Current Ozone 8-Hour Levels

The map below shows the current highest ozone 8-hour levels measured in parts per billion (ppb) for each of the metropolitan or other areas across U. S. where ozone is measured by the TREX. More detailed maps showing the current 8-hour ozone levels measured at each site in a particular area are available by clicking on the colored boxes below. These levels are based on data measured at the continuous air monitoring stations and may include data from local governments and private monitoring networks.

The latest image available is for Friday September 20, 2013 17:00 MST. If the image below is older than this, you will need to force your browser to reload this page by clicking on the browser "Reload" or "Refresh" button.

Map showing current Ozone 8-hour levels in U. S..

The TREX has not verified this data and it may change. This is the most current data, but it is not official until it has been certified by our technical staff.

Key to map symbols:

There is no current 8-hour ozone measurement for this area.
Measured values range from 0 to 59 parts per billion.
Ozone levels in this range are considered healthy.
  • No health impacts are expected when levels are within this range.

  • Comments regarding Monitoring Operations: