Avalanche Forecast
Issued: Dec 23rd, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs and Wind Slabs.
jsmith,
Avalanche Canada
Numerous, large persistent slab avalanches have been reported in the northern portion of this region in recent days.
Conservative terrain choices will be the key to playing safe.
Summary
Confidence
Avalanche Summary
There have been numerous natural and skier triggered very large(up to size 3) persistent slab avalanches reported on all aspects at treeline and above in the Esplanade range over the past week. They have been failing on a weak layer of surface hoar down 50-70 cm.
This weak layer is a concern throughout much of the region.
Snowpack Summary
5-15 cm of new snow on Saturday and moderate southwest wind have formed fresh wind slabs on lee features at treeline and above.
The primary layer of concern in much of this region is a weak layer of surface hoar down 50-70 cm. This layer may be less likely to trigger in areas that have a strong, supportive crust above.
In the southern portion of the region, weak facets near the ground may be the primary layer of concern. Especially in shallow, rocky areas in the alpine.
Average snowpack depths at treeline are 70-120 cm which tapers rapidly below treeline.
Weather Summary
Saturday Night
Clear skies, west alpine wind 10 to 20 km/h, treeline temperature -8 °C.
Sunday
Sunny skies, southwest alpine wind 10 to 20 km/h, treeline temperature -10 °C.
Monday
Sunny skies, southwest alpine wind 10 to 20 km/h, treeline temperature -10 °C.
Tuesday
Mix of sun and cloud, west alpine wind 30 to 40 km/h, treeline temperature -8 °C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Avoid shallow snowpack areas, rock outcroppings and steep convex terrain where triggering is most likely.
- Look for signs of instability: whumphing, hollow sounds, shooting cracks, and recent avalanches.
- Surface hoar distribution is highly variable. Avoid generalizing your observations.
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
Problems
Persistent Slabs
The primary layer of concern in much of this region is a weak layer of surface hoar down 50-70 cm. This layer may be less likely to trigger in areas that have a strong, supportive crust above.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Wind Slabs
5-15 cm of new snow on Saturday and moderate southwest wind have formed fresh wind slabs on lee features at treeline and above.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 24th, 2023 4:00PM
