MILWAUKEE -- The Wisconsin Department of Resources says a Minnesota forest fire is causing southeastern Wisconsin air to be unhealthy for everyone.
Officials raised the air quality index to red on Wednesday for Waukesha, Milwaukee, Racine and Kenosha counties until 11 p.m. because of persistent elevated levels of fine particles in the air.
DNR spokeswoman Bill Cosh says the red index is rare.
Those fine particles are from the fire that has scorched at least 160 square miles, and threatens residents of the town of Isabella.
Federal guidelines require the air quality to be at a certain level for 24 hours before the official level is changed. Cosh says the weather conditions are improving.
An air quality index of orange was set for Dodge County, meaning the quality is unhealthy for sensitive groups.
A lightning strike ignited the northeastern Minnesota blaze August 18 and its smoke has drifted to the Milwaukee and Chicago areas.
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