New snow will improve riding conditions, but unpredictable avalanches are possible with buried persistent weak layers. Choosing a conservative terrain is a good strategy.
New snow and strong wind will create fresh slabs, which will be more reactive in leeward terrain and around ridge crests. If triggered, a wind slab may step-down to deeper layers resulting in large avalanches.
Weak layers remain a concern in north-facing terrain where snowpack depth is variable. Avoid steep and shallow rocky features where triggering is possible.
On Monday, two very large persistent slabs were remotely triggered by skiers and a snowcat in the Birkenhead area. They occured on west and east alpine slopes and ran full path. Crowns were 75 to 100 cm and one of them stepped down to the mid-February week layer.
Debris from natural and human-triggered avalanches (such as cornice falls, wind, and storm slabs) from the stormy weekend continues to be reported in the region (up to size 3).
Successive snowfalls will bring up to 20 cm of new snow, forming touchy slabs. This overlies wind-affected snow in leeward terrain at upper elevations and a melt-freeze crust on southerly slopes up to 2000 m. This sits over 80 to 150 cm of settling storm snow from the past week.
The early March weak layer of facets or surface hoar on a crust is now down 100 to 150 cm and present on all aspects except high north-facing slopes. Very large avalanches (size 3 to 3.5) were reported on this layer in the past week.
Weak layers formed in mid-February and late-January are now buried 110 to 190 cm deep.
Thursday Night
Cloudy with 10 to 15 cm of new snow. 30 to 50 km/h southwest ridgetop wind. Treeline temperature -4 °C. Freezing level 1000 m.
Friday
Cloudy with up to 5 cm of new snow. 30 to 40 km/h southwest ridgetop wind. Treeline temperature -2 °C. Freezing level 1200 m.
Saturday
Mix of sun and clouds. 15 to 25 km/h soutwest ridgetop wind. Treeline temperature -2 °C. Freezing level 1200 m.
Sunday
Partly cloudy with isolated flurries. 40 to 60 km/h west ridgetop wind. Treeline temperature +4 °C. Freezing level 2000 m.
More details can be found in the Mountain Weather Forecast.
