National Weather Service issues air quality alerts for 16 states as Canadian wildfire smoke drifts south

The National Weather Service issued air quality alerts early Saturday morning for portions of Minnesota, Michigan, Indiana, Ohio, West Virginia, Virginia, Maryland, Delaware, New Jersey, New York, Connecticut, Rhode Island, Massachusetts, Vermont, New Hampshire and Maine.

Smoke from roughly 820 Canadian wildfires, 156 of them out of control, continued to cross the border. The agency said the plume would affect New York City through the afternoon and that upstream areas in the Midwest would likely face poor air quality at least through Sunday.

Officials advised residents in areas with extreme warnings to limit outdoor activity. In zones rated very unhealthy or hazardous, people were told to stay indoors with windows closed. Doctors recommended that anyone with heart or lung disease remain inside.

Health officials suggested N95 masks for those who must work outdoors, noting the masks can filter at least 95 percent of airborne particles. President Donald Trump said Friday he would increase tariffs against Canada, accusing the country of not properly maintaining its forests and brush.

Four Republican House members from Michigan sent a letter this week stating Canada has the tools to prevent the smoke and has chosen not to.

Sen. Bernie Moreno said he will introduce a bill next week to sanction Canada and responsible Canadian government officials. Six Flags Great America in Illinois shut on July 17. Cedar Point in Sandusky, Ohio, ended operations early the previous day.

Dutch Wonderland in Pennsylvania also closed July 17. Detroit recorded the worst air quality of any major city on Earth on July 16, with 24-hour exposure equivalent to smoking about 21 cigarettes. Chicago, Minneapolis and Toronto also posted unsafe levels.

Canada had more than 700 active wildfires that had burned 8.2 million acres as of July 17. The same letter from the Michigan lawmakers noted this was the third consecutive year the group had written about the issue.