I just finished a week long ski touring camp at Nirvana Pass in western British Columbia near William's Lake. We had excellent mid winter conditions for this part of BC.

The day before we flew in there was a storm that deposited 30 cm of new snow with little wind (March 8). This bonded quickly to the previous surfaces. We had a skier triggered avalanche on the first day, a size 1.5 on a 42° E facing slope, caused by a small 30 cm deep slab that was cut out between tracks near ridgetop, no propagation, which then entrained a sluff that ran 100 m and stopped mid track. Apart from that there was no other reactivity to skier traffic all week. We skied steep open alpine slopes to 45° throughout the week.

Our main concerns were at the beginning of the week, with Moderate Alpine hazard: isolated ridgetop windslabs on East aspects (to size 1.5) as well as afternoon warming creating loose wet hazard on solar aspects to size 2. But after Sunday's warm up (+4 at 1750m) hazard quickly lowered back to Low at all elevations on Tuesday and Wednesday.

Snowpack was 220 cm at our treeline camp elevation (1780 m) and 300-320 cm on the glaciers. In the many wind exposed areas in the alpine the snowpack was considerably thinner. The local heli ski operation was cautioning about a facet/crust Persistent Weak Layer down 40-80 cm in low snowpack areas. We did find this easily but it appears to be solidly bridged by hard (pencil to knife hardness) snow and was not reactive to testing.

Last night we had a bit of a refresh with 3 cm low density powder snow and today was blue skies and sunshine for the flight out. Thank you Nirvana!!!

Regards,
Tom Wolfe
Mountain Guide ACMG/IFMGA
Guided Ski Touring in BC: www.sawback.com/current-trips/