The Omaha area's ozone levels rose high enough Monday afternoon to prompt the Douglas County Health Department to issue its first air-quality alert of the season.

An alert means that concentrations of air pollution in the region may be unhealthy for people with asthma or other lung or heart problems, plus the elderly, very young children and pregnant women. The alert was to expire Monday evening, said Russ Hadan, an air-quality specialist with the department.

Abundant sunshine, high temperatures and very low winds allow the ozone to build up, Hadan said.

The forecast for Tuesoday, he said, called for winds strong enough to help keep ozone levels lower than Monday's, but levels still may be close to the "unhealthy for sensitive groups" range.

County officials recommended that, during air-quality alerts, people contact their health care providers if their symptoms worsen, they begin coughing repeatedly, or they experience shortness of breath, difficulty breathing, wheezing, tightness, pain in the chest, abnormal heartbeat, nausea, unusual fatigue or a lightheaded feeling.