Code Orange air quality warning issued for Tuesday

Youth, older population and those with heart and/or respiratory conditions cautioned


DOVER — Tuesday will be an Ozone Code Orange Air Quality Action Day in the First State, according to a warning issued Monday by the Delaware Department of Natural Resources and Environmental Control.

Such warnings are issued when levels of pollution can be unhealthy for sensitive groups, such as young children, older adults and those with heart and/or respiratory conditions.

Those individuals should limit outdoor activities, especially those that require a high level of exertion.

“Upper-level high pressure west of the state will inhibit low-level mixing. In addition, mostly sunny skies and temperatures in the mid-90s will enhance ozone production. Furthermore, calm to light northerly winds will reduce dispersion, allowing pollutants to accumulate. Therefore, (air quality index) levels are anticipated to be Unhealthy for Sensitive Groups for ozone and low-Moderate for (Particulate Matter)2.5,” the department stated in a Monday news release. Fine particulate matter is defined as particles that are 2.5 microns or less in diameter.

Extended forecast

On Wednesday, northwesterly winds will strengthen slightly, aiding dispersion. However, abundant sunshine and temperatures in the mid-90s will continue to promote ozone production. Therefore, AQI levels are anticipated to be high-moderate for ozone and low-moderate for PM2.5.

Low-level mixing will increase Thursday, as an upper-level trough of low pressure approaches Delaware. However, southerly to southwesterly winds will transport regional pollutants into the state, and temperatures in the mid-90s will support ozone development. Thus, the air quality index levels are forecast to be mid-moderate for ozone and high-good for PM2.5.

Any health-related questions should be directed to the Division of Public Health at 302-744-4700. Other questions can be asked of the Division of Air Quality at 302-739-9402.

For information about the air quality alerts and steps to reduce air pollution, visit

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