Highlights
- The Central Phoenix air monitoring station recorded PM10 at 307.0 micrograms per cubic meter at 3 a.m. Tuesday, July 21.
- That reading crossed AirNow's unhealthy-for-sensitive-groups breakpoint for PM10 particulate matter.
- Maricopa County Air Quality Department operates the station; readers can track current conditions and any active alerts via AirNow's Phoenix page.
The Maricopa County Air Quality Department monitoring station in Central Phoenix recorded PM10 particulate matter at 307.0 micrograms per cubic meter at 3 a.m. Tuesday, July 21, according to EPA AirNow hourly aggregate data. That reading crossed AirNow's unhealthy-for-sensitive-groups breakpoint for PM10.
The same hour's readings at the station (AQS site ID 040133002) showed carbon monoxide at 0.1 PPM, nitrogen dioxide at 3.0 PPB, and ozone at 47.0 PPB.
Maricopa County operates a Rapid Response Notification System that sends email and text alerts when a High Pollution Advisory is issued or when dust levels rise at selected monitoring locations. Current conditions and any active advisories for the Phoenix area are available on AirNow's Phoenix page.
Sources
Every factual claim in this article traces to one of the sources below. See how we work for the editorial process.
- 040133002 retrieved 21/07/2026 04:19
- Maricopa County retrieved 21/07/2026 04:19
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 21/07/2026 04:19. Every claim traces to a source.
