Avalanche Forecast
Issued: Jan 3rd, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Persistent Slabs.
shorton,
Avalanche Canada
Carefully evaluate your terrain choices, triggering storm slab avalanches remains a concern (especially at higher elevations).
Summary
Confidence
Moderate - Uncertainty is due to how quickly the snowpack will recover and gain strength. Uncertainty is due to the fact that persistent slabs are particularly difficult to forecast.
Weather Forecast
SUNDAY NIGHT: Cloudy with some isolated flurries and up to 5 cm of snow, moderate west wind, temperatures drop to -8 C.
MONDAY: Cloudy with isolated flurries and up to 5 cm of new snow, moderate southwest wind, temperatures around -4 C.
TUESDAY: 10-20 cm of snow overnight then light flurries during the day, moderate west wind, temperatures around -6 C.
WEDNESDAY: Cloudy with some isolated flurries, moderate southwest wind, temperatures around -2 C.
Avalanche Summary
The storm over the weekend resulted in a widespread cycle of storm slab avalanches in the Fernie area. This included numerous size 2-3 explosive and naturally triggered avalanches. Some of these occurred on bed surfaces of previous avalanches that had been reloaded by strong winds redistributing new snow.
Storm slabs are likely stabilizing in the coming days, but are still a concern and should be considered when assessing steeper and wind loaded slopes.
Snowpack Summary
Saturday night's storm brought 20-30 cm of heavy snow that should stabilize relatively quickly, but could still be a problem in steep and wind affected terrain.
In the Lizard Range, a melt-freeze crust has been reported around 20 to 50 cm deep and up to an elevation of 1900 m. A few reports suggest that sugary faceted grains may exist around the crust but others indicate no weakness. It remains to be seen if this layer will become an avalanche problem.
Around 50 to 100 cm deep, weak layers of feathery surface hoar and/or faceted grains may overly a hard melt-freeze crust. This layer appears to be bonding in certain areas of the region but remains suspect where it is well preserved.
Terrain and Travel
- Approach lee and cross-loaded slopes with caution.
- Don't be too cavalier with decision making, storm slabs may remain sensitive to human triggering.
- Be aware of the potential for large avalanches due to the presence of buried persistent weak layers.
- Storm slabs in motion may step down to deeper layers resulting in large avalanches.
Problems
Storm Slabs
Recent deposits of snow are still a concern for human triggering, especially at upper elevations and on freshly wind loaded slopes.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Persistent Slabs
Weak layers of feathery surface hoar and/or sugary faceted grains may be found above a hard melt-freeze crust around 50 to 100 cm deep. Although avalanche activity hasn't been reported on these weak layers for over a week, the likelihood of triggering will be heightened during this stormy period.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Jan 4th, 2021 4:00PM
