Chicago's Air Quality Hits AQI 342 as Wildfire Smoke Blankets the Midwest

It is another day of dangerous air quality conditions for millions of Americans living in the Upper Midwest, the Great Lakes, and the Northeast. What parts of the U.S. are seeing the worst air on Friday? Here is what you need to know.

Dangerous Air Quality Conditions Across Several Major U.S. Cities

The zone from Chicago to Pittsburgh has been dealing with the most hazardous air conditions as the work week comes to a close. Thick smoke generated from wildfires burning in Ontario, Canada, is the culprit behind the unhealthy air.

There are over 800 wildfires raging across Canada, sending the smoke billowing to the south and into the U.S. The scene across many American cities is reminiscent of the historic outbreak of Canadian wildfires from three summers ago.

Air quality alerts are now in place for all of Wisconsin, Delaware, Pennsylvania, Michigan, New Jersey, Ohio, and Maryland. A number of America's largest cities have been caught up in the smoke, impacting millions of people. For instance, Chicago woke up to some of the worst air quality index (AQI) readings in the world, coming in with a measurement of 342.

The smoke and haze are traveling as far south as Washington, D.C. The nation's capital saw an AQI of over 250 on Friday morning. Any reading over 250 is considered to be in the "dangerous" zone. Other urban areas with AQI readings of over 250 on Friday included Pittsburgh, Cleveland, and Detroit.

According to physicians, an AQI reading of over 150 for a full day is the equivalent of smoking 7 to 9 cigarettes. As such, it is easy to see how exposure to this degree of smoke can trigger serious health impacts, including throat irritation, itchy eyes, headache, and difficulty breathing.

The smoke and haze began to move across the northern U.S. on Wednesday, becoming more entrenched over the region on Thursday. Tourists to Niagara Falls were greeted with an orange-gray shroud of smoke over the famous waterfalls. While the air quality improved a bit on Friday, the popular summer vacation destination is still dealing with unhealthy conditions.

The only good news to come out of this weather pattern is that the smoke is turning down the high temperatures within a stubborn heat dome.

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