The Ozone Alert! Season for the Tulsa area is May through September each year. During these months, hot still weather conditions and the sunlight “cook” ground-level emissions in a way that ozone pollution is formed. Ground level ozone can reach levels determined to be unsafe by the EPA. The Oklahoma Department of Environmental Quality (ODEQ) maintains five ozone monitoring stations in the Tulsa area, as indicated on the map below. The measurements from these stations are used by EPA to determine if the Tulsa area meets the ozone standard established by the federal Clean Air Act.