Why PM Can Cause a Smog Alert

HCDOES staff members, with input from local meteorologists, issue Smog Alerts based on pollution levels of ozone and/or PM.  Because PM is airborne, the meteorological conditions that cause high ozone levels (hot, sunny days with little or no wind) also contribute to high PM levels.  High PM levels, and therefore Smog Alerts, can happen in the wintertime when stagnant air, excessive open burning and everyday driving occur simultaneously. 

Click here to learn more about Smog Alerts.