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Air Quality Alert


COC035-031-013-069-005-123-059-001-014-212200-
Douglas-Denver-Boulder-Larimer-Arapahoe-Weld-Jefferson-
Adams-Broomfield-
410 PM MDT Thu Aug 20 2026

...OZONE ACTION DAY ALERT FROM 400 PM THURSDAY UNTIL 400 PM
FRIDAY...

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 Thursday August 20 to 400 PM Friday August 21

IMPACTS...Ozone Action Day Alert is now in effect for the Front
Range Urban Corridor.  Hot, sunny, and stagnant weather will allow
ozone to reach the Unhealthy for Sensitive Groups concentration on
Thursday and Friday. The highest concentrations are expected in
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.
Friday, August 21, 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.

$$

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Page last modified: June 2, 2009
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