Avalanche Forecast
Regions: Little Yoho.
The basal depth hoar can be heard jing, jing, jingling in your snow pit. Conservative terrain choices are important to stay safe when dealing with this overall weak snowpack. Happy holidays. SH
Weather Forecast
The very windy alpine conditions will continue Thurs and Fri. with strong to extreme westerlies. Light snow amounts of 5-10cm expected over the next 2 days and freezing levels to valley bottom.
Snowpack Summary
5-10cm of new snow in the W tapers to nothing in the E. A variety of surface weaknesses including widespread windslabs in the ALP and isolated surface hoar at TL & BTL sit on a generally weak snowpack. The real concern is the facet/depth hoar/crust combo at the base of the snowpack which been triggered by light loads recently and can't be trusted.
Avalanche Summary
A size 2.5 was observed 2 days ago on a N aspect of Mt. Fairview. It was initiated as a wind-induced spindrift avalanche which pulled out a slab that failed near the ground. This is indicative of the widespread basal weakness present in the snowpack.
Confidence
Due to the quality of field observations on Wednesday
Avalanche Problems
Deep Persistent Slabs
Full depth, human triggered avalanches are likely in specific features. This basal crust/depth hoar problem will last for a while to come.
- Avoid areas with overhead hazard.
- Avoid steep, open slopes.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Likely
Expected Size: 2 - 3
Wind Slabs
Windslabs are prevalent in many areas at upper elevations, and any new snow and wind will contribute to their formation. Once triggered in steeper terrain, these have been seen to trigger deeper releases on the basal weakness.
- Be aware of the potential for full depth avalanches due to weak layers at the base of the snowpack.
- Use caution in lee areas in the alpine. Recent wind loading have created wind slabs.
Aspects: North, North East, East, South East, South.
Elevations: Alpine, Treeline.
Likelihood: Possible - Likely
Expected Size: 1 - 2