# Arizona air quality today — live AQI by metro > Source: https://breathecheck.com/air-quality/us/arizona/ > Live AQI for 3 Arizona metros, updated hourly from EPA AirNow. Where the state's air is worst right now, and how far apart its cities are. # Arizona air quality today Updated 14 Sep 2026, 22:12 UTC · LIVE 3 metros tracked Across the 3 Arizona metros BreatheCheck measures, air is worst right now in Phoenix at AQI 66 (Moderate) and cleanest in Scottsdale at AQI 37 . That is a 29 -point spread inside one state — a state-level number would hide it, which is why this page does not publish one. ## Which Arizona city has the worst air quality right now? | # | Metro | AQI | UV now | Dominant | | 1 | Phoenix | 66 Moderate | 4.2 | PM10 | | 2 | Tucson | 44 Good | 3.8 | O3 | | 3 | Scottsdale | 37 Good | 4.2 | O3 | ## What is the UV index in Arizona today? The strongest UV in Arizona today is 9.1 (Very High) in Tucson, arriving around 12pm local time. The mildest of the 3 metros we model here peaks at 8.3 in Scottsdale. UV is modelled, not measured — unlike the AQI above it, which comes off an instrument. Hour by hour in Tucson → ## Coarse dust and ozone in one desert basin Two federal standards fail in the same desert basin for unrelated reasons. Phoenix occupies a broad, low floor ringed by higher ground, and the ground itself supplies the first problem: the Maricopa County area is a serious nonattainment area for PM-10, coarse particles that here mean mineral dust off bare desert soil, disturbed lots and unpaved surfaces, plus the dust storms that arrive with the summer monsoon. The plan the Maricopa Association of Governments and the Arizona Department of Environmental Quality submitted in 2012 was built around cutting PM-10 by five percent a year. Ozone is the second problem and runs on its own calendar. EPA designated Phoenix-Mesa nonattainment for the 2015 ozone standard in 2018 and reclassified it from marginal to moderate in 2022. The agency then proposed in November 2025, and finalized in March 2026, a determination not to move it to serious, concluding the area would have met the standard by its August 2024 deadline if emissions originating outside the United States had not been in the air. Some of what the monitors here record sits beyond the reach of any Arizona rule. The cool months bring a third source, and the only one that arrives as an instruction to a household. Under the county’s residential woodburning restriction ordinance, the Maricopa County Air Quality Department declares No Burn Days prohibiting wood burning in residential fireplaces, chimineas and outdoor fire pits, while ADEQ issues High Pollution Advisories for PM-10 and for ozone separately. A dust plan measured in percent per year and a federal finding about foreign emissions both run in years. The No Burn Day decides one evening. ## Where do these Arizona readings come from? 3 of the 3 metros here report from a named regulatory monitor — Phoenix, Tucson, Salt River Pima-Maricopa Indian Community. The dominant pollutant across Arizona today is PM10 in some metros, O3 in others. We track 3 metropolitan areas in Arizona, not the whole state, and 3 of them have a page of its own. There is no state-wide average here on purpose: averaging 3 metros into one figure would invent a value for all the ground between them. How we measure, and what we refuse to estimate → ## Neighbouring states Smoke and inversions do not stop at a state line, so when Arizona looks wrong the answer is often next door. ## Related Updated 14 Sep 2026, 22:12 UTC