A smoke advisory from Environment Canada on Tuesday morning was quickly lifted, but air quality in Calgary will likely deteriorate as winds from B.C. flow into the city later this week.
The air quality index in Calgary reached 7 on Tuesday morning, as smoke from wildfires in the Northwest Territories drifted into the city. However, by the time it arrived in Calgary, surface-level winds in the city helped clear the sky.
However, northern cities, including Edmonton, were choked with smoke, with that city’s air quality index touching 9, or high risk.
Edmontonians who are coughing or have a sore throat are asked to consider “reducing or rescheduling strenuous activities outdoors.”
The source of smoke in Alberta skies is about to change.
“Now our winds have shifted,” said Janelle Gergely, meteorologist at Environment Canada.
It means Calgary is poised to receive air from the Pacific Northwest, which will bring warmer weather and smoke from wildfires raging in B.C.
As of Tuesday, four wildfires are burning out of control in the western province, posing a risk to public safety. Three of them are west of Kimberley, prompting evacuation orders for roughly 9,000 nearby residents.
Meanwhile, a large fire near Boston Bar — an unincorporated community along Highway 1 in the Fraser Canyon, about 45 kilometres north of Hope — has also sparked several evacuation orders and alerts.
The shift in winds is due to what meteorologists call Rossby waves, which are movements of the Earth’s atmosphere that form high-altitude winds, such as the jet stream — a rapid, narrow band of air current high in the atmosphere that also marks the separation between warmer and colder air masses.
Predicting smoke is a challenge for meteorologists, Gergely said.
“If all the fires went out, which they likely won’t, then we wouldn’t see the smoke,” she added. “All I can say is there’s the possibility that smoke could be moving over the Rockies from a different source.”
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