Avalanche Forecast
Issued: Apr 16th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Loose Wet, Cornices and Deep Persistent Slabs.
Garth Lemke,
On Saturday, Maligne lake road will close at 6am and Icefields parkway will close at 11am from Parkers ridge to Saskatchewan crossing for avalanche control. Check 511 for updates. Avalanches are anticipated on all aspects and elevations.
Summary
Weather Forecast
High pressure continues over Northern BC and Alberta, rapidly establishing spring conditions in the region. Positive daytime temperatures, light winds, strong solar and rising freezing level to as high as 3000m can be expected daily and for the near future.
Snowpack Summary
Spring has Sprung! Expect a crust on solar aspects that will break down early in the day; polar aspects at TL and above may hold dry snow depending on freezing level. Persistent intense solar and warm temps will continue to destabilize snowpack structure increasing the likelihood of natural and human triggered avalanches.
Avalanche Summary
Loose wet and persistent slab avalanche activity observed on all aspects up to size 3 throughout the region. Icefalls, seracs and cornices continue to fail and trigger deeper instabilities.
Confidence
Problems
Loose Wet
Rapidly rising temperatures and strong solar radiation making this a variable but significant problem at all elevations and aspects. Start early and finish early to avoid the highest hazard period, early afternoon through to dark.
- Use extra caution on solar slopes or if the snow is moist or wet.
- Minimize exposure to steep, sun exposed slopes when the solar radiation is strong.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Cornices
Cornices are awake! These features are extremely large, dense and heavy and will likely trigger the deeper instability on the slope below. If you must travel near or below cornices, use good travel techniques and group management to reduce exposure.
- Cornices become weak with daytime heating, so travel early on exposed slopes.
- Pay attention to overhead hazards like cornices which could easily trigger persistent slabs.
Aspects: North, North East, East, South East.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
Forecasters are noting an increase in activity; seeing many larger slides, stepping down to ground or ice. Shallow snowpack areas and solar aspects have increased potential for human triggered and natural avalanches stepping to deeper layers.
- Pay attention to overhead hazards like cornices which could easily trigger the deep persistent slab.
Aspects: All aspects.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Apr 17th, 2021 4:00PM
