Tracking air quality across the Chicago area

Air quality alerts were issued for at least 16 states Wednesday, as a dark yellow-gray-orange haze covered the sky across the northeast as smoke from over 400 Canadian wildfires drifted southward and enveloped cities like New York and Philadelphia.

While the same wildfires kept the Chicago area under air quality alerts over the weekend and into Monday, the air on the East Coast was so bad that it created hazardous conditions and stopped most outdoor activity. New York Mayor Eric Adams said the air quality index there hit 484 Wednesday; 50 is normal and anything over 300 makes for hazardous conditions.

Thick smoke is forecast for Philadelphia, Baltimore and Washington D.C. Wednesday night into Thursday, and the smoke is creeping toward Northwest Indiana and Chicago, which spells trouble for anyone local with respiratory issues.

The air quality index breaks down as follows:

• Green: value of -50 indicating Good air quality and air pollution poses little to no risk
• Yellow: value of 51 to 100 indicating Moderate air quality which is considered acceptable, but may pose a risk to some people, particularly those sensitive to air pollution
• Orange: value of 101 to 150, indicating Unhealthy for Sensitive Groups air quality, in which those in sensitive groups are likely to be affected but the general public is less so
• Red: value of 151 to 200 indicating Unhealthy air quality, in which some members of the general public could experience health effects and members of sensitive groups may experience more serious health effects
• Purple: value of 201 to 300 indicating Very Unhealthy air quality, in which the risk of health effects is increased for everyone and a health alert is issued
• Maroon: value of 301 and higher in which the everyone is more likely to affected by air quality and is considered a health warning of emergency conditions

You can also track the air quality in your zip code at the EPA's AirNow website.

Track the Chicago area's air quality below.