Wind Slabs
N
NE
E
SE
S
SW
W
NW
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible
- Size
- 1.5–2.5
Wind slabs exist in exposed alpine terrain. Size and sensitivity to triggering could be greater where wind slabs have formed over a crust.
Avalanche forecast
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Apr 7 – 8, 2022Avalanche Canada
Archived · expired 4 years ago
Avalanche danger
Sat
Sun
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
2 · Moderate
Highlights
Continually assess the snow surface and watch for natural avalanche activity as you move through terrain. There is uncertainty in how the snowpack will respond to the rapidly changing freezing levels.
Avalanche problems
Cornices
NNEESESSWWNW- Alpine
- Treeline
- Below treeline
- Likelihood
- Likely
- Size
- 1.5–2.5
Natural cornice falls remain likely due to elevated freezing levels.
Loose Wet
NNEESESSWWNW- Alpine
- Treeline
- Below treeline
- Likelihood
- Very Likely
- Size
- 1.5–2.5
Wet loose avalanches will likely occur on steep terrain on all aspects and elevations, except high north terrain.
Confidence
Low - Uncertainty is due to difficult to forecast freezing levels.
Weather Forecast
Thursday night: No new snow expected. Moderate southwest winds shifting to strong south. Possibility of a temperature inversion with above freezing layer at treeline.
Friday: Mostly cloudy with rain at lower elevations and up to 5 cm of new snow at higher elevations. Strong south winds. Freezing level around 2000 m in the north and near 3000 m in the south of the range.
Saturday: Mostly cloudy with light flurries bringing trace amounts of new snow. Light southwest winds and freezing levels around 1530 m.
Sunday: A mix of sun and cloud with no new snow expected. Light west winds and freezing levels around 1300 m.
Avalanche Summary
On Wednesday one size three natural wind slab was observed on a northeast aspect at 2300 m.
Over the past few days ski cutting has produced wind slab avalanches up to size 1.5. These avalanches have generally been on north and east aspects in treeline terrain. Explosive control has produced storm and wind slab avalanches up to size 2.5 on all aspects at treeline and above in the western part of the region where more storm snow was recorded. Several small cornice falls have also been observed .
We suspect that large wet loose avalanches will be observed with elevated freezing levels.
Snowpack Summary
Wind slabs could still be found in alpine terrain on north and east aspects. Moist snow will likely be observed on all aspects and elevations. A new crust will form as the freezing level falls in the evening.
A thick rain crust with facets above from early December is buried around 150 cm deep. Large avalanches were naturally triggered on this layer during the last significant warming event in western terrain near the Bugaboos. Avalanche activity on this layer will become unlikely as the freezing level falls.
Terrain and Travel
- Back off slopes as the surface becomes moist or wet with rising temperatures.
- Avoid exposure to slopes that have cornices overhead.
- Be careful with wind loaded pockets, especially near ridge crests and roll-overs.