Several large wildfires burning in Canada and in the US state of Minnesota are producing heavy smoke that is expected to spread across much of the Midwest and parts of the Northeast in the coming days. ABC News reports that more than 800 wildfires are burning in Canada, contributing to widespread smoke alerts. The Independent says the combination of major fires in Canada and Minnesota is forecast to expose millions of people to dangerous air pollution this week, as the smoke plume moves toward the US. The articles describe smoke warnings rather than direct fire impacts, indicating that the main near-term concern for many Americans is deteriorating air quality. Health and environment authorities in the affected regions issue advisories to prepare for periods of unhealthy conditions. While the specific locations may vary by forecast and day, all accounts describe a broad, cross-border smoke event driven by active fire activity in Canada and Minnesota and anticipated impacts on large parts of the US Midwest and East.