OZONE ACTION DAY ALERT FROM 400 PM WEDNESDAY UNTIL 400 PM THURSDAY... 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 Wednesday August 26 to 400 PM Thursday August 27 IMPACTS...Ozone Action Day Alert is now in effect for the Front Range Urban Corridor. Ozone concentrations in the Unhealthy for Sensitive Groups category are possible both Wednesday and Thursday during the afternoon and evening hours. The best chance for these elevated ozone levels will be in western parts of the Denver metro area, including the adjacent foothills. 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. Thursday, August 27, 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 during the afternoons and evenings both Wednesday and Thursday.