Ozone levels may rise to unhealthy heights Tuesday and Wednesday, prompting ozone health watch alerts for both days.
The health watch is an extension of one issued Monday, when ozone levels were expected to approach federal standards. A health advisory is issued when levels are expected to exceed federal standards. The Arizona Department of Environmental Quality issued a health advisory over the weekend.
Ozone is an invisible gas that is created when pollutants in the air are heated by the sun. Temperatures Tuesday are expected to rise above 100.
Adults and children with respiratory conditions should limit time outdoors, especially in the afternoon when ozone creation is at its peak.






