Avalanche Forecast
Regions: Haines Pass.
Recent large, natural avalanche activity indicates an unstable snowpack in northerly alpine terrain.
Stick to lower-angled slopes and avoid overhead hazard.
Confidence
Moderate
Avalanche Summary
On Sunday in Haines Pass, several large natural persistent slab avalanches were reported from northerly alpine terrain. See full details in this MIN report.
Northerly alpine terrain will continue to be the main concern on Tuesday for both persistent slab avalanches and newly formed, reactive wind slabs.
Thank you for sharing your observations!
Snowpack Summary
Surface hoar (5-10 mm) has been reported to ridgetop in the Haines Pass.
At lower elevations and on south aspects, a crust can be found on the surface. On higher north aspects, new snow and southerly wind may continue to form wind slabs.
A weak layer of facets on a crust down 45 cm has produced recent, large natural avalanches in Haines Pass. Check out this MIN for details.
Weather Summary
Monday night
Cloudy with up to 5 cm of new snow. 30 to 50 km/h southwest ridgetop wind. Treeline temperature -4 °C. Freezing level 600 m.
Tuesday
Cloudy with up to 3 cm of new snow. 30 to 40 km/h southwest ridgetop wind. Treeline temperature -1 °C. Freezing level rises to 1000 m.
Wednesday
Cloudy with up to 5 cm of new snow. 40 to 70 km/h south ridgetop wind. Treeline temperature 0 °C. Freezing level rises to 1200 m.
Thrusday
Cloudy with up to 5 cm of new snow. 30 to 50 km/h south ridgetop wind. Treeline temperature 0 °C. Freezing level rises to 1200 m.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Be aware of the potential for large avalanches due to buried weak layers.
- Cornice failures could trigger large and destructive avalanches.
- Watch for newly formed and reactive wind slabs as you transition into wind-affected terrain.
Avalanche Problems
Persistent Slabs
In the past few days, several large, widely propagating natural avalanches have been observed in northerly alpine terrain. We suspect these avalanches failed on a buried facet/crust layer.
Aspects: North, North East, East, West, North West.
Elevations: Alpine.
Likelihood: Possible
Expected Size: 1.5 - 3
Wind Slabs
Recent and newly formed wind slabs may continue to be reactive on Tuesday.
Aspects: North, North East, East, West, North West.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 1 - 2