Environment Canada is warning of poor air quality and forecasts that air pollution levels could pose a health risk for residents in the Hamilton area on Sunday due to an ongoing heat wave.

In a special air quality statement, the federal weather agency warns that "possible high levels of air pollution are expected today" because of hot and sunny conditions.

The unseasonably warm weather is expected to cause increasing ground-level ozone concentrations this afternoon, the statement read.

Environment Canada says moderate air quality values are also expected during the day, with the "potential of short term high-risk" values in the afternoon.

People may experience symptoms, such as increased coughing, throat irritation, headaches or shortness of breath.

Children, seniors and those with cardiovascular or lung disease, such as asthma, are especially at risk, the agency says.

Environment Canada is advising people who are experiencing symptoms, such as coughing or throat irritation, to consider reducing or rescheduling strenuous outdoor activities until the special air quality statement is lifted.