Avalanche Forecast
Issued: Feb 17th, 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.
deryl kelly,
Parks Canada
Human triggering is possible in areas where windslab is present. This WILL trigger the deep instability, especially in areas where there is significant spacial variability and wind effect.
Summary
Weather Forecast
Fair weather approaches! A surface ridge, from the north and will push isolated flurries through the northern front ranges Monday; finally clearing over the day Tuesday. Broken sun and an alpine high temperature of -12 C. Wind, NW 10 km/h gusting to 30 km/h.
Find the Alberta Rockies weather synopsis here: Mountain Weather Forecast
Snowpack Summary
Variable strength windslab on the surface. Pronounced cornice development on northerly aspects and cross loaded features treeline and above. The mid-pack is bridging the deeper basal facets and depth hoar in some locations.
Average HS at treeline: ~180cm.
Avalanche Summary
"The Beast has awakened!" Experienced back-country users remotely triggered a very large avalanche (sz 4) on Whistlers Peak yesterday. The pair observed significant wind effect in the area and unknowingly triggered the windslab from 100m away, which then initiated the entire season's snowpack on the deep persistent layer. Further details here: MIN
Confidence
Intensity of incoming weather systems is uncertain on Wednesday
Problems
Wind Slabs
Wind slabs are widespread through the region with new and previous loading in lee features. Sensitivity will vary with local loading and wind patterns.
- Assess start zones carefully and use safe travel techniques.
- Watch for pockets of hard windslab in steep alpine terrain features..
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
Shallow snowpack areas, windslabs and/or large triggers such as cornice failures could trigger this deep layer. The consequences of triggering will likely be severe!
- If triggered the wind slabs may step down to deeper layers resulting in large avalanches.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Feb 18th, 2020 4:00PM
