Observations of reactive surface hoar have renewed concern for slab avalanche danger in the north of the region. Avalanche danger is generally LOW in the south of the region, requiring normal caution.
Summary
Confidence
Moderate -
Weather Forecast
Sunday looks a bit unsettled with isolated alpine rain showers/flurries. The weather pattern is pretty benign as we enter the work week with scattered cloud cover, seasonal freezing levels and no significant precipitation expected until possibly Wednesday. SUNDAY: Scattered cloud cover, freezing level beginning at 500 m rising to 1600 m throughout the day, light northerly wind, 1 mm of precipitation possible. MONDAY: Scattered cloud cover, freezing level beginning at 1000 m, rising to 1500 m throughout the day, light west/southwest wind, no significant precipitation expected. TUESDAY: Scattered cloud cover, freezing level beginning at 1000 m, rising to 1500 m throughout the day, light west/southwest wind, no significant precipitation expected.
Avalanche Summary
On Friday two size 2 slab avalanches were reported from a north/northeast facing feature between 2100 and 2400 m on the Duffey. The slabs were 20 to 40 cm in depth and failed on surface hoar up to 4 mm in size. Reports from Thursday included one observation of a small storm slab releasing with a ski cut on the steep flank of a couloir in the north of the region. Several other recent natural storm slab releases were observed in the same area, ranging from size 1-2 with crown fracture depths of 10 to 30 cm. North aspects were the most active.
Snowpack Summary
5 to 10 cm of new snow fell Wednesday. In most areas the new snow buried a breakable crust formed by days of warm temperatures and sunshine. In the north of the region polar aspects (those that face north and east) are harboring cold snow and a tricky buried weak layer down 20 to 40 cm below the surface. The layer is widespread in the alpine and at treeline, but it is not everywhere. The layer is composed of surface hoar on polar aspects and a sun crust on solar aspects. This layer continues to produce human triggered avalanches on polar aspects on the Duffey and has not been reported in the south of the region.In the north of the region a weak layer buried mid-February is about 40 to 50 cm below the surface and has been reactive in snowpack tests. The layer is composed of sugary facets, a sun crust on solar aspects, and surface hoar that is present at and below treeline. The snowpack is well settled in the south of the region around the Coquihalla and in Manning Park.Variable winds in the past month have created cornices on many alpine ridgelines. They become touchier as daily temperatures rise and with the strong late winter sun on clear days.
ghelgeson,
Avalanche Canada
