Avalanche Forecast
Issued: Jan 26th, 2023 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Deep Persistent Slabs.
rgoddard,
Avalanche Canada
Significant snowfall accumulation is forecasted for our area in the next 36 hours.
Expect storm slabs to form and new snow to be transported by associated wind.
Keep terrain choices conservative during this time.
Summary
Confidence
Moderate
Avalanche Summary
Avalanche control with the use of explosives produced three size 1.5 avalanches from wind slabs in the Fernie area on Wednesday. Ski cutting on Monday and Tuesday yielded more size 1 avalanches also produced from wind slabs.
Sunday saw a cornice fail naturally but it did not trigger buried weak layers in this instance. Even so, it's a great reminder to be mindful and to practice avoidance of overhead hazards.
Although they have not produced avalanches in the last few days, a deep persistent slab problem still affects the region and should steer you away from thin or variable depth snowpack locations and shallow rocky start zones throughout the region.
Snowpack Summary
New snow will be falling on wind slabs about 1800 m. Below treeline a surface hoar layer will be getting buried in sheltered areas and on south-facing aspects, a melt-freeze crust can be found getting covered over.
A crust/facet layer, 2 to 15 cm thick at treeline is 50 to 90 cm below the surface. Where it's thickest, it caps the settled and consolidated mid-snowpack.
Another crust/facet layer is down 70 to 150 cm. Below this crust, the basal snowpack is weak and faceted. The total snowpack depth ranges between 90 and 250 cm.
Weather Summary
Thursday Night
Cloudy, 6 to 12 cm accumulation, winds southwest 20 to 30 km/h, treeline temperatures around -6 C with freezing levels getting up to 1300 m.
Friday
Cloudy, 5 to 10 cm accumulation in the morning with up to another 10 cm in the evening, winds north 20 km/h, treeline temperatures around -5 C.
Saturday
A mix of sun and cloud, trace accumulation ending in the morning, winds northeast 30 km/h, treeline temperatures dropping down to -20 C.
Sunday
Mostly sunny, possible trace accumulation, winds northeast 20 to 30 km/h, treeline temperatures getting down to -25 C.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.
- Watch for changing conditions today, storm slabs may become increasingly reactive.
- In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.
- Recent wind has varied in direction so watch for wind slabs on all aspects.
- Avoid exposure to slopes that have cornices overhead.
Problems
Storm Slabs
By Saturday morning our region could see as much as 30 cm of new snow. This will be sitting on a range of surfaces that could include wind slabs, surface hoar, and / or a melt freeze crust. See snowpack summary for more details.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Deep Persistent Slabs
Faceted grains make up the basal snowpack and are gaining strength very slowly. This layer has been relatively quiet recently but can still be triggered with a heavier load, like a cornice fall for example, and in areas with a thinner snowpack. Any avalanche triggered this deep will likely be large and destructive.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Jan 27th, 2023 4:00PM
