Avalanche Forecast
Issued: Jan 6th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Persistent Slabs.
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Avalanche Canada
Heightened avalanche conditions exist on wind loaded slopes and steep rocky terrain.
Summary
Confidence
Moderate - Uncertainty is due to the complexity of the snowpack’s structure.
Weather Forecast
Clearing weather after a front crosses the region on Wednesday night.
WEDNESDAY NIGHT: 5-10 cm of snow, moderate southwest wind, treeline temperature around -4 C.
THURSDAY: Cloudy in the morning then clearing in the afternoon, light northwest wind, treeline temperatures around -6 C.
FRIDAY: Mix of sun and cloud, light southwest wind, temperatures around -6 C.
SATURDAY: Mix of sun and cloud, light west wind, temperatures around -8 C.
Avalanche Summary
Explosive avalanche control produced a few size 2-3 wind slab avalanches on Tuesday. Last weekend there were numerous natural size 2-3 slab avalanches. Most of these were storm slab avalanches in alpine terrain, although some of the reports from the upper Elk Valley included avalanches at treeline elevations that likely failed on 60-100 cm deep surface hoar layers.
Snowpack Summary
Moderate snowfalls and strong southwest wind over the past few days has left hard surfaces and wind slabs in exposed terrain. The upper snowpack consists of several layers of old wind slabs, while the lower snowpack consists of decomposing crusts and weak faceted snow. In the Elk Valley a decomposing surface hoar layer can be found around one of these crusts 50-100 cm below the surface. Avalanche activity on these layers in the lower snowpack have been sporadic, mostly occurring during natural avalanche cycles. However, this snowpack structure is always a concern for human triggering on steep rocky slopes with variable snowpack depths.
Terrain and Travel
- Be careful with wind slabs, especially in steep, unsupported and/or convex terrain features.
- Avoid shallow, rocky areas where the snowpack transitions from thick to thin.
- Be aware of the potential for large avalanches due to the presence of buried weak layers.
Problems
Wind Slabs
Strong southwest wind and a series of moderate snowfalls over the past few days has likely left wind slabs in steep leeward terrain.
Aspects: North, North East, East, South East, South, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
Triggering large avalanches on weaknesses in the lower snowpack remains a possibility. In some areas the concern is weak snow around crusts 50 to 100 cm deep, while in others it's weak snow near the bottom of the snowpack. This problem is best managed by avoiding steep rocky slopes and approaching avalanche terrain with caution.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Jan 7th, 2021 4:00PM
