New Yorkers warned to stay indoors as Manhattan's air quality rates among world's worst

The air quality in New York City was considered among the world's worst today, along with poor air conditions in Detroit, Washington D.C., and Delhi, India. (See astonishing live Web cam images at New York Metro Weather.)

And until the city's unhealthy air, polluted by Canada's wildfire smoke, clears up, Mayor Eric Adams warns "vulnerable New Yorkers to stay inside" and all New Yorkers to "limit outdoor activity to the greatest extent possible."

"Stay inside, close windows and doors, and use air purifiers if you have them," the mayor said in a statement released last night, emphasizing that people who are older or who have "heart or breathing problems" should "remain inside."

"If you must go outdoors, wear a high quality mask such as a KN95," he said, adding, "We recommend all New Yorkers take the precautions that they see fit to protect their health."

Adams said that although air quality is expected to slightly improve tonight and tomorrow morning, it is "expected to further deteriorate tomorrow afternoon and evening." (See video below, posted by The Recount.)

From CBS News:

Particulate matter in New York's air was measured at 14.5 times the World Health Organization's annual air quality guideline value, IQAir said, but it's expected that it will improve to at least "moderate" through the weekend. 

This is a stark difference from the typical air in New York City, which IQAir says has had an AQI of less than 50, classified as "good," in recent years. 

Although it had not yet been formally listed on the IQAir world's-worst air quality list for unknown reasons, Washington, D.C., according to the company, has an AQI of 180 – 22.3 times the WHO's recommendation – which would place it just behind Delhi. According to the government-run website AirNow, the air quality in the nation's capital is even higher, with an AQI of 194.