Avalanche Forecast
Regions: South Rockies.
Confidence
Fair - Timing, track, or intensity of incoming weather system is uncertain on Saturday
Weather Forecast
Friday:Â 5 to 10 cm of precipitation for Friday, winds from the west up to 50 km/h with freezing levels rising to 1000 m.Saturday:Â 10 to 20 cm of precipitation, strong southwesterly winds, freezing level may rise to 1300 m as a pacific frontal system moves through the rockies.Sunday:Â Isolated flurries in the wake of the storm system, freezing levels drop to valley bottom, continued strong winds from the southwest.
Avalanche Summary
Windslabs were triggered by a vehicle and by explosive control in the Eastern part of the region on an E facing aspect slopes. These avalanches were up to 1.5 in size and would have slid on older faceted surface or on low density new snow. A detailed incident report about the Corbin area near miss is available here.
Snowpack Summary
Windslabs continue to develop on lee slopes at ridge tops and in the alpine. The recent storm slabs are settling but may still be sensitive to human triggers, especially where a weak faceted snowpack is underlying the top layer. The facet/crust layer down 80-100 cm at treeline and below treeline and the depth hoar layer in the alpine has been reactive on E aspects. Recent natural and human triggered avalanches on this aspect are a good sign of this instability. When tested and observed, the surface hoar layer down 70 cm is showing signs of healing (grains are rounding and snowpack tests are not as planar as they have been previously). The South Rockies field team has posted a new blog with some good info and pictures about the recent avalanche incident and about current conditions. Click here to read it.
Avalanche Problems
Wind Slabs
Aspects: North, North East, East, South East, South, South West.
Elevations: Alpine.
Likelihood: Possible
Expected Size: 1 - 4
Persistent Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 3 - 6