Avalanche Forecast
Regions: Little Yoho.
After an extended spell with no change and soft surface snow in this region, rising winds on Tuesday and into Wednesday are expected to change the surface snow conditions and briefly raise the avalanche danger. Monitor the texture of the snow carefully and avoid wind-loaded areas in leeward terrain or gully walls (cross-loading).
Confidence
Moderate
Avalanche Summary
No observations were reported from this region on Tuesday, but in adjacent regions, Only small (size 1) windslabs and dry loose (sluffs) were observed today, but lots of blowing snow and spindrift was circulating.
Snowpack Summary
Building west winds have blown the surface snow into the lee side of ridge crests and cross-loaded gully features, but slab formation has been limited due to the dry, faceted nature of the blowing snow. The mid-pack is generally strong but a weak crust/facet layer can be found near the ground in shallow snowpack areas. At treeline, average snowpack depths are 120-150 cm. The snowpack here is generally deeper and more consolidated than areas further east in the BYK region.
Weather Summary
The wind has finally arrived and will continue to blow strong (60-80 km/hr) from the SW until mid-day on Wednesday when it should taper. Expect up to 5 centimetres of new snow on Wednesday morning, and temperatures will remain cool, from -5 to -12. Overall an unstable few days ahead with wind as the dominant feature and small amounts of new snow expected.
Terrain and Travel Advice
- Pay attention to the wind; once it starts to blow, sensitive wind slabs are likely to form.
- Avoid shallow, rocky areas where the snowpack transitions from thick to thin.
Avalanche Problems
Wind Slabs
Winds reaching 70 km/hr were recorded on Tuesday with the forecast calling for continued strong winds until mid-day Wednesday. This will create windslabs. Initial reports indicate this is primarily in alpine areas, but watch as they may develop at treeline also.
Aspects: North, North East, East, South East, South.
Elevations: Alpine, Treeline.
Likelihood: Likely
Expected Size: 1 - 2
Deep Persistent Slabs
In shallow snowpack areas (eg. windblown ridges or crossloaded slopes), weak facets and depth hoar associated with old crusts can be found near the base of the snowpack. Avoiding thin areas will help limit your exposure to this problem.
Aspects: All aspects.
Elevations: Alpine.
Likelihood: Unlikely - Possible
Expected Size: 1.5 - 3