Start in mellow terrain and watch for signs of instability like shooting cracks or recent avalanches.
New snow and wind may cause a recently buried weak layer to reach its tipping point.
Human triggerable wind slabs may be found below ridgetops and in cross-loaded terrain. A layer of surface hoar buried in early January may be reaching a tipping point as the load above it increases, which could lead to wide propagations.
On Thursday, several small to large (up to size 2) natural and human triggered wind slab and cornice avalanches were reported, as well as natural loose dry avalanches, and sluffing with rider traffic in steep terrain.
Recently, there were reports of glide cracks opening up and glide slab avalanches up to size 2. Notably more than usual. This problem may exist only in these isolated features, but we'll see if a pattern emerges.
Moderate winds may have formed wind slabs on lee slopes at treeline and above. A shift from southwest to northwest wind means that wind loading will be happening on different slopes versus Wednesday and Thursday.
In sheltered terrain, 20 to 40 cm of settling snow sits on a layer of weak, feathery crystals up to 10 mm in size (surface hoar), possibly even into the alpine. In some places this layer may include a crust due to solar effect or very high humidity.
A crust/facet/surface hoar layer (buried in early December) may be found 90 to 160 cm deep. It was previously most active south of Highway 5, but it no longer seems to be an avalanche problem for this forecast area.
Friday Night
Cloudy with 0 to 5 cm of snow. 40 to 70 km/h west ridgetop wind. Treeline temperature -6 °C.
Saturday
Cloudy with 1 to 3 cm of snow north of Highway 1, 5 to 10 cm south of Highway 1. 30 to 60 km/h west ridgetop wind, decreasing through the day. Treeline temperature -6 °C.
Sunday
Mostly cloudy with up to 2 cm of snow. 20 to 30 km/h northwest ridgetop wind. Treeline temperature -9 °C.
Monday
Mostly sunny. 20 to 30 km/h northwest ridgetop wind. Possible temperature inversion above 2000 m. Treeline temperature -7 °C.
More details can be found in the Mountain Weather Forecast.
