Check out our Forecasters' Blog about factoring extreme cold into your trip plans. A small avalanche involvement could be a big problem in these temperatures.
Light new snow and elevated, shifting winds in the early week created new wind slabs to manage on a range of aspects. Continuing northerly winds may keep slab formation in progress on Thursday.
Observations have been limited but reports from the early part of the week included:
-A natural size 2.5 (large) wind slab on a southwest aspect at treeline just north of Powder King on Tuesday.
-A few natural and ski cut size 1-2 wind slabs on southwest and northeast aspects in the alpine and treeline in Pine Pass, near Loos, and above Quesnel Lake on Sunday and Monday.
The mix of aspects here may already be telling us about reverse loading from north winds.
About 10-15 cm of new snow fell in the region in the early week. It mainly buried wind-affected surfaces in exposed areas at elevation and otherwise added to about 30 cm of settling recent snow. Collectively, this snow overlies a crust up to 1400 m on all aspects, but it may sit over a weak layer of surface hoar in sheltered areas.
Two more layers of surface hoar can be found in the top meter of the snowpack at treeline. The likelihood of triggering these layers is low, with the possible exception being shallow, rocky areas at upper treeline.
The current snowpack has considerable variation in structure and depths across the region and is shallow for this time of year.
Check out this MIN report from Sugarbowl.
Wednesday night
Clearing, still thin overcast. Northeast wind 30-50 km/h.
Thursday
Mainly sunny or thin overcast. Northeast wind 35-55 km/h. Treeline temperature -32°C.
Friday
Sunny. North wind 5-15 km/h. Treeline temperature -30 to -35°C.
Saturday
Sunny. Variable alpine wind 5-10 km/h. Treeline temperature -25°C to -30°C.
More details can be found in the Mountain Weather Forecast.
