This is Ontario’s worst wildfire season, early estimates suggest. It’s not over yet.

Wildfires across northern Ontario have torched more of the province’s forest than during any previous year on record, early estimates suggest, with a recent burst of fast-moving wildfires responsible for nearly all of the area burned in just a few days.

The province’s latest numbers suggest fires have burned through more than 7,250 square kilometres of Ontario’s forest, surpassing the previous record set in 2021.

Fire estimates are often revised once officials get a closer look at the devastation, but the initial numbers indicate just how quickly the season has worsened.

“Just seeing how much smoke and how large these fires grew very quickly was just a testament to how intense they were,” said Liam Buchart, a fire weather specialist with the Canadian Forest Service.

Ontario’s season is the latest sign of what scientists have warned could be a new era of extreme wildfire activity in Canada. Climate change, driven by the burning of fossil fuels, contributes to longer wildfires season with more frequent stretches of heat and drought that leave forests primed to burn.

“Year after year, we have these big catastrophic fires in different parts of the country,” said Jennifer Baltzer, a biology professor at Wilfred-Laurier University and the Canada Research Chair for Forest and Global Change.

“The No. 1 issue is climate warming.”

The vast majority of Ontario’s fires burned in the past 10 days. They have forced more than 1,800 people to flee their homes, destroyed several communities and sent plumes of noxious smoke across the province and beyond. All but one of the 13 evacuated communities are First Nations.

Dry conditions percolated for weeks in the north before severe thunderstorms swept across the region and delivered lightning strikes to the parched boreal forest. A scorching heat wave sent temperatures soaring around 15 degrees above seasonal, while winds fanned the flames.

“It’s just the perfect conditions to have those fires spread,” said Anabela Bonada, managing director of climate science at the Intact Centre on Climate Adaptation at the University of Waterloo.

The largest contributor to Ontario’s wildfire season has been the massive 3,188-square-kilometre fire north of Thunder Bay. If that fire alone was a season, it would be the 12th largest recorded in Ontario.

Recent rain and cooler days have helped firefighters make progress, but the hazard remains high and officials expect continued fire activity for the foreseeable future.

“There hasn’t been enough rain in the northwestern part (of Ontario) to really knock things down for the long term,” said Buchart, the fire weather specialist.

Into August, the forecast suggests much of northern Ontario could remain hotter and drier than normal. While conditions may not be as intense as what the region just experienced, “a complete reprieve is not really in the forecast,” Buchart said.

A key way to mitigate more intense fires is to cut planet-warming greenhouse gas emissions, scientists say. Yet, the federal government has in recent months rolled back many of Canada’s climate policies and promised to expand oil and gas production in a stated effort to diversify exports away from the United States.

“We need to have sovereignty, that’s well understood,” said Bonada.

“But if we are not protecting the future or ourselves, if communities are burning down and people are getting sick from extreme heat … then I don’t really see the connection in building a stronger Canada if we don’t have communities to take full advantage of that stronger Canada.”

While climate change has been a major driver of more intense fire seasons, experts point to other underlying issues too. Decades of suppressing naturally occurring fires have led to an accumulation of dead wood and dense undergrowth on the forest floor. The forestry industry’s preference for conifers has in some areas suppressed the growth of more fire-resistant broadleaf deciduous species, such as aspen and birch, said Baltzer, the Wilfred-Laurier professor.

Expanding prescribed burns and support for long-standing Indigenous cultural burning practices can help, experts say. Another widely cited solution is expanded access to FireSmart, a program of actionable steps communities and individuals can take to reduce their wildfire risk.

“The way we think about wildfire needs to shift in the country,” said Bonada.

The preliminary area-burned estimates are compiled by the province’s wildfire agency and shared with Canadian Interagency Forest Fire Centre, a non-profit that co-ordinates firefighting resources across the country. Federal wildfire records — also known as the national burned area composite — date back to 1972 and are derived in part from high-resolution satellite images.

Thick smoke is one of the factors that make it hard for officials to develop precise real-time wildfire estimates. Satellite images will eventually help to identify any water bodies or unburned areas that may have been included in the initial tally.

This report by The Canadian Press was first published July 21, 2026.

Jordan Omstead, The Canadian Press