As of Sunday, July 19, 2026, communities across the United States continue to experience significant impacts from widespread Canadian wildfires. Persistent smoke plumes have drifted south, causing a dramatic decline in US air quality and prompting health advisories for millions of residents. This ongoing environmental challenge highlights the far-reaching effects of climate events and the critical importance of monitoring local conditions for public safety.
Our chart, "Daily Average Air Quality Index (AQI) in US Cities (July 15-19, 2026)," illustrates the estimated daily average Air Quality Index for New York City, Washington D.C., and Chicago over the past five days. Key takeaways reveal that Chicago faced particularly hazardous air quality on July 16, with AQI levels exceeding 300. New York City and Washington D.C. also contended with 'unhealthy' to 'very unhealthy' air quality during this period, underscoring the broad geographical reach of the wildfire smoke.
Due to the rapidly evolving nature of these events, specific daily average AQI values were not consistently available in real-time. Therefore, the data points presented are approximated, based on reported air quality alerts and specific high readings for each city during the July 15-19 timeframe. This chart provides a timely, estimated overview of the air quality challenges faced by these major US cities.