With its expansive boreal forests, Canada is vulnerable to wildfires. Northern Ontario alone recorded more than 180 in the first half of 2025. In June, smoke drifting from large fires in Manitoba briefly sent Toronto’s air quality plunging to among worst in the world. Many more forest fires are expected with forecasters predicting a hot, dry summer ahead.
For airports, smoke plumes can complicate their operations and create delays. And while smoky air is still a rare occurrence in Southern Ontario, it’s likely to become more common as wildfires intensify due to climate change.
Here’s how wildfire smoke can affect air travel – and how airports like Toronto Pearson react.
Warning system
One of the few good things about wildfire smoke is that airport managers can see it coming and prepare. Most blazes large enough to impact air travel break out hundreds of kilometres from Toronto Pearson and the enormous clouds of smoke they generate are easily tracked by satellite imagery.
“We have systems that enable us to pull up a smoke map,” says Airport Duty Manager Sonny Parmar. “As soon as we see smoke in our weather forecasts, we check with Environment Canada for air-quality alerts.” If conditions are expected to deteriorate, Pearson’s operations centre issues advisories to all companies operating at the airport.
Protecting ground staff
Ground staff, including baggage handlers and maintenance teams, spend much of their day outdoors in physically demanding roles. When poor air quality is expected, additional safety protocols are implemented. While these differ among the airlines and handling companies that employ most ground crew, they usually involve measures such as longer rest breaks and minimizing limit time outdoors.
Finding clear skies
Airline dispatchers monitor smoke plumes closely and will route flights to avoid dense smoke or active fires. While wildfire smoke isn’t as hazardous as volcanic ash – which contains tiny pieces of rock and glass that force flights to stay on the ground – it can still coat aircraft surfaces with soot, increasing maintenance requirements. Smoke detours aren’t usually perceptible to passengers, but if a large area must be avoided, it can add a few minutes to flight times.
Hazy delays
Occasionally, smoke is thick enough to reduce sight distance. Pilots are trained to land planes in low visibility, but air traffic controllers will usually increase spacing between arriving aircraft for added safety. This lowers the number of planes that can land per hour, potentially leading to delays and cancellations – especially if the conditions persist.
“Every plane takes a minute or two longer to land, taxi and offload. Over time that adds up,” Parmar explains. Although departures are less affected by low visibility, they can also be disrupted if incoming planes are delayed.
When wildfire smoke affects the Toronto area, passengers should check their flight’s status with their airline or on Toronto Pearson’s online departures board.