Avalanche Forecast
Issued: Feb 5th, 2022 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs, Storm Slabs and Loose Wet.
ldreier,
Avalanche Canada
Rising temperatures will keep the likelihood for humans to trigger avalanches increased, particularly where recent snow loaded a buried weak layer.
Summary
Confidence
Moderate - Uncertainty is due to the limited number of field observations.
Weather Forecast
SATURDAY NIGHT: Cloudy, trace of new snow, moderate southwest wind, alpine temperature -3 C, freezing level 1200 m.Â
SUNDAY: Cloudy with flurries in the morning and sunny in the afternoon, trace of snow, light southwest wind, alpine temperature 0 C, freezing level rising to 1900 m.
MONDAY: Cloudy with snowfall, 10 to 15 cm new snow, moderate west wind, alpine temperature -4 C, freezing level 1500 m.
TUESDAY: Cloudy with snowfall, up to 5 cm new snow, light to moderate southwest wind, alpine temperature -5 C, freezing level 1500 m.Â
Avalanche Summary
Observations on Friday were limited due to bad visibility. A natural avalanche cycle of small storm slab avalanches up to size 1.5 was reported. Large avalanches are expected in areas where the buried surface hoar described in the Snowpack Summary exists.Â
Looking towards Sunday, avoidance of consequential avalanche terrain is your best bet for having a safe day. Storm and wind slabs will be very touchy due to all the recent snow and wind. The snow will need time to stabilize.
Snowpack Summary
The recent storm brought around 30 to 50 cm of snow. The snow has likely formed storm slabs in sheltered areas and wind slabs in lee terrain features from strong southwest wind. These slabs will remain touchy for the remainder of the weekend as the freezing level rises and the air gets warmer.
The snow will be particularly touchy where it is loading a weak layer of surface hoar crystals. This layer is likely anywhere from 50 to 100 cm deep. Reports suggest that the surface hoar is most prominent in sheltered openings at and below treeline but could extend into wind-sheltered terrain in the alpine. Example terrain features to treat as suspect include the lee side of protected ridges, openings in the trees, cut blocks, and burns. On south aspects, a melt-freeze crust may exist instead of surface hoar.
The lower snowpack is generally strong and well-bonded.
Terrain and Travel
- Potential for wide propagation exists, fresh slabs may rest on surface hoar, facets and/or crust.
- Watch for signs of instability like whumpfing, hollow sounds, shooting cracks or recent avalanches.
- Avoid steep slopes when air temperatures are warm, or solar radiation is strong.
Problems
Persistent Slabs
The recent snow loaded a widespread weak layer of surface hoar crystals. The layer may be found around 50 to 100 cm deep and is most prominent in areas sheltered from the wind at and below treeline. Example terrain features to particularly treat as suspect include the lee side of ridges, openings in trees, cut blocks, and burns.
The buried weak layer was reported to be very active in the Blue River area and is present up to treeline in the Wells Gray area and around Valemount.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Storm Slabs
The recent storm brought 30 to 50 cm new snow which has formed slabs. Warm temperatures will further promote slab development. Expect to find storm slabs in sheltered areas and wind slabs in wind-exposed terrain from strong southwest wind.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Loose Wet
Warm temperatures and sun in the afternoon will increase the likelihood of wet loose avalanches. Be especially cautious on and below slopes that are exposed to the sun.
Aspects: South East, South, South West, West.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Feb 6th, 2022 4:00PM
