The U.S. National Weather Service extended air quality alerts for another day for the East Coast from New England to South Carolina, as well as parts of the Midwest, including Ohio, Indiana and Michigan. The U.S. Air Quality Index (AQI) measures five major pollutants, including particulate matter produced by fires. While the faint smell of burning wood lingered, the smothering blanket of yellow and orange-tinged haze appeared to thin out, bringing a modicum of relief. "We urge residents and visitors to follow precautions related to the 'Code Purple' air quality alert." Large swaths of Michigan are also under red flag warnings due to dangerous fire weather conditions in both of the state's peninsulas, according to the weather agency.

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