Avalanche danger will increase as new snow and wind form fresh wind slabs at upper elevations. Don't forget about a buried weak layer that remains triggerable around treeline.
New snow and wind are building fresh and reactive wind slabs in lee terrain features at upper elevations. Features where wind deposited snow tends to accumulate include just below ridge crests and roll overs and on the lee side of rib features.
A couple of layers of surface hoar exist in the upper snowpack, sometimes in combination with a crust. The problem and associated avalanche activity have been spotty both across terrain features and across the region. The best approach is to employ travel habits to manage it unless you can rule it out in your riding area.
Monday night: Snowfall 5-10 cm. Strong southwest wind. Alpine temperature around -2 °C. Freezing level rising to 1500 m.
Tuesday: Snowfall 5-10 cm. Strong southwest wind. Alpine high around -1 °C. Freezing level 1700 m.
Wednesday: Overnight snowfall 5-10 cm then clearing. Moderate southwest wind. Alpine high around -6 °C. Freezing level 1000 m.
Thursday: A mix of sun and cloud. Moderate south wind. Alpine high around -5 °C. Freezing level 1200 m.
On Sunday, natural cornice-triggered wind slab avalanches were reported up to size 2.
Persistent slab avalanches on a weak layer of surface hoar crystals buried in late February have surprised a few people in the last week with quickly propagating accidental and remote triggers. The layer has been most active on north-northeast aspects between 1200 and 1600 m in areas north of Hazelton.
Strong winds have blown new and recent snow into wind slabs at upper elevations.
A few sun crust and surface hoar layers exist in the upper snowpack. The most concerning of which is a layer of surface hoar crystals found 30-45 cm deep. It has a tendency to surprise riders given it's spotty distribution, most often found on north to east aspects around treeline.
A thick crust formed in mid-February is now buried 50-80 cm deep. It is unlikely to present an avalanche problem under the current conditions and in fact bridges any underlying instabilities in the lower snowpack.
