saturday morning, explosives triggered several size 1 slabs, which were around 25 cm thick.
On Friday, several wind slabs and wet loose avalanches were observed.
On Thursday, natural wet loose avalanches up to size 2 were observed on all aspects at treeline and in the alpine.
Earlier in the week, some natural wind slab avalanches stepped down to persistent weak layers in the middle of the snowpack.
Snowpack Summary
A widespread surface crust formed following Thursday's warming event. The new snowfall from Friday and Saturday has been redistributed by moderate winds in wind-exposed terrain.
Three layers of note currently exist in the mid-snowpack and still have the potential to cause large avalanches:
A layer of surface hoar and a crust that formed in mid-March is 50 to 80 cm below the snow surface.
Another layer of surface hoar that formed in early March buried 70 to 120 cm.
A layer of facets, surface hoar, and/or a crust from mid-February is buried 120 to 200 cm deep.
The remainder of the snowpack is well consolidated.
Weather Summary
Saturday Night
Partly cloudy. 10 to 20 km/h northwest ridgetop wind. Treeline temperature -9 °C. Freezing level valley bottom.
Sunday
A mix of sun and cloud. 10 to 20 km/h northwest ridgetop wind. Treeline temperature -2 °C. Freezing level 1000 m.
Monday
Increasing cloud cover. 20 to 30 km/h west ridgetop wind. Treeline temperature -2 °C. Freezing level 1000 m.
Tuesday
Cloudy with snowfall 5-10 cm. 30 to 40 km/h southwest ridgetop wind. Treeline temperature -1 °C. Freezing level 1200 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Be aware of the potential for large, destructive avalanches due to deeply buried weak layers.
- Watch for newly formed and reactive wind slabs as you transition into wind-affected terrain.
- Pay attention to cornices and give them a wide berth when traveling on or below ridges.
- Limit exposure to steep, sun exposed slopes, especially when the solar radiation is strong.
Avalanche Problems
Persistent Slabs
Weak layers from February and March remain reactive in the snowpack, but likely need a heavy trigger to cause a failure. These layers are most likely to be triggered on high north-facing terrain.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 2 - 3
Wind Slabs
Recently formed wind slabs may be reactive to human triggers.
Aspects: North, North East, East, South East.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1 - 1.5