Avalanche Forecast
Regions: Coquihalla, Harrison-Fraser, Manning, Skagit.
Your travel Sunday likely comes in the wake of a natural avalanche cycle. Bring a conservative, 'assessment' mindset to investigate the aftermath. Human triggering is a serious concern.
Confidence
Low
Avalanche Summary
Some loose wet natural activity has been reported at lower elevations. A natural avalanche cycle is expected Saturday night and human triggering will be a serious concern for Sunday.
Snowpack Summary
An uncertain 20 - 40 cm of wet, heavy new snow may accumulate by end of day Sunday, adding to 20 cm of similarly upside-down storm snow that has fallen with variable wind. In sheltered terrain this new snow may overlie a problematic layer of faceted snow or surface hoar. In exposed terrain it may have been blown away to expose the underlying crust.
In the Manning Park area there has been less new snow and significantly less wind.
A crust from December is buried 80 to 140 cm deep, with facets around it in shallow snowpack areas. Otherwise, the lower snowpack is strong and bonded.
Weather Summary
Saturday night
Cloudy with 20 - 50 mm of mixed precipitation producing a possible 10 - 30 cm of alpine snow. 40 to 60 km/h southwest ridgetop wind. Freezing level 1700 m - 1900 m.
Sunday
Cloudy with 5 - 15 mm of mixed precipitation bringing up to 10 cm of alpine snow. 20 to 30 km/h southwest ridgetop wind. Freezing level 1700 m.
Monday
A mix of sun and cloud after 15 to 25 mm of mixed precipitation overnight produces 5 - 15 cm of alpine snow. 20 to 40 km/h southwest ridgetop wind. Freezing level rising to 1800 m in the afternoon.
Tuesday
Cloudy with scattered wet flurries bringing 5 - 10 cm of new snow, including overnight, greatest in the alpine. 40 - 50 km/h southwest ridgetop wind. Freezing level 1700 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Continue to make conservative terrain choices while the storm snow settles and stabilizes.
- Closely monitor how the new snow is bonding to the old surface.
- Be careful as you transition into wind-affected terrain.
Avalanche Problems
Storm Slabs
Warming temperatures, strong winds, and new snow have been forming a storm slab problem above the snowline. Take extra caution when transitioning into wind affected terrain.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Very Likely
Expected Size: 1 - 2.5
Loose Wet
Triggers in steep terrain may still be capable of producing wet snow releases before a surface crust forms and free water drains away.
Aspects: All aspects.
Elevations: Treeline, Below Treeline.
Likelihood: Possible
Expected Size: 1 - 2