Avalanche Forecast
Regions: Boundary, East Stikine, Kispiox, Ningunsaw, Northwest Coastal, Northwest Inland, Stewart, West Stikine.
Daytime warming may destabilize the snow at lower elevation, on steep slopes that face the sun.
Reduce your exposure to large slopes above you, and cornices.
Confidence
Moderate
Avalanche Summary
In the past 3 days, a few large natural and explosive controlled avalanches up to size 3 have happened during the heat of the day.
On Friday, a failing cornice triggered a size 3 avalanche on an eastern slope in the alpine. This avalanche is believed to have occurred on the March 5th surface hoar layer.
Where a thick, supportive surface crust is found, we expect that triggering avalanches on buried weak layers is unlikely.
Snowpack Summary
5 to 25 cm of new snow sits on variably wind affected snow in open terrain at upper elevations. A crust is found up to 1800 m and higher on solar slopes.
Three layers of note currently exist in the upper-mid snowpack.
A layer of surface hoar and a crust that formed in mid-March can be found 50 to 80 cm below the snow surface.
Another layer of surface hoar that formed in early March can be found at a depth of 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, and there are no current concerns.
Weather Summary
Wednesday Night
Mostly cloudy with flurries. 20 to 30 km/h southeast ridgetop wind. Treeline temperature -6°C.
Thursday
Mostly cloudy with 5 to 10 cm of snow. 20 to 50 km/h southeast ridgetop wind. Treeline temperature 0 °C. Freezing level 1200 m.
Friday
Mostly cloudy with up to 5 cm of snow. 20 to 40 km/h southwest ridgetop wind. Treeline temperature -3 °C. Freezing level 900 m.
Saturday
Mix of sun and cloud with flurries. 10 to 30 km/h southwest ridgetop wind. Treeline temperature -3°C. Freezing level 1000 m
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Avalanche activity is unlikely when a thick melt-freeze crust is present on the snow surface.
- Be aware of the potential for large, destructive avalanches due to deeply buried weak layers.
- Cornice failures could trigger large and destructive avalanches.
- Avoid steep, sun-exposed slopes when the air temperature is warm or when solar radiation is strong.
Avalanche Problems
Persistent Slabs
Several weak layers persist in the snowpack. These layers are most likely to be reactive at upper elevations where no surface crust has formed. Surface instabilities or large triggers may step-down to these deeper layers.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 2 - 3.5
Cornices
As temperatures rise, large cornice falls are becoming a concern. They can potentially trigger persistent slab avalanches on the slopes below. Carefully manage your exposure to overhead hazards, during the warmest part of the day.
Aspects: All aspects.
Elevations: Alpine.
Likelihood: Possible - Likely
Expected Size: 1 - 2.5
Loose Wet
Lower elevation, steep slopes, that are being warmed by the sun, will be able to produce natural avalanche during the heat of the day.
Aspects: East, South East, South, South West.
Elevations: Treeline, Below Treeline.
Likelihood: Unlikely - Possible
Expected Size: 1 - 2