At 9:13 a.m. on Wednesday, the National Weather Service reported an air quality alert in effect until Thursday at midnight for Morris, Hunterdon, Somerset, Middlesex and Mercer counties.

Milwaukee, Ozaukee, Racine, Kenosha and Sheboygan are all under a poor air quality alert from noon to 11 p.m., according to the National Weather Service. The air quality index is expected to reach the "unhealthy for sensitive groups" to even the generally "unhealthy" level throughout the afternoon and evening, NWS says.