Avalanche Forecast
Regions: Sea To Sky.
Confidence
Fair
Weather Forecast
Synopsis: Lingering flurries are likely on Monday in the wake of a frontal system. A ridge of high pressure begins to build in resulting in clearing and drier conditions for Tuesday and Wednesday. Monday: Flurries ending early, then cloudy with sunny breaks. The freezing level is around 300 m. Winds are generally light. Tuesday: A mix of sun and cloud. The freezing level jumps as high as 2500 m with treeline temps ranging from +3 to +6. Winds are light and variable. Wednesday: A mix of sun and cloud. The freezing level jumps remains near 2500 m with treeline temps ranging from +4 to +8. Winds are light and variable.
Avalanche Summary
There was one new report of a size 2 remotely triggered slab avalanche in the Whistler backcountry. The slab depth was reported to be approximately 1.5 m deep, likely failing on a facet/crust combo. There was also a report of a size 2 accidentally skier triggered avalanche in the Blackcomb backcountry on Friday. Check out Wayne Flann's Avalanche Blog for photos of both of these incidents. Other observers in the region reported no new natural avalanches and no results with ski testing. It's likely becoming more difficult to trigger slab avalanches, but it's certainly still possible and if triggered it will likely be a deep avalanche with real potential for wide propagation.
Snowpack Summary
20-30 cm of low density snow has fallen in the past 2 days with light winds forming fresh thin wind slabs near ridge crests. The prominent mid-February weakness, which is primarily a facet/crust combo (with surface hoar in some areas), is now 70-150 cm deep depending on wind exposure. Recent snowpack tests give variable results on this layer, but some observers are still reporting sudden "pops or drops" shears and are experiencing significant whumpfing. Previous strong winds have created wind slabs in exposed lee and cross-loaded terrain. Relatively thin wind slabs have the potential to trigger the deeper mid-Feb weakness. The mid and lower snowpack are generally strong and well-settled. Basal facets and depth hoar are likely to exist in some parts of the region; however, skier triggering has become unlikely.
Avalanche Problems
Persistent Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Possible - Likely
Expected Size: 2 - 5
Wind Slabs
Aspects: North, North East, East, South East, South.
Elevations: Alpine, Treeline.
Likelihood: Likely
Expected Size: 1 - 4