Decatur, Ill. (WCIA) – Air quality continues to worsen into Wednesday afternoon, with the Air Quality Index now listed as “Hazardous” for parts of Central Illinois.

The latest data at 12:00 p.m. Central Time shows that Decatur has breached into the “Hazardous” air quality category. This is the worst quality air possible on the scale.

The Air Quality Index uses a color scale with words ranking from Good to Hazardous based on the level of particulate matter and the amount of ozone in the atmosphere.

GreenGood0 to 50Air quality is satisfactory, and air pollution poses little or no risk.
YellowModerate51 to 100Air quality is acceptable. However, there may be a risk for some people, particularly those who are unusually sensitive to air pollution.
OrangeUnhealthy for sensitive groups101 to 150Members of sensitive groups may experience health effects. The general public is less likely to be affected.
RedUnhealthy151 to 200Some members of the general public may experience health effects; members of sensitive groups may experience more serious health effects.
PurpleVery Unhealthy201 to 300Health alert: The risk of health effects is increased for everyone.
MaroonHazardous301 and upHealth warning of emergency conditions: everyone is more likely to be affected.

The Hazardous ranking assigned to Decatur Wednesday at Midday was the second worst air quality in the world, and worse than all of the major cities reporting. Only the Akron, OH reported worse air quality.

Air quality like we are experiencing is going to cause health issues potentially for a large portion of the population. Doctors are concerned about the respiratory issues that can flare up from such dangerous air in place.

The smoke and haze has been brought our way thanks to out-of-control wildfires in Canada and a favorable jet stream with a low and a high on opposite ends, forcing smoke overhead and shoving it down to the surface.

It is expected that air quality will eventually start to improve heading into Wednesday Night and Thursday morning, though that brings a risk for severe weather with it. Read more about that here.