Wildfire Smoke Makes Air Dangerous for Millions in the Midwest and East Coast

Thick smoke from wildfires burning in Canada drifted south into the Midwest and northeastern United States on Thursday, making the air dangerous for millions of people. City skylines disappeared behind a hazy orange fog, and parks and beaches grew quiet as people stayed inside. Air quality reached some of the worst levels ever recorded in cities like Chicago, Detroit, and Cleveland, and conditions were still unhealthy in New York and Philadelphia.

The smoke came from about 800 wildfires burning across Canada, with roughly 180 of them in the province of Ontario. Those fires forced road closures and made some people flee their homes. Ontario's premier, Doug Ford, said more than 150 crews and nearly 50 firefighting aircraft were working around the clock to put the fires out.

A weather system called a heat dome helped spread the smoke deep into the U.S. A heat dome is a pocket of high-pressure air that traps heat — and in this case, smoke — close to the ground. Forecasters said a new weather system would push the smoke away from the Northeast by the weekend, but that parts of the Midwest might stay smoky longer.

The Air Quality Index, or A.Q.I., is a scale used to measure how clean or polluted the air is. An A.Q.I. below 50 is 'good,' while anything above 150 is 'unhealthy,' and above 300 is 'hazardous.' On Thursday, the A.Q.I. hit 785 in parts of Michigan and 775 in Toledo, Ohio — numbers far above the danger zone.

In Milwaukee, where the A.Q.I. reached 460, a man named Dave Sell visited Bradford Beach on Lake Michigan and found it nearly empty. Normally, thousands of people crowd the beach on a summer day, but only about 15 were there. 'You can't even see the blue water,' he said. 'It looks dingy and gray and brown, and the smell is gross.'

Wildfire smoke can be harmful to many people's health. It can make breathing problems like asthma much worse, and it raises health risks for people with conditions like diabetes or heart disease. Children, pregnant women, and even healthy people can feel the effects, including coughing, watery eyes, headaches, and chest pain.

City and state leaders urged people to stay indoors as much as possible. New York Governor Kathy Hochul said the state would hand out more than 100,000 masks at places like Penn Station and Grand Central Terminal. New York City also made free masks available at some public libraries, and Chicago closed its beaches and outdoor pools for the day.

Some people had no choice but to go outside. Brandon Olsen took his dog Juni for a short walk in Chicago but planned to skip their evening walk. 'I walked outside and could feel it in my eyes,' he said. 'It has a metallic taste and probably isn't too good of an idea to be out here long.' In New York, a father named Robert Vargas said he was worried the smoke could harm his 9-year-old son's lungs.

The smoky skies also stirred up political tension between the United States and Canada. Four Republican members of Congress from Michigan sent a letter to Canadian Prime Minister Mark Carney, accusing Canada of not doing enough to manage the fires. When Carney was asked about the criticism, he said, 'There must be a contribution from the United States in the fight against climate change.'

For some people in American cities, the smoky air was a reminder of what life is like in other parts of the world. Raj Advani, a software engineer walking his dog in New York City, said: 'This is how it is in Delhi every day.' Scientists warn that without action on climate change, smoky summer days could become the new normal for many more Americans.