Avalanche Forecast
Regions: East Kakwa, Kakwa, McBride, McGregor, North Rockies, Pine Pass, Renshaw, Robson, Sugarbowl, Tumbler.
Fresh wind slabs will develop on Sunday.
For the best riding conditions and lowest hazard, look for soft, wind-sheltered snow at lower elevations.
Confidence
Moderate
Avalanche Summary
On Friday, a large (size 2) naturally-triggered large persistent slab avalanche failed on a north-facing alpine slope near Crescent Spur. Several naturally-triggered wind slabs have been reported across the region over the past few days, with some being triggered by collapsing cornices. They were generally in the size 1-2 range (small to large). Whumpfing and shooting cracks were also reported by skiers near McBride - see this great MIN for details.
Snowpack Summary
Up to 20 cm of new snow has accumulated in the last few days, with up to 10 cm more forecast to fall throughout Sunday. Southwesterly winds are expected to be building fresh wind slabs near and just below ridge crests at alpine and treeline elevations.
40 to 80 cm of snow rests on a weak layer buried in early March that is a hard melt-freeze crust, or surface hoar in wind-sheltered treeline areas. This layer is of greatest concern in sheltered north and east-facing upper-elevation terrain.
A buried weak layer of surface hoar and/or faceted grains from mid-February lies 50 to 100 cm deep. This layer appears to be strengthening and has not triggered any recent avalanches.
The lower snowpack remains well-settled.
Weather Summary
Saturday Night
Mostly cloudy. 30 to 40 km/h southwest ridgetop wind. Treeline temperature -5 °C.
Sunday
Cloudy with 0 to 10 cm of snow, up to 15 cm coming Sunday night. 30 to 45 km/h southwest ridgetop wind. Treeline temperature -1 °C. Freezing level rising to 1400 m.
Monday
A mix of sun and cloud. 40 to 50 km/h west ridgetop winds. Treeline temperature 0 °C. Freezing level rising to 1700 m.
Tuesday
A mix of sun and cloud. 30 to 40 km/h southwest ridgetop wind. Treeline temperature +3 °C. Freezing level rising to 1900 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Seek out wind sheltered terrain below treeline where you can avoid wind slabs and find great riding.
- Watch for newly formed and reactive wind slabs as you transition into wind-affected terrain.
- Use ridges or ribs to avoid areas of wind-loaded snow.
- Surface hoar distribution is highly variable. Avoid generalizing your observations.
Avalanche Problems
Wind Slabs
Be cautious if you move into wind-affected terrain. Newly formed wind slabs are expected to be reactive to human triggers.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood: Likely
Expected Size: 1 - 2
Persistent Slabs
A persistent weak layer of surface hoar or facets remain a concern in the upper 40 to 80 cm of the snowpack.
Aspects: North, North East, East, North West.
Elevations: Alpine, Treeline.
Likelihood: Unlikely - Possible
Expected Size: 2 - 3