Avalanche Forecast
Issued: Mar 5th, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs, Loose Wet and Cornices.
rbuhler,
Avalanche Canada
Wind slab formation is expected in exposed terrain at higher elevations due to ongoing periods of moderate northerly wind. Use extra caution around cornices and steep south-facing slopes during the heat of the afternoon.
Summary
Confidence
Low - Uncertainty is due to the limited number of field observations. Uncertainty is due to the speed, direction, or duration of the wind and its effect on the snowpack. Uncertainty is due to the timing or intensity of solar radiation and its effect on the snowpack.
Weather Forecast
A ridge of high pressure brings one more day of dry and sunny conditions for Sunday before conditions change on Monday.Â
Saturday Night: Clear, light to moderate N wind, freezing levels around 1500 m.
Sunday: Sunny, light to moderate N wind, freezing levels climbing to around 2000 m.
Monday: Mainly cloudy with a chance of flurries, strong NW wind, freezing levels around 2000 m in the morning, dropping to around 1000 m in the afternoon.
Monday night and Tuesday: Snowfall up to 15 cm, light to moderate NW wind, freezing levels around 800 m.
Avalanche Summary
On Friday, this MIN report includes numerous size 1 loose wet avalanches on east through south aspects.Â
A persistent slab avalanche problem is prevalent just north of the region in the southern Sea to Sky. While there hasn't been any observations of this problem in the South Coast region, it may exist in some of the data sparse parts of the region outside of the North Shore. This blog post goes into further details on the problem.Â
Snowpack Summary
A melt-freeze crust is now expected to be capping the snowpack on all aspects at elevations below around 1700 m and on sun-exposed slopes at higher elevations. Dry surface snow may still exist on high elevation northerly aspects. Periods of moderate northerly wind over the weekend may have redistributed this old storm snow in exposed high elevation terrain and formed wind slabs.Â
A weak interface from mid-February can be found 30-60 cm deep which may include a sun crust, facets, and/or spotty surface hoar. This interface was bonding poorly at the beginning of the storm but has become less of a problem now where the snowpack is capped by a robust crust. At higher elevations where the snowpack is not capped by a crust, the interface may still be reactive. Check out the Sea to Sky Forecast and this forecaster blog to learn more about the recent reactivity on this layer which is still reactive just north of the region.
50-80 cm below the surface, a 30 cm thick crust caps the underlying snowpack which is well-settled and strong.
Check out the latest North Shore Snowpack video for additional details for that area.Â
Terrain and Travel
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Minimize exposure to sun-exposed slopes when the solar radiation is strong.
- Cornices become weak with daytime heating or solar exposure.
Problems
Wind Slabs
Wind slab formation may be ongoing over the weekend as we continue to expect periods of moderate wind from the north. Dry snow was reported above around 1700 m so wind transport should be expected above that elevation in wind-exposed terrain.
Aspects: East, South East, South, South West, West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Loose Wet
With each subsequent day of melt-freeze conditions, loose wet avalanches will become less likely. However, extra caution is still recommended on steep sun-exposed slopes during the heat of the afternoon. Where the crust is breaking down or non-existent, loose wet avalanches will be more likely.
Aspects: East, South East, South, South West, West.
Elevations: All elevations.
Likelihood
Expected Size
Cornices
Looming cornices have grown large during the recent storm. They could still pose a threat from above or below, and are expected to become weak when the sun is at its strongest.
Aspects: North, North East, East.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Mar 6th, 2022 4:00PM
