From the article:

Smoke from wildfires raging across northern Minnesota and western Ontario in Canada is forecast to drift into the lower levels of the atmosphere across the Midwest, Northeast and Mid-Atlantic from Wednesday to Friday, probably creating unhealthy air quality conditions.

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This smoke was billowing from a dozen large and out-of-control wildfires burning in western Ontario.

The largest one had grown to more than 130,000 acres late Tuesday.

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Meanwhile, several large wildfires in Minnesota were also contributing to the smoke plumes. The two largest fires there were called the Thumb Fire and the Bear Trap Fire, burning through 14,500 and 13,500 acres, respectively.

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“At this time, current forecasts do not indicate a repeat of 2023 conditions,” wrote New York City Emergency Management in a statement on Tuesday, while adding that the arrival of the smoke would coincide with high heat on Wednesday, creating simultaneous “environmental health challenges.”

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This time, the highest and most dangerous smoke concentrations may end up occurring in eastern Minnesota, northern Wisconsin, Michigan and western New York, which are closer to the fires.