Air Quality Alerts Issued for Parts of Texas on Memorial Day

The National Weather Service issued air quality alerts for the Dallas-Fort Worth region and the Houston, Galveston, and Brazoria areas on Monday. The alerts warned that atmospheric conditions are likely to support elevated levels of ozone, a harmful air pollutant.

Recommended actions include carpooling, walking or biking, bringing lunch from home, avoiding drive-through lanes, conserving energy, and ensuring vehicles are properly maintained.

Days have been issued for these areas.

The forecast seasons are based on periods when each region is most likely to see elevated ozone levels. Forecasters assess whether concentrations are expected to reach or exceed the EPA's AQI Level Orange threshold, defined as an eight-hour average of 71 parts per billion or a one-hour average of 125 parts per billion.

Meteorologists use historical weather patterns, ozone monitoring data, and predictive models to make these determinations. When an Ozone Action Day is issued, they coordinate with the National Weather Service, which then disseminates the alert.

Ground-level ozone is formed through chemical reactions between oxides of nitrogen and volatile organic compounds in the presence of sunlight. The EPA states that those most vulnerable to exposure include people with asthma, children, older adults, and individuals who spend time outdoors.

Depending on the level of exposure, ozone can cause coughing, a sore throat, and difficulty breathing deeply. It can also inflame airways, increase susceptibility to infection, worsen lung conditions such as asthma and emphysema, and raise the frequency of asthma attacks.