System Maintenance 7:30 pm EDT, 4/21, to 2:30 am EDT, 4/22

Tags: #<Tag:0x00007f5879c68c10> #<Tag:0x00007f5879c689e0> #<Tag:0x00007f5879c688c8>

The AirNow Data Management Center will be performing system maintenance from 7:30 pm EDT on Thursday, April 21 lasting until 2:30 am EDT on Friday, April 22.

During this time, the new ozone NowCast will be deployed, which will be replacing the ozone surrogate. Furthermore, daily maximum 8-hour average ozone will be adjusted to only include begin time 8-hour averages from 07:00-23:00 LST to align with the NAAQS.

The AirNow-Tech, AirNow API, and EnviroFlash websites will not be accessible during the maintenance window. Data feeds and products will not update or be delayed until maintenance is completed.

We apologize for any inconvenience caused. For any questions or concerns, please email

Thank you.
EPA and AirNow Data Management Center