Avalanche Forecast
Regions: Boundary, East Stikine, Kispiox, Ningunsaw, Northwest Coastal, Northwest Inland, Stewart, West Stikine.
Stick to low-angle terrain away from overhead hazard. Wind, warm temperatures, and a complex snowpack are causing multiple avalanche problems.
Confidence
Moderate
Avalanche Summary
On Monday and Tuesday, several natural persistent slab avalanches were reported up to size 3, several of which failed on the weak layer from early March. Some of these were triggered by cornice failures, and two were remotely triggered from up to 100 m away. Some natural wind slab avalanches were also observed.
On Sunday, a size 2 avalanche was rider-triggered on a northwest aspect in the alpine. This avalanche was believed to have occurred on the February drought layer.
Snowpack Summary
50 to 100 cm of recent snow has been redistributed by variable winds. This snow fell on previously wind-affected surfaces and crusts on steep south-facing terrain.
Three layers of concern currently exist in the upper-mid snowpack. Surface hoar that formed in mid-March can be found 65-85 cm below the snow surface. Below this, another layer of surface hoar that formed in early March can be found at a depth of 90 to 125 cm. Additionally, a layer of facets, surface hoar, and/or a crust from mid-February is buried 115 to 195 cm deep.
The remainder of the snowpack is well consolidated, and there are no current concerns.
Weather Summary
Wednesday Night
Mostly clear. 20 to 40 km/h northeast ridgetop wind. Treeline temperature -5 °C. Freezing level dropping below 1400 m.
Thursday
Mostly sunny. 30 to 60 km/h northeast ridgetop wind. Treeline temperature -1 °C. Freezing level 1200 m.
Friday
Partly cloudy. 30 to 60 km/h east ridgetop wind. Treeline temperature -3 °C. Freezing level 1000 m.
Saturday
Mostly sunny. 20 to 40 km/h east ridgetop wind. Treeline temperature -3 °C. Freezing level 1000 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Recent wind has varied in direction, so watch for wind slabs on all aspects.
- Avoid steep, sun-exposed slopes when the air temperature is warm or when solar radiation is strong.
- Be aware of the potential for large, destructive avalanches due to deeply buried weak layers.
- Cornice failures could trigger large and destructive avalanches.
- Make conservative terrain choices and avoid overhead hazard.
Avalanche Problems
Persistent Slabs
Several weak layers persist in the snowpack. These layers continue to produce large avalanches and are a primary avalanche problem.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Likely
Expected Size: 2 - 3.5
Wind Slabs
Recently formed wind slabs are expected to remain reactive, and human-triggering remains possible.
Cornices are weak, and especially with mild temperatures and sun, natural cornice failures are possible.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1 - 2