A haze of 'hazardous' proportions has descended upon the eastern United States, courtesy of wildfires raging across south-central Canada and Minnesota. As millions of residents struggle to breathe, over 20 states have been issued air quality alerts, with NASA tracking the smoke plumes from more than 180 active fires in northern Ontario as they spread south-east, affecting parts of Quebec and numerous US states.
The impact has been felt far and wide, from Detroit – currently ranked as having the world's worst air quality – to Toronto, Minneapolis, and Chicago. According to IQAir's rankings, these cities are among those bearing the brunt of the smoke-filled skies, with conditions deteriorating rapidly due to high temperatures and stagnant air.
Air quality alerts have been issued for a vast swathe of states, including North Carolina, Minnesota, Vermont, Connecticut, New York, Massachusetts, Rhode Island, New Jersey, New Hampshire, Pennsylvania, Illinois, Indiana, Ohio, Delaware, West Virginia, Colorado, Virginia, Maryland, Washington D.C., Michigan, and Wisconsin. In some areas, the US Environmental Protection Agency's map indicates 'unhealthy' air quality, escalating to 'very unhealthy' in parts of Illinois, Wisconsin, Michigan, and Ohio, while 'hazardous' conditions prevail in certain areas of Michigan and Minnesota.
In New York City, where high temperatures have prompted a heat emergency plan, authorities are urging residents to stay indoors, limit outdoor activity, and hydrate. Mayor Zohran Mamdani has opened numerous cooling centres, while Governor Kathy Hochul is distributing over 100,000 N95-style masks to affected counties and commuters.
As the National Weather Service in Detroit warns of dense smoke through Thursday afternoon and evening, officials are closely monitoring the situation, keenly aware that current conditions do not yet mirror those experienced during last year's significant smoke event. Boston forecasters predict smoky skies and reduced air quality throughout Thursday, with rain forecast for Saturday potentially offering some respite ahead of Sunday's World Cup Final in New Jersey.