Wildfires raging across northwestern Ontario, Canada, have blanketed major cities in thick smog, with Toronto recording the worst air quality index among major global cities on Wednesday and Ottawa issuing urgent air quality alerts. The fires have also forced the temporary suspension of Canadian National (CN) rail operations and triggered emergency evacuations across several communities.

Air Quality Crisis in Toronto and Ottawa

According to data released by Environment Canada, Toronto's Air Quality Health Index was classified as 'very high risk' — the most severe rating — placing the city at the bottom of global air quality rankings for the day. In Ottawa, the nation's capital, authorities issued air quality alerts as wildfire smoke combined with high humidity to trap particulate matter at ground level, turning the sky a striking yellow. Weather authorities warned the heavy smog is expected to persist for several more days, driven by prevailing airflow and wind patterns.

CN Train Surrounded by Flames Near Armstrong

A video that circulated widely on social media captured the scale of the danger on the ground: a CN train was shown engulfed by raging wildfires near Armstrong, Ontario, with towering flames consuming the woods on both sides of the tracks and casting an intense red glow inside the locomotive cab. The footage was filmed late Monday by a crew member aboard the train. CN confirmed the authenticity of the video on Wednesday, stating that the train crew had been safely evacuated. The railway has since announced a temporary suspension of operations along the affected section.

More Than 100 Active Fires Still Burning

As of Wednesday, more than 100 active fires remain burning across northwestern Ontario, according to reports. Emergency evacuations have been ordered for residents of several communities in the region. The scale of the blazes has overwhelmed local response capacity, with the fires spreading rapidly amid dry conditions and strong winds.

Canada's Accelerating Climate Crisis

This comes amid a documented and alarming trend: Canada is warming at a rate more than double the global average, with the Canadian Arctic experiencing temperature rises nearly three times the global rate. Over the past five years alone, the country has witnessed a sharp increase in severe weather events — from fatal droughts and devastating floods to increasingly destructive wildfire seasons. Scientists and climate experts caution that these events are not anomalies but accelerating patterns, and that conditions are expected to worsen in the years ahead. The 2023 wildfire season was already Canada's worst on record, and the current fires suggest 2025 is tracking a similarly destructive path.

What Comes Next

Authorities continue to monitor wind patterns that are spreading smoke eastward toward densely populated urban centres. Residents in affected areas have been advised to stay indoors, use air purifiers, and avoid strenuous outdoor activity. The duration of the rail suspension and the pace of evacuations will depend heavily on whether firefighting efforts can contain the most active blazes in the coming days.