Highlights
- The West Phoenix monitoring station recorded PM10 at 1,919.0 µg/m³ at 7 a.m. Tuesday, Aug. 4.
- PM2.5 simultaneously hit 174.4 µg/m³, also above the unhealthy-for-sensitive-groups threshold.
- Maricopa County Air Quality Department is the reporting agency; current conditions are posted on AirNow.
- Residents can sign up for High Pollution Advisory alerts through Maricopa County's notification system.
The West Phoenix air quality monitoring station (AQS site ID 040130019), operated by the Maricopa County Air Quality Department, recorded PM10 at 1,919.0 µg/m³ at 7 a.m. Tuesday, Aug. 4, a level that crosses AirNow's unhealthy-for-sensitive-groups breakpoint for coarse particulate matter.
PM2.5 at the same station simultaneously measured 174.4 µg/m³, also above the unhealthy-for-sensitive-groups threshold. Other pollutants at the hour were CO at 0.0 PPM, NO2 at 1.0 PPB, and ozone at 43.0 PPB.
The reading was reported through the EPA AirNow public hourly aggregate. Current forecasts and any active alerts for the Phoenix area are available at AirNow's Phoenix page. Maricopa County residents can also enroll in the county's Rapid Response Notification System to receive text or email alerts when a High Pollution Advisory is issued or when dust levels rise at selected monitoring locations.
For health guidance specific to current conditions, consult the Maricopa County Air Quality Department directly. Updated hourly readings will reflect whether levels have improved through the morning.
Sources
Every factual claim in this article traces to one of the sources below. See how we work for the editorial process.
- 040130019 retrieved 04/08/2026 08:48
- Maricopa County retrieved 04/08/2026 08:48
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 04/08/2026 08:48. Every claim traces to a source.
