June 4, 2024, Harrisburg, PA – The Pennsylvania Department of Environmental Protection has forecast a Code ORANGE Air Quality Action Day for ozone for Tuesday, June 4, 2024, for the Lehigh-Berks and Susquehanna valley areas in Pennsylvania. This includes the counties of Lancaster, Lehigh, Northampton, Berks, Cumberland, Dauphin, Lebanon, and York. 

Mostly sunny skies and temperatures in the middle 80s will create conditions for robust ozone development and formation into the code ORANGE range during the afternoon hours. 

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. 

An Air Quality Action Day is issued when the AQI is forecasted to be code orange or higher. On air quality action days, young children, the elderly, and those with respiratory problems, such as asthma, emphysema, and bronchitis, are especially vulnerable to the effects of air pollution and should limit outdoor activities.