Some of the worst air in the world right now is in your backyard.

The Wisconsin Department of Natural Resources has issued an Air Quality Alert for the entire state of Wisconsin through noon on Thursday. The cause of the air quality alert continues to be the Canadian wildfires that have been raging for weeks. According to the National Weather Service, the eastern half of the state will experience the heaviest surface smoke from noon on Tuesday to noon on Wednesday, causing the air quality index (AQI) to reach unhealthy and very unhealthy categories with the possibility of reaching hazardous levels. By comparison, the air quality advisory over the weekend only reached “unhealthy for sensitive groups.” It is recommended that people with heart or lung disease, older adults, and children should avoid prolonged or heavy exertion and consider avoiding all physical outdoor activities.

The Milwaukee Journal-Sentinel reported that several cities in Wisconsin, Michigan, and Minnesota have AQI readings worse than some of the biggest cities in the world including Dubai (UAE), Doha (Qatar), Delhi (India), and Beijing (China).  As of 7 a.m., Chicago had the worst AQI among the world’s major cities at 164. Green Bay, by comparison, was at 163 as of Monday night.