An official website of the United States government.

We've made some changes to If the information you are looking for is not here, you may be able to find it on the EPA Web Archive or the January 19, 2017 Web Snapshot.

Outdoor Air Quality Data

Air Data - Ozone Exceedances

How does this year compare with previous years? Compare 8-hour ozone exceedances between two years or multi-year periods for a city or county. The first plot shows the comparisons by MONTH. The second plot shows the comparisons by DAY based on cumulative counts. The third plot shows the comparisons by YEAR.

  1.     -- or --
  2. To:
  3. To:


Top of Page