The sun shone feebly through the thick haze. The smell of burning wood hung thick in the air. Many New Yorkers donned masks as the air quality plummeted amid health warnings.The National Weather Service issued an air-quality alert because pollution levels were elevated as smoke from raging Canadian wildfires drifted south across a huge swathe of the US, reaching all the way to New York City and even beyond out into the Atlantic.Zohran Mamdani, New York City’s mayor, urged residents to stay inside. “Every New Yorker should take precautions. Limit your time outdoors, especially strenuous activity,” Mamdani said.Mamdani pointed out that the city had made free KN95 masks available at hundreds of locations citywide, including libraries, police stations and its famous firehouses.National Guard soldiers hand out face masks to commuters at Grand Central Terminal as haze from Canadian wildfires blankets Manhattan in New York City. Photograph: Spencer Platt/Getty ImagesOn Thursday evening, the city’s office of emergency management encouraged New Yorkers to avoid being outside for more than an hour. “Listen to your body,” the department posted on its X social media account. “If you have watery eyes, a scratchy throat, or difficulty breathing, reduce physical activity and go indoors.”John, a 31-year-old lifelong Queens resident with asthma, wore a mask outside so he could work security for a theater company at Times Square. His employer was encouraging staff to not overexert themselves and to take breaks in the theater for some fresh air, “but at the end of the day, we still got to be outside”, he said.“You can taste the burnt paper in the air,” said John, who only wanted his first name used.Beside John, a group of women were selling Broadway tickets.“These guys handing out Playbills and stuff on the sidewalk – they are out here all day with no protections,” he said. “The march of capitalism keeps moving forward.”A policewoman directs traffic as air quality in New York City reached one of its worst levels in three years. Photograph: Deccio Serrano/NurPhoto/ShutterstockThe smoky air was compounded by soaring temperatures. The heat in the city reached above 90F (32.2C) and in other parts of the US, a “heat dome” helped trap the stifling smoky air. In Detroit, closer to the burning Canadian forests, the Motor City registered the worst air quality in the world.Rachel Smalter Hall, an editor at a New York book publisher, received a message from her therapist Thursday morning to discuss whether they should keep their in-person appointment despite the hazardous air. Smalter Hall has asthma and said that if she doesn’t take care of it, she can “get bronchitis really easily”.They decided to meet remotely.“I had noticed when I was outside that my eyes were stinging,” said Smalter Hall, a mother of two who lives in downtown Manhattan.Wearing a face mask, Smalter Hall and her young daughter ventured to the Sephora store at the World Trade Center to try on makeup. She was worried about her kids.“The color of the sky changing” due to pollution “is becoming a more and more common thing, and it just makes me really concerned for the future of air quality, for the future of their health, for the future of the health of our planet,” she said.Wildfire smoke against the Manhattan skyline. Photograph: Christopher Neundorf/EPAIn Brooklyn, Jackie Bell was on maternity leave with a two-month-old girl and had planned to send her three-year-old boy to a camp at Prospect Park, but her husband needed their car.So attending camp would have meant Bell, 35, had to make 30-minute walks through the smoggy air in each direction from her home with her kids in tow. She opted to keep her children home. Bell’s mother drove from New Jersey to help “so I didn’t have a stir-crazy toddler at home”.“I’m just very grateful. I feel very privileged knowing that some people, despite the situation, might have to go outside,” said Bell, who works in healthcare.Aaron Freedman, a graduate student studying American history, still owned an N95 mask from the Covid-19 pandemic and wore it while walking to meet his mom for lunch in Brooklyn.He had seen people with masks the night before, and it “smelled so intensely of wildfire” that he decided he should wear one too.The smoke reminded Freedman, a lifelong New Yorker, of California, which often experiences wildfires. The only time he recalled a similar situation locally was in June 2023, when another Canadian wildfire caused New York’s air to become toxic and its sky to become orange.“Growing up, this never happened,” said Freedman, 34. “So yeah, climate change, it sucks.”