Avalanche Forecast
Issued: Mar 1st, 2020 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs and Deep Persistent Slabs.
William Lawson,
Parks Canada
Strong to Extreme alpine winds Monday will continue to develop the wind slab problem at upper elevations. Limit your exposure to overhead hazards like cornices.
Summary
Weather Forecast
Increased in cloud cover Monday with scattered flurries through the day. Alpine wind values will stay sustained at 70-90 KM/H from the SW. Expect freezing levels to 1500m. We could see an additional 5cm of snow accumulation Monday night.
Snowpack Summary
5-10cm of new snow with strong SW winds forming new wind slab in the alpine down to tree line. Watch for buried sun crust on steep solar aspects. The Feb 1 rain crust is down 30-60 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
Direct observations of several small avalanches initiated from strong SW winds were reported Sunday afternoon. Ski hills reported newly formed reactive wind slab specific to immediate lee.
Confidence
Intensity of incoming weather systems is uncertain
Problems
Wind Slabs
New wind slab development in the alpine and exposed areas at tree line. Expect these to be reactive to human triggering in the immediate lee of terrain features.
- Be careful with wind loaded pockets while approaching and climbing ice routes.
- Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
Aspects: All aspects.
Elevations: Alpine, Treeline.
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 (<130cm) 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: Mar 2nd, 2020 4:00PM
