Agronomy Hall at Iowa State University hosts a PurpleAir air quality sensor. Unfortunately, wild fires and the associated smoke continues to be a problem plaguing much of the country. The featured chart presents the daily range of PM2.5 (2.5 micrometers or less) Air Quality Index (AQI) for 2026. The chart colors represent the ranges of values associated with the given AQI rating. The wild fire smoke has certainly been noticeable over Iowa these past number of weeks. The hazardous levels were reached just over a week ago on 24 July.