Avalanche Forecast
Issued: Dec 18th, 2020 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.
kdevine,
Avalanche Canada
New snow and wind will mean that storm slabs are to be expected, and will likely be reactive to human triggering, especially in wind loaded areas.
Summary
Confidence
Weather Forecast
FRIDAY NIGHT - Flurries, 5-15 cm / west wind, 50-80 km/h / alpine low temperature near -8
SATURDAY - Flurries, 5-15 cm / southwest wind, 40-80 km/h / alpine high temperature near -4
SUNDAY - Sunny with cloudy periods and isolated flurries / southwest wind, 30-60 km/h / alpine high temperature near -6
MONDAY - Mainly sunny / light winds / alpine high temperature near -7
Avalanche Summary
There were a few natural avalanches up to size 2 reported on Thursday. Check out this great MIN report from Hankin that outlines a few avalanche observations.
A wind slab avalanche likely stepped down to the facets described in the snowpack summary, producing a large avalanche near Smithers earlier this week.
Please consider sharing your observations to the Mountain Information Network Thank you to those that have already submitted this winter!
Snowpack Summary
20-40 cm of recent fresh snow and strong southwest wind has likely formed reactive storm slabs. This new snow likely sits on a melt-freeze crust from early December, which may have weak and sugary faceted grains growing around it.
A crust that was buried in early November is near the base of the snowpack. This crust has weak facets associated with it. These facets have produced large avalanches in both the south and north of the region within the past week.
Snowpack depths vary substantially with aspect, elevation, and wind exposure.
Terrain and Travel
- Watch for fresh storm slabs building throughout the day.
- Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
- If triggered, wind slabs avalanches may step down to deeper layers resulting in larger avalanches.
- Avoid shallow, rocky areas where the snowpack transitions from thick to thin.
Problems
Storm Slabs
20-40 cm of recent fresh snow with strong southwest winds has likely formed reactive storm slabs. These will probably be very easy to trigger on wind loaded slopes.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Deep Persistent Slabs
Weak faceted grains near the base of the snowpack have the potential of forming large and destructive avalanches. The most likely place to trigger this layer would be on shallow and rocky slopes. Smaller avalanches may also have the potential of stepping down to this layer.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 19th, 2020 4:00PM
