Avalanche Forecast
Issued: Dec 23rd, 2019 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Storm Slabs and Persistent Slabs.
kdevine,
Avalanche Canada
The recent snow added load to buried weak layers and may still be reactive to human triggers. Conservative terrain selection is recommended.
Summary
Confidence
Moderate - Uncertainty is due to how quickly the snowpack will recover and gain strength.
Weather Forecast
MONDAY NIGHT - Mainly cloudy / southeast wind, 10-30 km/h / alpine low temperature near -11
TUESDAY - Mainly cloudy / south wind, 10-30 km/h / alpine high temperature near -10
WEDNESDAY - A mix of sun and cloud / light northwest wind / alpine high temperature near -9
THURSDAY - A mix of sun and cloud / light southwest wind, 20-50 km/h / alpine high temperature near -8
Avalanche Summary
There is a notable weak layer of surface hoar that is down 40-100 cm and human triggering remains likely. Treat this layer with caution and choose conservative terrain.
On Sunday, there were reports of numerous natural and explosives triggered avalanches up to size 2.5
On Saturday, there were a few reports of natural and human triggered avalanches up to size 2. Check out this MIN report detailing the touchy conditions found in the Allan Creek area on Saturday.
On Friday, there were a few reports of natural and human triggered avalanches. Check out this great MIN report from Allan Creek that outlines reactive storm slab conditions. Here is another great MIN report about similar conditions further north in the region.
Snowpack Summary
The Cariboos have seen up to 70 cm of new snow over the past week, with most of it falling between Thursday afternoon and Saturday morning.
40-100 cm of snow is now sitting on a widespread layer of feathery surface hoar crystals. This layer has been responsible for several recent avalanches in the region. There is some uncertainty as to whether or not this layer will gain strength in the near future and so it should be treated with caution.
A weak layer formed in late November is now buried around 1 m or more below the surface. This is the layer of concern relating to the persistent slab avalanche problem. The weak layer may present as surface hoar, a crust, facets or a combination, depending on elevation and aspect.
Terrain and Travel
- Continue to make conservative terrain choices while the storm snow settles and stabilizes.
- Keep in mind that human triggering potential persists as natural avalanching tapers off.
- Be aware of the potential for large avalanches due to the presence of buried surface hoar.
- Storm slabs in motion may step down to deeply buried weak layers resulting in very large avalanches.
Problems
Storm Slabs
Storm slabs could still be triggered by humans, especially in wind loaded areas.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Persistent Slabs
There is a weak layer of surface hoar down 40-100 cm. Numerous recent avalanches have occurred on this layer and human triggering is a possibility.
Another weak layer that formed in late November is now down about 100-150 cm. This layer could be triggered from shallow snowpack areas, and it is also possible for avalanches triggered on the shallower layer to step down to this layer, resulting in very large avalanches.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Dec 24th, 2019 5:00PM
