Avalanche Forecast
Issued: Feb 27th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs.
ahanna,
Avalanche Canada
Watch for fresh, reactive wind slabs which may exist in atypical terrain features. Westerly wind may have southerly or northerly components, depending on elevation.
Summary
Confidence
Moderate - Uncertainty is due to how quickly the snowpack will recover and gain strength.
Weather Forecast
Saturday night: Flurries bringing a trace of snow, strong wind above 2000 m, extreme northwest at ridgetop.
Sunday: Flurries bringing a trace of snow. Moderate increasing to strong southwesterly winds above 2000 m. Freezing level around 1300 m.
Monday: 5-10 cm new snow. Strong southwesterly winds. Freezing level 1500 m.
Tuesday: Around 5 cm new snow. Moderate southwesterly winds. Freezing level 1000 m.
Avalanche Summary
Pinwheeling and small loose wet sluffing was observed on steep sun exposed slopes on Saturday afternoon.
Otherwise, recent avalanche activity around and north of Duffey Lake has been limited to loose dry sluffing and small human triggered soft slabs in the recent storm snow. This MIN is a great reminder that terrain traps can increase the consequences of even small avalanches. Glad everyone is unharmed.
Reports from the Coquihalla indicate quite limited natural storm slab activity during the storm with only a couple of size 2's noted near Hope.
Snowpack Summary
Recent storm snow has been variable across the region, the Coquihalla receiving around 60-80 cm and other areas in the 15-30 cm range. This snow appears to be bonding well to underlying surfaces including a sun crust on steep solar aspects and a rain crust below 1500 m in the Coquihalla area.
At upper elevations, recent snow is wind affected and is likely undergoing continued transport as winds pick up into Sunday morning. Wind direction has been predominantly westerly but may also may have southerly or northerly components, depending on elevation.
A weak layer composed of a crust, facets or surface hoar depending on elevation/aspect is now down 70-120 cm. This layer, buried in late January, continues to be noted in snowpack tests with mixed results. There have been no recent avalanches reported on this layer. Large triggers, such as an avalanche in motion, cornice fall, or intense loading from snow/ wind and/or a rapid rise in temperature can awaken these deeper weak layers.
The lower snowpack is well settled and strong in most areas.
Terrain and Travel
- Wind slabs are most reactive during their formation.
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- Recent wind has varied in direction so watch for wind slabs on all aspects.
Problems
Wind Slabs
Reactive wind slabs may be found in atypical terrain features. Wind direction has been predominantly westerly but may also may have southerly or northerly components, depending on elevation.
Aspects: North, North East, East, South East, South.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Feb 28th, 2021 4:00PM
