Avalanche Forecast
Issued: Feb 24th, 2020 4:21PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Deep Persistent Slabs.
conrad janzen,
Parks Canada
Enjoy the great skiing in sheltered areas but use caution in steep wind loaded areas, and make careful route choices in areas with a thin snowpack where the basal weaknesses are more prominent.
Summary
Weather Forecast
Tuesday will be a mix of sun and cloud with a few light flurries beginning in the evening. Alpine temperatures start to rise with highs around -10'C. Moderate W and NW winds are expected at ridge tops through the day with a slight increase in wind speed in the afternoon.
Snowpack Summary
10-20 cm of recent storm snow covers previously formed wind slabs in lee areas, and buried sun crusts on steep solar aspects. The Feb 1 rain crust is down 20-50 cm and present below 1900 m. In thin snow pack areas a dense mid-pack sits over a weak, faceted base. Thick snowpack areas have a denser base with few weaknesses.
Avalanche Summary
A few small explosive and ski cutting triggered wind slabs in the alpine up to size 2 have been reported by the local ski areas in the last couple days. No new natural activity observed in the last 48 hrs. Some sluffing of the new snow in steep terrain near ridge crests and in steep gullies.
Confidence
Due to the number and quality of field observations
Problems
Wind Slabs
Buried wind slabs are present in lee areas of the alpine with isolated pockets of wind slab down into treeline. Cornices have grown very large in recent weeks, so watch your exposure to them carefully.
- Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
- If triggered the wind slabs may step down to deeper layers resulting in large avalanches.
Aspects: All aspects.
Elevations: Alpine.
Likelihood
Expected Size
Deep Persistent Slabs
Avalanche activity on the basal facets has slowed down but the weakness in the snowpack remains a concern. These are hard to predict, but are most likely in areas with a thin snowpack (<150cm) where the basal facets and depth hoar are prominent.
- Pay attention to overhead hazards like cornices which could easily trigger the deep persistent slab.
- Use caution in thin snowpack areas.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Feb 25th, 2020 4:00PM
