Regions
Kootenay Boundary.
Avalanche danger is rising in response to warm temps. On Friday, stay out of the sun, and over the weekend, avoid the rain!
Confidence
Fair - Timing or intensity of solar radiation is uncertain on Friday
Weather Forecast
It is expected to be dry and very warm (freezing level 3000 m) on Friday. Around 15 mm precipitation is expected on Saturday, followed by about 15-25 mm on Sunday. The freezing level during the precip is around 2200 m, falling to 1900 m on Sunday (subject to change). Winds are moderate to strong from the SW.
Avalanche Summary
Apart from small loose wet sluffs triggered by skiers on steep sunny slopes, no new avalanches have been reported in the past several days.
Snowpack Summary
Available snow may shifted by SW winds at high elevations. Lower down the mountain, drizzle has weakened the snow surface layers, adding warmth and weight to the snowpack. The most prominent feature in the snowpack is the thick late-February crust, down 5-20 cm. Limited reports suggest this crust is supportive all the way to ridge crest, "capping" the snowpack and keeping riders from stressing any deeper weak layers. There are still weak layers bellow this crust. As temperatures become very warm over the next couple of days, be alert to whether this supportive capping layer is breaking down. Consequences go up if it does.
Problems
Loose Wet
Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.
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.