Fresh snow rests on a problematic, persistent slab, don't let good riding lure you into complacency.
Adopt a conservative approach by sticking to low-consequence terrain.
Moderate to gusty winds will likely form wind slabs in localized open terrain and near ridge tops. Watch for newly formed and reactive small slabs as you transition into wind-affected terrain. Slabs in motion may step down to deeper weak layers, resulting in large avalanches.
The Dec 23 weak layer of facets is now down 30 to 60 cm. Numerous and continued remote-triggered avalanches were reported to have failed on this layer in the last few days. Other weak layers are also found deeper within the top 1.5 m of the snowpack. Use extra caution where the snowpack varies from thick to thin, near rock outcrops and convexities. Larger-than-expected avalanches are possible due to the presence of a deeper weak layer. Check out our forecaster blog to learn about how to manage persistent slab problems.
Numerous natural and human-triggered storm and slabs (up to size 2) were reported lately in Revelstoke area.
Continued very large natural and human-triggered persistent slabs (size 2 to 3) failing on a widespread weak layer underneath the storm snow. Some were remotely triggered. Few stepped down to deeper buried weak layers and even down to the ground. Many of these human-triggered avalanches were a surprise to the individuals triggering them.
Although natural avalanche occurrences seem to be tapering off, the next round of precipitation may increase the likelihood of triggering. Please continue to share any observations or photos on the Mountain Information Network.
Up to 15 cm of light snow is now overlying 30 to 60 cm of dense storm snow. Under it, there is a wide variety of previous surfaces; sugary faceted grains, cold unconsolidated snow or a small surface hoar.
New snow has been redistributed at higher elevations on northerly aspects, and fresh slabs may not bond well to older surfaces. At lower elevations, a significant rain crust can be found.
In the upper snowpack, up to three weak layers created earlier in December can be found. Some of these may not exist in all areas of our region. The November weak layer, which will continue to be a concern even after this past storm, can be found anywhere between 75 and 125 cm down. The bottom of the snowpack is generally weak and faceted.
A stronger coastal system will spread moderate snowfalls into the region until later Friday through the weekend. Greater amounts are expected in the western sections. An upper ridge will be bringing widespread subsidence, and therefore fair weather conditions are expected for Monday.
Friday night
Snow, 5 cm except around 10 cm over the Monashees and Cariboos southwesterly ridge winds up to 45 km/h, treeline temperatures -5 °C. Freezing level around 500 m.
Saturday
Light snow, 5 cm except around 10 cm over the Monashees and Cariboos, southerly ridge winds up to 40 km/h, treeline temperatures -5 °C. Freezing level around 750 m.
Sunday
Cloudy, lingering flurries, northwesterly ridge winds up to 20 km/h, treeline temperatures -5 °C. Freezing level around 500 m.
Monday
Mainly sunny, no precipitation, southwesterly ridge winds at 20 km/, treeline temperatures around -8 °C. Freezing level at valley bottom.
More details can be found in the Mountain Weather Forecast.
