Avalanche Forecast
Issued: Dec 26th, 2019 3:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs and Wind Slabs.
ghelgeson,
Avalanche Canada
Watch for fresh wind slabs in upper elevation terrain. Natural persistent slab activity has slowed way down, but large avalanches may still be sensitive to human triggering. If you are increasing your exposure to avalanche terrain, do it gradually as you gather information.
Summary
Confidence
Moderate - Uncertainty is due to the fact that deep persistent slabs are particularly difficult to forecast.
Weather Forecast
It’s mostly dribs and drabs of snow for the next few days with increased wind in the higher alpine terrain features. A bigger storm is on the horizon as we finish the New Year.
THURSDAY NIGHT: Freezing level at valley bottom, moderate to strong south/southwest wind, potential for 4 to 10 cm by Friday morning.
FRIDAY: Broken cloud cover, freezing level at valley bottom, moderate to strong west/northwest wind, trace of snow possible during the day.
SATURDAY: Broken cloud cover, freezing level at valley bottom, moderate to strong south/southwest wind, trace of snow possible.
SUNDAY: Scattered cloud cover, freezing level at valley bottom, light variable wind, no significant precipitation expected.
Avalanche Summary
No new activity was reported on Monday, Tuesday or Wednesday.
On Sunday, there were reports of numerous natural and explosive triggered avalanches up to size 2.5
Snowpack Summary
The Cariboos have seen up to 70 cm of new snow over the past week.
40-100 cm of snow is now sitting on a widespread layer of feathery surface hoar crystals. There is some uncertainty as to how much strength this interface has gained over the last few days and 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 interface may present as surface hoar, a crust, facets or a combination, depending on elevation and aspect.
Terrain and Travel
- Start on smaller terrain features and gather information before committing to bigger terrain.
- Caution around convexities or sharp changes in terrain.
- Fresh wind slabs will likely form throughout the day, diligently watch for changing conditions.
- Avalanche hazard may have improved, but be mindful that deep instabilities are still present.
Problems
Persistent Slabs
All of the old storm snow is slowly settling into a slab which rests on weak surface hoar 40 to 100 cm below the surface. Natural avalanche activity has waned, but human triggering may still be possible, especially in more challenging/complex terrain. This isn't the kind of avalanche problem you can feel under your skis, track or feet, it's far too deep for that. The answer lies in terrain selection.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Wind Slabs
A bit of new snow and wind out of both the southwest and northwest Thursday night into Friday is likely to form fresh wind slabs in exposed terrain features.
Aspects: All aspects.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Dec 27th, 2019 5:00PM
