Last week, Canadian wildfire smoke blanketed Wisconsin and caused the Air Quality Index to reach the unhealthy level for sensitive groups. Six days later, on July 31, the smoke appears to have a worse impact on the air.

Wisconsin currently has the most unhealthy air in the country. The Wisconsin DNR reports widespread Unhealthy (Red) AQI for PM2.5 is expected across the state Thursday, with NowCast AQI values in the Very Unhealthy (Purple) category possible.