Smoke from Canadian wildfires was enveloping the region Thursday, creating a haze, a faint smell of charcoal, and a potential danger for people with respiratory issues.
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Air quality alerts were issued across the region. By daybreak, air quality was tumbling to unhealthy levels in Philadelphia and a broad swath of Pennsylvania and New Jersey, according to an Inquirer analysis of dozens of public sensors.
Massive fires are burning across Canada, and forecasters said wind patterns shifted this week to allow the smoke from those fires to enter the Northeastern and Mid-Atlantic United States.
Early Thursday morning, the amount of fine particulate matter in the air, measured by the Environmental Protection Agency in a metric called the Air Quality Index, or AQI, had risen sharply.
Air with an AQI above 150 is considered unhealthy to breathe with prolonged exposure for children, older people, and those with respiratory issues, according to the EPA. In air quality alerts issued by the National Weather Service, forecasters recommended avoiding prolonged outdoor exposure, particularly activities like exercise.
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The heat won’t help. Temperatures are expected to reach the upper 90s in Philadelphia Thursday, and it may feel like 100 degrees or more. A heat advisory is in effect for the Philadelphia metro region. Air quality tends to worsen in dense, urban environments during hot weather.
It was unclear when the smoke would dissipate across the region, but the National Weather Service said it could linger into Friday.
Forecasters urged residents across the eastern United States, particularly those with respiratory issues, to monitor alerts from local officials and be mindful of conditions where they live or work.
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