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Outdoor Air Quality Data

Air Data - Ozone Exceedances

Monday, August 20: AirData services are unavailable today due to a problem with the weekly database update. We expect services to be restored by Tuesday, August 21.

The interactive map and pre-generated files are still available during this outage.

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.

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