Texas Issues Ozone Action Day for Dallas-Fort Worth Area

State officials issued an Ozone Action Day for the Dallas-Fort Worth area on Sunday, May 24. The alert, distributed through the National Weather Service office in Fort Worth, warns that weather conditions favor elevated ground-level ozone, the main component of smog.

The advisory covers northern parts of Texas, with the highest concern centered on Dallas, Fort Worth, and Arlington. Officials said high traffic volumes and concentrated emissions in these cities increase the likelihood of ozone formation during peak afternoon and early evening hours.

Ground-level ozone forms when nitrogen oxides and volatile organic compounds from vehicles, power plants, refineries, and solvents react in sunlight. Hot, still weather traps the resulting pollution near the ground rather than allowing it to disperse.

The Environmental Protection Agency states that breathing elevated ozone can irritate lungs, trigger asthma attacks, and reduce lung function. Children, older adults, and people with existing lung conditions face the greatest risk of coughing, chest tightness, and worsening respiratory symptoms.

Ozone exposure can also slow plant growth and damage forests and crops. Officials recommend limiting outdoor activity during afternoon hours and avoiding strenuous exercise outside when levels are high.

To reduce emissions, residents are asked to carpool, walk, or bike instead of driving alone. Officials specifically urge drivers to avoid drive-thru lanes and vehicle idling, conserve electricity, and keep cars well-maintained. Texas ranks 46th among states for air quality according to 2026 data compiled by World Population Review.

Similar conditions affect Arizona, Nevada, New Mexico, Illinois, Utah, Colorado, California, and Oklahoma.