Confidence
Fair - Due to variable snowpack conditions
Weather Forecast
The ridge of high pressure should re-emerge for tuesday bringing clear skies for one more day. On Wednesday, expect increased cloud throughout the day. Trace amounts of snow are possible on Thursday. Freezing levels should rise gradually throughout the forecast period to 1000m on Thursday. Winds will be light and southerly switching to northwesterly by thursday.
Avalanche Summary
On Saturday a skier was injured in an avalanche near Kimberley. The size 2.5 slab released on a west facing, cross-loaded alpine slope. The crown varied in height, but was up to 1m deep. For more details, check-out the following link to our Incident Report Database: https://avalanche.ca/cac/library/incident-report-database/view/4a015304-42f6-4cc1-91e9-5450e2deec8f On Sunday explosives-controlled avalanches to size 3 were reported in the region in steep alpine terrain (north and west aspects). Some of these avalanches released within the mid-pack while 2 released at the ground.
Snowpack Summary
Cooling has helped the snowpack to gain some strength since the warming on the weekend and a crusts have now developed on most slopes that saw direct sun.On shaded aspects the upper snowpack is also well settled. Below this sits a fairly well bonded mid-pack. There are, however, a few exceptions. The Jan. 13th SH/FC combo has been reactive in the north of the region. As well, the mid December facet/surface hoar layer is buried approx. 80 cm on the east side and 200+ cm on the west side. Operators are talking less about this layer as of late. There are also basal facets at the ground which have continued to be reactive, especially in the thin snowpack parts of the region. Snowpack depths at 2000m sit near 2m deep. If you're traveling around the mountains, it's a good time to take notice of what layers are developing (surface hoar/ crusts) that may become an issue once buried.
Problems
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.
Cornices
Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.