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 19 to 400 PM Thursday August 20
IMPACTS...Ozone Action Day Alert is now in effect for the Front Range Urban Corridor. Ozone concentrations in the Moderate to Unhealthy for Sensitive Groups range are expected on Wednesday and Thursday. The highest ozone levels are most likely in the southern and western portions of 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. Thursday, August 20, 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.