Authorities say the air on the Fourth of July will be unhealthy for some people.

The Indiana Department of Environmental Management has declared an Air Quality Action Day for Friday.

A high pressure system is expected to settle over the region, creating stagnant atmospheric conditions. Combining the hot temperatures, sunny skies, and light winds that are expected tomorrow as well as emissions in the air from fireworks are leading to an orange or unhealthy level warning from the agency. They say that there are expected to be high levels of fine particulates in the air making it hard to breathe for some.

That could be unhealthy for active children and adults and for those with respiratory diseases, such as asthma. If you are at risk, you should limit prolonged exposure outdoors tomorrow.

The warning is in effect from midnight tonight to midnight Friday.

You can get more information here: http://www.in.gov/idem/airmonitoring/smogwatch/