Smoke From Hundreds of Canadian Wildfires Triggers Air Quality Alerts Across US

Smoke from hundreds of wildfires burning across Canada has spread into the United States, prompting widespread air quality alerts across several northern states as officials warn residents to limit outdoor activity.

According to the Canadian Wildland Fire Information System, 858 wildfires are currently active across the country, including 30 new blazes reported on Thursday. Most of the fires remain out of control.

The largest concentration of fires is in northwestern Ontario, where thick smoke has blanketed communities including Thunder Bay and Toronto. Higher-altitude smoke has also drifted across the Great Lakes and into parts of New York, creating hazy skies and producing unusually red sunrises and sunsets.

The smoke has pushed air quality to hazardous levels across parts of Michigan and Minnesota, with the US Air Quality Index advising residents to stay indoors where possible. Air quality alerts also extend across the Upper Midwest, the Great Lakes region and into the northeastern United States.

In western New York, air quality has reached “very unhealthy” levels, while conditions across the New York City metropolitan area have been classified as “unhealthy.” On Wednesday, city officials expanded heat emergency measures and activated air quality emergency protocols, opening hundreds of cooling centres and distributing KN95 masks to residents.

Forecasters say thunderstorms are expected across parts of Ontario over the coming days, although the rainfall is unlikely to significantly slow the spread of the fires.

Northwesterly winds are forecast to continue carrying wildfire smoke into the northern United States through the weekend, raising concerns that haze could reach New Jersey ahead of Sunday’s World Cup final.

Meteorologists expect a shift in wind direction by Monday, which should redirect much of the smoke toward Quebec and gradually improve air quality across the northeastern United States.