Avalanche Forecast
Issued: Mar 10th, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs and Wind Slabs.
mconlan,
Avalanche Canada
New snow will soften conditions but may also form slabs over the day. Don't forget about the lurking weak layer that could still be triggered.
Summary
Confidence
Weather Forecast
THURSDAY NIGHT: Cloudy with isolated flurries, trace accumulation, 20 to 30 km/h southwest wind, alpine temperature -8 C.
FRIDAY: Cloudy with snowfall, accumulation 5 to 10 cm, 40 to 60 km/h southwest wind, alpine temperature -7 C.
SATURDAY: Cloudy with snowfall, accumulation 10 to 20 cm, 40 km/h south wind, alpine temperature -6 C.
SUNDAY: Cloudy with snowfall, accumulation 10 cm, 20 km/h southwest wind, alpine temperature -5 C.
Avalanche Summary
No new avalanches were reported on Wednesday. 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.
Looking forward, new wind slabs will start out small but will continue to grow over the day. Steep, lee terrain features should be entered cautiously.
Snowpack Summary
New snow and strong southwest wind will begin to form new wind slabs in lee terrain features. The snow will build on a thin layer of variably wind affected, faceted snow or surface hoar that overlies a hard melt-freeze crust found on all aspects below around 1500 m and on sun-exposed slopes into the alpine. The snow will fall onto previously wind-affected and faceted snow on shaded slopes above 1500 m.
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 about one or two human-triggered avalanches per day 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
- Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
- 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
Wind Slabs
New snow and southwest wind may form wind slabs in lee terrain features. The slabs will grow over the day and may not bond well to underlying layers.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Mar 11th, 2022 4:00PM
