Elevated avalanche risk in Banff National Park and K Country due to heavy snowfall

Mountain safety officials in Banff National Park, Jasper National Park, Kananaskis Country and a number of other national parks west of Calgary are putting out warnings about elevated avalanche risks after recent heavy snowfall.

According to Parks Canada, Banff and Jasper national parks are sitting at a "high" avalanche risk (Level 4) in the alpine elevation, and at "considerable" risk (Level 3) in and below the treeline.

Danger ratings are based on a five-level scale, with 1 being low risk and 5 being extreme risk.

On Friday afternoon, RCMP confirmed one person died after a human-triggered avalanche near Lake Louise.

Banff National Park has received 30-90 centimetres of snow in the past five days in some places — that has nearly doubled the snowpack in areas like Bow Summit. This can mean an increased risk of both natural and human-triggered avalanches.

Alex Lawson, a visitor safety technician with Banff National Park, said they're advising people to avoid avalanche terrain for now.

"There is a contrast throughout the park of what people might be encountering for snow amounts," he said. "But in areas where we did receive the bulk of the snow, the avalanche danger is at all elevations."

Lawson said the new snow is a "significant load" that's layered on an "all-time low snowpack," which can trigger more problems.

In addition to seeing a significant number of natural avalanches, Lawson said the park is receiving daily reports of human-triggered avalanches in the area — some directly triggered and others remotely. 

Those remote avalanches are initiated by the load of a human on the slopes but occur elsewhere, like an adjacent slope.

Earlier weak snowpack contributing to risk

According to Kananaskis Mountain Rescue, the avalanche risk in the region is "considerable" in and above the treeline, and "moderate" below. 

Mike Koppang, mountain rescue specialist for the Kananaskis region, said the new snow that's now sitting on top of some weaker snowpack layers increases the risk of sliding.

"It's safe to say this was our largest snow of the season," Koppang said. "We did also see sort of 40-60 centimetres of snow here, and it fell on a variety of different weak layers from crusts to … some weaker crystals that developed in the cooler part of the winter."

Weak layers within the snowpack are composed of snow crystals that are poorly bonded with the snow above or below them, according to Avalanche Canada.

The fracturing of a weak layer can result in an avalanche.

Koppang said the Kananaskis region is seeing avalanches that are running "full pass," starting in the alpine through the treeline down to the valley floor.

Staying safe on and off the slopes

These warnings aren't the first of the season. About two weeks ago, Avalanche Canada issued a special public avalanche warning for most regions in British Columbia and western Alberta.

"The snowpack is weak and it's really susceptible to human-triggered avalanches, so pump the brakes, [and] stay very, very mellow if at all interacting with avalanche terrain," Koppang said.

Some safety recommendations include having proper avalanche safety training and gear, travelling in groups and always checking forecasts and avalanche bulletins before heading out.

"We advise people to stay out of avalanche terrain until the snowpack can get used to this load," Lawson said. "Since we've been continually getting snow, it's not healing right away. It's going to take some time."

"[In] parts of our region, it might be weeks before we're back into a snowpack where we feel confident entering … bigger slopes and more significant avalanche terrain." 

Lawson warned that while the risk will likely decrease over the coming days, backcountry enthusiasts shouldn't become too confident in the snowpack. That's because while the risk of natural avalanches will decrease, he warned the risk of human-triggered avalanches won't go away.

Koppang and Lawson recommend checking avalanche.ca for more information.