2025 Ozone Exceedances
(Through May 12, 2025)
Below are the exceedances of the 0.070 parts per million (ppm) eight-hour average ozone standard, and the dates they occurred for each ozone monitor in New England. These data are preliminary, not quality assured and are subject to change.
On this page:
Connecticut
| Monitor Location | Date/AQI Map | Concentration (ppm) |
|---|---|---|
| Middletown | May 12, 2025 Peak Ozone AQI Map | 0.071 |
| Cornwall | April 25, 2025 Peak Ozone AQI Map | 0.072 |
| Cornwall | April 24, 2025 Peak Ozone AQI Map | 0.076 |
| Danbury | 0.071 | |
| East Hartford | 0.071 | |
| Stafford | 0.071 |
Maine
| Monitor Location | Date/AQI Map | Concentration (ppm) |
|---|---|---|
Massachusetts
| Monitor Location | Date/AQI Map | Concentration (ppm) |
|---|---|---|
| Monitor Location | Date/AQI Map | Concentration (ppm) |
|---|---|---|
| Summit | March 15, 2025 Peak Ozone AQI Map | 0.075 |
Rhode Island
| Monitor Location | Date/AQI Map | Concentration (ppm) |
|---|---|---|
Vermont
| Monitor Location | Date/AQI Map | Concentration (ppm) |
|---|---|---|
| Underhill | March 15, 2025 Peak Ozone AQI Map | 0.073 |