Highlights
- The Fountain Hills AQS monitor recorded ozone at 73.0 ppb at 7 p.m. Wednesday, July 16.
- That reading crossed AirNow's Unhealthy for Sensitive Groups breakpoint for ozone.
- The reading is reported by the Maricopa County Air Quality Department via the EPA AirNow network.
- Readers can check current conditions and active alerts at AirNow's Phoenix-area page.
The ozone monitor at Fountain Hills recorded 73.0 parts per billion at 7 p.m. Wednesday, July 16, crossing the AirNow threshold designated Unhealthy for Sensitive Groups, according to the EPA AirNow public hourly aggregate reported by the Maricopa County Air Quality Department.
The reading came from AQS site ID 040139704, the Fountain Hills monitoring station operated within the Maricopa County network. The Unhealthy for Sensitive Groups designation applies when ozone concentrations reach levels that may affect children, older adults, and individuals with heart or lung conditions, according to the Maricopa County Air Quality Department.
For current conditions, forecast, and any active advisories, readers can visit AirNow's Phoenix-area page. For guidance specific to Maricopa County, the department can be reached through its official page or via the Fountain Hills municipal air quality resource, which lists the county contact line.
The AirNow Phoenix-area page will reflect any updated readings or advisories as conditions change through the evening.
Sources
Every factual claim in this article traces to one of the sources below. See how we work for the editorial process.
- 040139704 retrieved 16/07/2026 20:19
- Maricopa County retrieved 16/07/2026 20:19
- fountainhillsaz.gov retrieved 16/07/2026 20:19
Authored by The Scottsdale Signal. Drafted by AI from primary-source material under our beat-specific editorial guides; reviewed by humans before publish under our five-gate process. Sources retrieved at 16/07/2026 20:19. Every claim traces to a source.
