The Pennsylvania Department of Environmental Protection (DEP) has issued a Code Orange Air Quality Action Day for ozone for Sunday, July 19th for Montgomery, Chester, Delaware, Montgomery, and Philadelphia counties.

The Code Orange is due to the DEP’s Sunday forecast of “sunshine for most of the day, with light southwest winds, high temperatures expected in the mid to upper-90’s. These conditions will create rapid and robust ozone formation within the Air Quality Action Day area.”

The U.S. Environmental Protection Agency’s Air Quality Index (AQI) provides standardized color codes for forecasting and reporting daily air quality. Green signifies good air quality; yellow means moderate air quality; orange represents unhealthy pollution levels for sensitive groups of people; and red warns of unhealthy pollution levels for all.