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2025 Ozone Exceedances

(Through March 15, 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.

Learn more about Ozone.

On this page:

Connecticut
Maine
Massachusetts
New Hampshire
Rhode Island
Vermont

Connecticut

Monitor Location	Date/AQI Map	Concentration (ppm)

Maine

Monitor Location	Date/AQI Map	Concentration (ppm)

Massachusetts

Monitor Location	Date/AQI Map	Concentration (ppm)

New Hampshire
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