Avalanche Forecast
Regions: Boundary, East Stikine, Kispiox, Ningunsaw, Northwest Coastal, Northwest Inland, Stewart, West Stikine.
The snowpack remains primed for human triggering.
Stick to conservative terrain and avoid overhead hazard, remote triggering is possible.
Confidence
Moderate
Avalanche Summary
Over the weekend widespread slab avalanches up to size 3.5 was reported. Activity has decreased but the potential for large and destructive avalanches remains.
Explosive control work on Monday produced slabs up to size 3.5 on the February weak layer. Remotely triggered slabs (from humans and vehicles) were also reported to size 3.
Looking forward, natural activity is expected to taper off but human triggering remains a significant concern.
Snowpack Summary
Recent storm snow has been wind affected in exposed terrain. Cornices are large and have recently triggered slab avalanches on the slopes below. South-facing slopes and low elevations hold a surface crust.
Facets, surface hoar (in sheltered terrain), and a crust on solar aspects that all formed during the February drought, are buried 50 to 100 cm deep. This layer has produced large natural and human-triggered avalanches this week.
Deeper in the snowpack, facets and a crust from early December can be found from 100 to 300 cm deep. This layer appears to be dormant but remains an isolated concern in this region.
Weather Summary
Tuesday Night
Partly cloudy. 20 to 30 km/h southeast ridgetop wind. Freezing level drops to valley bottom.
Wednesday
A mix of sun and cloud. 10 to 20 km/h southeast ridgetop wind. Treeline temperatures -4 °C. Freezing level 900 m.
Thursday
A mix of sun and cloud with up to 5 cm of snow possible. 30 to 40 km/h southwest ridgetop wind. Treeline temperatures -4 °C. Freezing level 900 m.
Friday
Cloudy with 10-20 cm of snow. 50 to 70 km/h southwest ridgetop wind. Treeline temperatures -3 °C. Freezing level 1100 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Be mindful that deep instabilities are still present in the snowpack.
- Conservative terrain selection is critical; choose gentle, low consequence lines.
- Avoid steep, sun-exposed slopes when the air temperature is warm or when solar radiation is strong.
- Cornice failures could trigger large and destructive avalanches.
Avalanche Problems
Persistent Slabs
Weak layers remain reactive, with potential for large avalanches. Warm temperatures and sun may increase reactivity on south-facing slopes.
Avalanches have potential to step down to the December weak layer in isolated areas.
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Possible - Likely
Expected Size: 2 - 3.5
Wind Slabs
Deposits of wind transported snow are expected to remain reactive, especially near ridge crests and rollovers. Recent winds have switched from east to southwest, so watch for slabs on all aspects and expect locally variable conditions.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible - Likely
Expected Size: 1 - 2.5