Avalanche Forecast
Issued: Mar 9th, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs.
mconlan,
Avalanche Canada
A persistent slab problem requires diligence and a conservative mindset. Be confident the problem doesn't exist before committing to consequential terrain.
Summary
Confidence
Weather Forecast
WEDNESDAY NIGHT: Clear skies with no precipitation, 20 km/h west wind, alpine temperature -8 C.
THURSDAY: Mix of sun and cloud with no precipitation, 20 to 30 km/h west wind, alpine temperature -7 C.
FRIDAY: Cloudy with snowfall, accumulation 5 cm, 40 to 60 km/h southwest wind, alpine temperature -6 C.
SATURDAY: Cloudy with snowfall, accumulation 15 to 25 cm, 40 km/h southwest wind, alpine temperature -6 C.
Avalanche Summary
Two more persistent slab avalanches were triggered by riders on Tuesday. They occurred at treeline and alpine elevations on a northeast aspect, similar to the trend of previous avalanches.
It remains possible that humans could trigger this layer, where it exists.
Snowpack Summary
A dusting of snow sits on a surface melt-freeze crust on all aspects below around 1500 m and on sun-exposed slopes into the alpine. Settled dry snow remains on shaded slopes above around 1500 m. Reports suggest that recent strong northerly wind did not form new wind slabs, though extra caution is advised in steep terrain where isolated pockets may have formed.
Around 40 to 80 cm deep, a weak layer of sugary faceted grains may be found above a melt-freeze crust that formed in February. This layer has produced numerous human-triggered and natural avalanches over the past week. Activity has been most prevalent on north to northeast aspects between 1600 m and 2100 m. Check out this forecaster blog for more info.
There are no deeper concerns at this time.
Terrain and Travel
- Be aware of the potential for large avalanches due to the presence of a persistent slab.
- Look for signs of instability: whumphing, hollow sounds, shooting cracks, and recent avalanches.
- Use extra caution around cornices: they are large, fragile, and can trigger slabs on slopes below.
Problems
Persistent Slabs
A weak layer of faceted grains above a hard melt-freeze crust may be found around 40 to 80 cm deep. This layer continues to produce large avalanches that have the potential to propagate far. The problem is most prevalent on north to northeast aspects between 1600 m and 2100 m.
Aspects: North, North East, East, West, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Mar 10th, 2022 4:00PM
