Northwest Indiana Faces Elevated Ozone Levels and Air Quality Concerns
As summer begins, air quality alerts are expected to increase in Northwest Indiana, particularly for elevated ozone levels. According to Mark Derf, a meteorologist with the Indiana Department of Environmental Management (IDEM), ozone alerts typically occur in spring, summer, and early fall due to stagnant air, warmer temperatures, and lower humidity. In 2025, IDEM declared four Air Quality Action Days for ozone, while 2024 saw eight such days for fine particulate matter, which can occur year-round. Last year, Canadian wildfire smoke exacerbated air quality issues, combining with stagnant conditions to worsen pollution. Valparaiso University researchers have also observed unusual ozone spikes between midnight and 2 a.m., potentially linked to pollution transport from Chicago. The findings highlight the ongoing challenges of managing air quality in the region. 
