Avalanche Forecast
Issued: Mar 12th, 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.
Stephen Holeczi,
Parks Canada
Excellent ski quality and coverage right now. Keep the avalanche problems in mind when considering exposing yourself to committing terrain.
Summary
Weather Forecast
An East/ South East flow will develop Friday and winds will increase into the moderate range. 5cm is possible Thursday night and very light amounts for Friday . Temperatures will decrease throughout the day and we will be in a deep freeze by Saturday with temperatures from -20 to -25C.
Snowpack Summary
15-25cm of snow over the last 2 days has been transported by moderate winds at upper elevations creating wind slabs on immediate lee slopes. On steep solar a thin crust has formed on the surface. We continue to monitor the deep, weak facetted snow in the shallower areas of the park.
Avalanche Summary
Direct observation of a natural size 3 cornice release from the postcard face on Cascade mountain Wednesday. The avalanche ran 1700m to the top of the run out zone. Another size 2 wind slab was observed from the last 24 hours on a S facing slope at 2300m on Observation Peak. Some sloughing has been observed in steep terrain.
Confidence
Problems
Wind Slabs
It is possible to trigger a wind slab in alpine and treeline features exposed to the wind, especially at ridge top. Forecast E/SE winds could mean reverse loading on ridge crests.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
This problem is the sleeping giant who remains asleep right now until a significant change wakes them up again. Avalanches are most likely in areas with a thin snowpack (<130cm) where the basal facets and depth hoar are the weakest.
- Be aware of thin areas that may propogate to deeper instabilites.
- Pay attention to overhead hazards like cornices which could trigger the deep persistent slab.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Mar 13th, 2020 4:00PM
