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Air Quality Alert Message

Status

Issued Active alert

Start Time

Wed 08/20/2025 09:10 PM EDT

End Time

Thu 08/21/2025 06:00 PM EDT

Impacts

Informational

Full Alert Message

Air Quality Alert Message Colorado Department of Public Health and Environment Relayed by National Weather Service Boulder CO 710 PM MDT Wed Aug 20 2025 ...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 20 to 400 PM Thursday August 21 IMPACTS...Ozone Action Day Alert is now in effect for the Front Range Urban Corridor. Hot, stagnant weather will allow ozone to reach the Unhealthy for Sensitive Groups category on Wednesday and Thursday. 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 21, 2025. 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.

Technical Header

COC031-014-069-123-035-059-005-001-013-212200- Denver-Broomfield-Larimer-Weld-Douglas-Jefferson-Arapahoe- Adams-Boulder- 710 PM MDT Wed Aug 20 2025