Regions
Kootenay Boundary.
Wind slabs may be lingering in the alpine. Use extra caution in wind loaded terrain. Loose sluffing is also possible from steep sun-exposed slopes.
Weather Forecast
The ridge of high pressure continues to produce clear and dry conditions. Thursday should be mostly sunny with cloudy periods. Freezing levels are expected to reach around 1500m as a warming trend begins heading into the weekend. Alpine winds on Thursday are expected to be moderate-to-strong from the NW. On Friday, similar conditions are expected with a mix of sun and cloud and moderate-to-strong NW winds in the alpine. However, freezing levels may reach over 2000m. On Saturday, freezing levels are forecast to remain around 2000m and increased cloud cover is expected.
Avalanche Summary
On Tuesday there were reports of small wind slabs being triggered by explosives. Also, natural sun-triggered sluffing of the new snow was reported from steep sun-exposed slopes. On Thursday it should remain possible to trigger thin pockets of wind slabs in exposed leeward terrain features.
Snowpack Summary
Shady and sheltered slopes have 5-15 cm of recent new snow. Thin wind slabs have formed in exposed lee terrain features from ongoing NW-NE winds. Steep sun-exposed slopes likely have a thin new sun crust on the surface. The most prominent feature in the snowpack is a thick crust, down 5-30 cm. This crust is supportive all the way to ridge crest and is effectively "capping" the snowpack, keeping riders from stressing any deeper weak layers. There are still weak layers below this crust that we'll continue to monitor, but for now these layers are dormant. We would likely need significant warming and/or heavy loading to re-activate them.
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.