Monsoon rains have helped bring down ozone levels along the Front Range after last year's record levels.
The rain has meant a summer of healthier air for Denver residents, and may help the metro region meet tough federal standards for ozone.
The lower levels are evident in air pollution data from monitors
spread from Colorado Springs to Rocky Mountain National Park.
Thirteen of the 14 regional monitors showed declines in maximum
ozone concentrations. None have exceeded federal standards.