Some thin new wind slabs are expected to develop with the forecast new snow. New snow is not expected to bond well to the old hard surface where surface hoar and/or facets exist.
Confidence
Fair - Timing, track, or intensity of incoming weather system is uncertain
Weather Forecast
Overnight and Wednesday: Overcast with light Southwest winds and 3-5 cm of snow above about 700 metres elevation. Freezing level is expected to continue to lower during the day down to about 500 metres as light precipitation continues.Thursday: Continued light precipitation bringing 3-5 cm of snow to all elevations. Moderate Northwest winds becoming light Westerly.Friday: Gradual clearing during the day as the precipitation ends. Freezing level expected to remain at valley bottoms as cooler arctic air moves in from the North.
Avalanche Summary
No new avalanches reported.
Snowpack Summary
Below freezing temperatures have created a solid melt-freeze crust at all elevations and on most aspects. Sheltered North aspects in the alpine may have stayed dry and now have facetted surface snow. New snow may not bond to the old surface where surface hoar has grown at and below treeline. In the alpine the new snow may not bond to the crust depending on the timing of the cooling. There continues to be a concern for deeply buried layers of weak facetted crystals, this is mostly a concern on slopes with a shallow and variable snowpack in the Duffey Lake and Chilcotin areas.
Problems
Deep Persistent Slabs
Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.