Avalanche Forecast
Issued: Dec 19th, 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
Storm slabs are widespread and are expected to be reactive. Avoid avalanche terrain in the alpine, including exposure from above. Choose very conservative terrain as human triggered avalanches are likely.
Summary
Confidence
Moderate - Uncertainty is due to the track & intensity of the incoming weather system. Forecast snowfall amounts are uncertain.
Weather Forecast
THURSDAY NIGHT - Flurries, 10 cm / southwest wind, 50-70 km/h / alpine low temperature near -9
FRIDAY - Flurries, 5-10 cm / southwest wind, 40-60 km/h / alpine high temperature near -6 / freezing level 1200 m
SATURDAY - Flurries, 5-10 cm / southeast wind, 10-20 km/h / alpine high temperature near -6 / freezing level 800 m
SUNDAY - Cloudy with sunny periods / southeast wind, 20-30 km/h / alpine high temperature near -8
Avalanche Summary
Natural avalanche activity is expected to taper off somewhat, though natural avalanches are still possible. Human triggered avalanches remain likely.
Heavy snowfall likely resulted in a cycle of natural avalanches on Tuesday and Wednesday, leaving storm slabs very reactive to human triggering. Observations were limited on Tuesday and Wednesday due to poor visibility.
Snowpack Summary
A continuous wave of storms has delivered anywhere from 30-60 cm of snow to the Cariboos over the past few days. 50-90 cm of recent snow now sits above a widespread layer of large, feathery surface hoar crystals. New snow is expected to continue to accumulate and consolidate above this layer over the next few days, maintaining a high likelihood of human-triggered avalanches.
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. Below this, a variety of crusts from late October are buried deeper in the snowpack.
Problems
Storm Slabs
Continuous snowfall and strong wind has formed touchy storm slabs. The conditions are primed for avalanches.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Persistent Slabs
A couple of weak layers formed in late November and early December are now sitting about 1 m below the surface.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Dec 20th, 2019 5:00PM
