Avoid all avalanche terrain during periods of high hazard.
Many close calls occurred this week, and very large avalanches are expected to continue.
Weak layers remain a concern, especially in north-facing terrain where snowpack depth is variable. Avoid steep and shallow rocky features where human-triggering is possible.
Storm snow and strong southwest winds will form touchy storm slabs. Expect to find deeper and more reactive deposits on north- and east-facing slopes.
Storm slabs may step-down to deeper layers resulting in very large avalanches.
Rain-on-snow and warm temperatures will rapidly destabilize the snowpack, with 1750 m freezing levels and up to 30 mm expected.
Saturday, a very large avalanche was snowmobile triggered near Wendy Thompson.
Friday, skiers remotely triggered this very large avalanche near Vantage Peak. Explosive control produced four size 2.5 persistent slab avalanches on northwest alpine slopes.
Monday 18th, two very large persistent slabs were remotely triggered in the Birkenhead area. They occurred on west and east alpine slopes 75 to 100 cm deep, and one of them stepped down to the mid-February week layer.
25 to 40 mm of new snow is expected, falling as rain below 1500m. Snow will be redistributed into deeper, more reactive deposits on north- and east-facing slopes by moderate to strong southwesterly winds.
A melt-freeze crust on southerly slopes up to 2000 m exists about 60 cm deep. This sits over 80 to 150 cm of settled snow.
The early March weak layer of facets or surface hoar on a crust is now down 100 to 170 cm and is present on all aspects except high north-facing slopes. Very large avalanches (size 3 to 3.5) were reported on this layer this past week.
Weak layers formed in mid-February and late-January are now buried 180 to 250 cm deep.
Sunday Night
Cloudy with 5 to 10 mm, falling as snow above 1400 m. 30 to 60 km/h southwest ridgetop winds. Treeline temperature -2 °C.
Monday
Cloudy with 10 to 20 mm, falling as snow above 1500 m. 20 to 40 km/h southwest ridgetop winds. Treeline temperature -1 °C.
Tuesday
Cloudy with trace precipitation. 30 km/h south ridgetop winds. Treeline temperature 3 °C.
Wednesday
Cloudy with trace precipitation. 30 km/h south ridgetop winds. Treeline temperature 4 °C.
More details can be found in the Mountain Weather Forecast.
