An ozone air quality health watch has been issued for Thursday because of high levels of ozone concentrations this week and expected higher-than-normal temperatures.
On Tuesday, ozone concentrations within the Arizona Department of Environmental Quality’s forecast area reached their highest levels since Sept. 20, 2011. Ozone is an invisible gas produced when other pollutants in the air — such as combustion — are heated by the sun. It can aggravate existing respiratory conditions like asthma.
Young people, as well as the elderly and those with respiratory issues should limit time outdoors Thursday. Peak ozone levels usually come in the early evening.