Avalanche Forecast
Issued: Mar 10th, 2020 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs, Cornices and Deep Persistent Slabs.
Mikey,
Avalanche Canada
Intense winds have added another generation of wind slabs. This is a good time to avoid the alpine and open features at treeline. Good skiing can still be found in sheltered areas.
Summary
Confidence
Weather Forecast
Strong to extreme SW winds started on Tuesday and are expected to continue until Wednesday morning, only to diminish to 50km/hr from the West for the rest of Wednesday. Weather models are showing 10-15cm of snow by Wednesday morning with the rest of the day to be a mix of sun and cloud and a high of -9c.
Avalanche Summary
One size 2.5 slab avalanche was observed around 11am on Mount Lawrence Grassi which might have reached the Highline trail. Several other slabs were observed on Mount Rundle, west of EEOR. No other slides were observed along the Spray road but visibility was limited.
Snowpack Summary
Wind, wind and wind slabs.
The forecasters on Tuesday noted strong to extreme SW winds creating intense loading in the alpine and on lee and cross loaded features at treeline. 10-15cm wind slabs at treeline were cracking and breaking with skier traffic. These new wind slabs are growing and are sitting on previous wind slabs from the weekend. It will take several days for all this to sort it self out and settle. Cornices are growing once again.
Terrain and Travel
- Avoid freshly wind loaded terrain features.
- Don't be too cavalier with decision making, storm slabs may remain sensitive to human triggering.
- Avoid lee and cross-loaded terrain.
- Make conservative terrain choices and avoid overhead hazard.
- Extra caution is needed around cornices under the current conditions.
- Be aware of the potential for large avalanches due to the presence of a deep persistent slab.
Problems
Wind Slabs
Wind slabs are everywhere in the Alpine and in lee and cross-loaded terrain at Treeline. Human triggering is very likely.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Cornices
Cornices are large and fragile. If triggered, a cornice failure may trigger a wind slab or a deep persistent slab on the slopes below.
Aspects: North, North East, East, South East, South.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
With the recent loading, this layer may become more active. Triggering is more likely is shallow snowpack areas.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Mar 11th, 2020 4:00PM
