Avalanche Forecast
Issued: Mar 17th, 2021 4:00PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Loose Wet, Persistent Slabs and Cornices.
Deryl Kelly,
Icefields Parkway will remain closed for maintenance until Thursday afternoon. Check Alberta511 for updated information.
Summary
Weather Forecast
Approaching front will bring high light clouds which should filter the UV and keep the surface snow cool. Cold overnight recoveries help to maintain the structure of the snowpack. Isolated sun and clouds will mean localized areas of instability.
Snowpack Summary
Warm temps and high solar input has created typical spring like conditions with moist snow on solar aspects from daytime heating, TL and below. Continuing SW winds have redistributed the snow pack, forming hard slabs in the ALP. The mid pack is supportive in deep areas, but shallow snowpack areas are weak and will break down fast with temp swings.
Avalanche Summary
Control operations produced several loose wet slabs on previously controlled terrain.
Confidence
Problems
Loose Wet
Varied sensitivity on solar aspects, likelihood increases on the steepest slopes. It ay nbe possible to trigger deeper instabilities once initiated.
- If triggered the wind slabs may step down to deeper layers resulting in large avalanches.
- Use extra caution on solar slopes or if the snow is moist or wet.
Aspects: All aspects.
Elevations: Treeline, Below Treeline.
Likelihood
Expected Size
Persistent Slabs
More activity noted at this layer, mostly initiated by large loads (cornices) in steep terrain.
- Consider that avalanches may run further than expected as they entrain this loose surface snow.
- Watch for moist surface snow over crust on steeper solar aspects.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Cornices
Cornices can be extremely destructive alone or, may initiate deeper layers in the snowpack below.
- 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, North West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Mar 18th, 2021 4:00PM
