Historical Data

Ozone Exceedance Summary

The Excel file named Ozone Exceedance Summary in the listing below contains the Ozone Exceedance Summary for the each ozone season for the last 10 years. Ozone season officially runs from April 1st through September 30th. Since exceedances have occurred in March, every effort is made to bring the monitors back up as soon as practical each year.

The Ozone Exceedance Summary includes the date and monitor name(s) with the highest 8-hour average for the day when an 8-hour ozone average exceeded the 2015 National Ambient Air Quality Standard for Ozone which is 0.070 parts per million (70 parts per billion).

The cells containing the maximum 8-hr ozone average for each site have background colors associated with the appropriate category of the Air Quality Index as revised in 2015.

QA Analyzed Data

The quality assured (QA'd) data for Ozone and Particle Pollution for the last 10 years is contained in the appropriate file below.

Ozone data is the maximum 8-hour average for the day at each site.

Particle pollution data is the midnight to midnight 24-hour average for each day. Please read the material on the first worksheet in the file for important information to keep in mind when viewing the data.

Preliminary Data

The preliminary data provides both ozone and particle pollution data for the year that has not yet been QA’d.