Avalanche Forecast
Issued: Mar 6th, 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.
JMackenzie,
Avalanche Canada
Avoid avalanche terrain. An avalanche cycle is ongoing.
Summary
Confidence
Weather Forecast
Heavy snow is expected on Saturday with as much as 30cm possible by the end of day. Temperatures will fall with the approaching cold front with midday temps near -10. Winds will also decrease slightly with light to moderate SW winds.The storm ends late Saturday bringing a mix of sun and cloud on Sunday.
Avalanche Summary
Ski cutting produces loose dry avalanches up to size 1.0 in steep Treeline terrain. Some small slabs were also triggered in this elevation band on small, non-consequential test features. Visibility was extremely limited in heavy snow all day, but we suspect there is a natural avalanche cycle ongoing.
Snowpack Summary
Heavy snow today and last night has deposited up to 15cm of fresh snow in the past 24 to 36 hours. The recent storm snow is settling and now consists of 40 to 60cm in the past week. The new snow does not appear to be bonding well and is sluffing easily in steeper terrain with ski cutting. In the Alpine and open areas at Treeline there are widespread wind slabs of varying depths and densities. The forecast team today observed cracking and small releases while ski testing in small steep convex features at 2300m.
Terrain and Travel
- Avoid freshly wind loaded terrain features.
- Be aware of the potential for large avalanches due to the presence of a deep persistent slab.
- Avoid lee and cross-loaded terrain.
- Be cautious of sluffing.
- Extra caution is needed around cornices under the current conditions.
- Choose simple, low-angle, well supported terrain without convexities.
- Make conservative terrain choices and avoid overhead hazard.
Problems
Wind Slabs
Wind slabs are everywhere at Treeline and above. These slabs are sensitive to human triggering, and a natural avalanche cycle is occurring.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Cornices
Cornices are large and easily triggered. A large cornice failure could trigger a wind slab or a deep persistent slab on the underlying slope. Avoid all exposure to cornices.
Aspects: North, North East, East, South East, South.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
This problem is still with us. Thin snowpack areas are generally more concerning, as this is where triggering the deep instability is more likely.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Mar 7th, 2020 4:00PM
