Avalanche Forecast
Issued: Apr 10th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Wind Slabs, Deep Persistent Slabs and Cornices.
Garth Lemke,
The Icefields region remains winter conditions. Good travel and ski conditions are found in sheltered locations. Be cognisant of traveling through lower elevations where large avalanches from above could travel far.
Summary
Weather Forecast
Sunday will be sun, cloud, flurries, trace snow, -9C, light NE winds and valley bottom freezing level. Monday will be similar, -10, light East winds and valley bottom freezing level. Tuesday is sun, clouds, warming up to -3C and 2000m freezing level. There will be a warming trend starting Tuesday.
Snowpack Summary
25cm of new snow arrived Wednesday night at Parkers ridge with much less further North and South. Winds are increasing to moderate speeds forming alpine ridgetop windslabs. The midpack is firm snow over weak basal facets and depth hoar near the ground.
Avalanche Summary
Saturday's Icefield patrol observed several cross loaded features avalanche on PR slope up to size 2.5 likely on Friday. Friday's explosive control work on Parkers slabs produced two size 2.5 hard windslabs burying the road 2m deep. Thursday's Icefield's patrol noted one size 3 on Churchill slide path running full path.
Confidence
The weather pattern is stable on Sunday
Problems
Wind Slabs
There is a lot of snow available for wind transport. Investigate whether this condition rests on a slippery temperature crust having a higher potential for human triggering.
- Use caution in lee and cross-loaded terrain near ridge crests.
- Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
Aspects: North, North East, East.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
Forecasters are noting a slight increase in activity in the past few days. One could say the probability is increasing with either natural or human triggering. Shallow snowpack areas would have the increased potential for human triggering.
- Pay attention to overhead hazards like cornices which could easily trigger the deep persistent slab.
- If triggered the wind slabs may step down to deeper layers resulting in large avalanches.
Aspects: North, North East, East.
Elevations: Alpine.
Likelihood
Expected Size
Cornices
Cornices are large and looming. They are a large trigger on the slope below if they fail or their sheer mass if they hit you would have severe consequences. Potential failures will increase with sun, warmth, or wind.
- Pay attention to overhead hazards like cornices which could easily trigger the deep persistent slab.
Aspects: South West, West, North West.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Apr 11th, 2021 4:00PM
