Denver, Colorado – Unhealthy ozone levels are expected to blanket the Colorado Front Range through 4 p.m. Monday, threatening residents in Denver, Fort Collins, Greeley, and surrounding counties with respiratory risks and reduced air quality.
According to the Colorado Department of Public Health and Environment, an Ozone Action Day Alert remains in effect from 4 p.m. Sunday until 4 p.m. Monday for Denver, Jefferson, Boulder, Larimer, Weld, Adams, Arapahoe, Douglas, and Broomfield counties. While scattered thunderstorms helped suppress ozone on Sunday, air quality could deteriorate on Monday—especially in northern cities.
Residents in the alert area are urged to limit driving gas and diesel vehicles, avoid strenuous outdoor activity, and stay indoors if sensitive to air pollution. Health officials warn that active children, adults, and anyone with lung disease, such as asthma, face higher risk of symptoms like coughing or breathing discomfort. Key highways—including I-25, US-36, and C-470—may see fewer commuters Monday as drivers heed warnings.
To help reduce ozone pollution, use public transit or carpool and delay mowing or refueling until after 4 p.m. Monday. Colorado continues to address ozone through local policies, but residents can help by making small changes during the alert.
The Ozone Action Day Alert is expected to expire Monday evening, but additional advisories may follow if pollution persists. For the latest air quality updates, visit the Colorado Air Pollution Control Division’s website.
