Cherry Creek State Park

Air Quality Alert issued July 21 at 4:10PM MDT by NWS Denver CO

The Colorado Department of Public Health and Environment has issued the following... WHAT...Ozone Action Day Alert. WHERE...Douglas, Jefferson, Denver, western Arapahoe, western Adams, Broomfield, Boulder, Larimer, and Weld Counties WHEN...400 PM Tuesday July 21 to 400 PM Wednesday July 22 IMPACTS...Ozone Action Day Alert is now in effect for the Front Range Urban Corridor. Hot and sunny weather with limited chances for afternoon storms will allow ozone concentrations to reach the Unhealthy for Sensitive Groups category on Tuesday and Wednesday. On Tuesday elevated ozone is possible in the Denver Metro area, Fort Collins, Greeley, and surrounding areas. On Wednesday the highest ozone is expected to be confined to locations within the Denver Metro area. For Colorado air quality conditions, forecasts, and advisories, visit: https://www.colorado.gov/airquality/colorado_summary.aspx If possible, please help us reduce ozone pollution by limiting driving gas and diesel-powered vehicles until at least 4 p.m. Wednesday, July 22, 2026. Colorado is also addressing ozone pollution through state policies. For more information about health impacts and how ozone pollution forms in Colorado, visit: https://cdphe.colorado.gov/ozone- pollution-and-your-health HEALTH INFORMATION...Increasing likelihood of respiratory symptoms and breathing discomfort in active children and adults and people with lung disease, such as asthma. Active children and adults, and people with lung disease, such as asthma, should reduce prolonged or heavy outdoor exertion.