Air Quality in Tucson, Arizona — Live

Live readings from PurpleAir sensors across Tucson — with free alerts the moment the air turns.

Live Tucson AQI from nearby PurpleAir sensors loads when this page opens in a browser, along with a live sensor map covering Tucson and Oro Valley, Marana, Sahuarita, Green Valley.

Tucson sits in its own basin, ringed by the Santa Catalinas, Rincons, Santa Ritas and Tucson Mountains, and its air is measurably better than the Valley's up north. The University of Arizona's MAP Dashboard, working from EPA data, put Tucson at 33.7 per cent Good air quality days in 2025 against 6.6 per cent for Phoenix, with 97.8 per cent of days Good or Moderate. The American Lung Association's 2026 State of the Air report ranks Tucson-Nogales 41st worst in the country for ozone and 53rd for short-term particle pollution, well behind Phoenix-Mesa at fourth and 17th. What Tucson has instead of a chronic problem is a handful of sharp events — fires in the mountains it looks at every day, and dust that arrives with the monsoon.

Canairy watches the sensors around your home, your kids' school, and everywhere else you care about, and tells you in plain English when the air changes enough to matter.

The Catalinas burn, and Tucson breathes it

A lightning strike at 9.46pm on 5 June 2020 started the Bighorn Fire in the Santa Catalina Mountains. It burned 119,987 acres before being declared out on 23 July, forcing evacuations first in the Catalina Foothills, then Oro Valley, then Mount Lemmon and Summerhaven on 16 June. Seven people were injured and suppression cost roughly $37 million. Crews were slowed by rugged terrain, high winds and invasive buffelgrass — an African grass planted across Arizona from the 1930s for erosion control and cattle forage, which now fills the gaps between native desert plants and carries fire across ground that historically did not burn.

It was not the first. The Aspen Fire started on 17 June 2003 on Mount Lemmon, burned 84,750 acres before containment on 12 July, and destroyed 340 homes and businesses in Summerhaven. Both fires burned in mountains that rise directly above the north and east edge of the city, which is why a Catalina fire is not a distant news story here — it is a month or more of smoke you can see from your driveway.

Monsoon dust is the other half of the story

Tucson's dust does not always come from Tucson. On 20 June 2024 a haboob that National Weather Service meteorologist Jason Laney described as roughly 200 miles across formed over southern New Mexico and west Texas and pushed into Arizona. Tucson recorded gusts to 36 mph, hit 109 degrees, and watched PM10 climb from moderate in the morning to a brief spike into the orange, unhealthy-for-sensitive-groups band at the storm's peak.

The traffic runs the other way too. The outflows behind the famous 5 July 2011 haboob — the one that pushed peak hourly PM10 to 1,974 micrograms per cubic metre at EPA monitors near Phoenix — formed from thunderstorms southeast of Tucson before merging on their way northwest. In between, the ten-mile stretch of I-10 between Eloy and Picacho Peak is dangerous enough in blowing dust that ADOT installed 13 visibility sensors and variable speed signs there, able to drop the posted 75 mph limit as low as 35.

Pima County meets the standards nearly everywhere — with one exception

Pima County is in attainment of every federal ambient air quality standard except in one place: the Rillito area northwest of Tucson, which remains nonattainment for PM10. The county attributes that to nearby agricultural land, emissions from Arizona Portland Cement, and fugitive dust thrown up by vehicle traffic. Tucson itself sits under a limited maintenance plan for carbon monoxide, a leftover from the years when winter CO was the city's headline pollutant.

For everything else, the county's own emissions inventory points at the obvious culprit and one less obvious one: on-road motor vehicles are the largest source of nitrogen oxides in Pima County at 46.5 per cent of the total, while 80.9 per cent of volatile organic compounds come from natural, biogenic sources — the desert itself. Pima County DEQ runs 15 electronically polled monitoring stations across eastern Pima County including the Tucson metro area and Green Valley, and since July 2023 has also run a school-based sensor programme measuring particulates, carbon monoxide, ozone and nitrogen oxides on campuses.

Tucson air quality FAQ

Why is there smoke or dust in Tucson today?

In June and early July, check the mountains. Fires in the Santa Catalinas have twice put Tucson under weeks of smoke — the Aspen Fire in 2003, which burned 84,750 acres, and the Bighorn Fire in 2020, which burned 119,987 — and the Rincons and Santa Ritas carry the same risk. From late June through September the more likely answer is dust: monsoon outflows lift walls of it, sometimes from hundreds of miles away, as on 20 June 2024 when a haboob formed over New Mexico and west Texas and pushed Tucson's PM10 briefly into the unhealthy-for-sensitive-groups range. Dust events rise and fall fast. Smoke tends to linger.

What is the air quality in Tucson right now?

This page shows the current AQI for Tucson from PurpleAir sensors across the city, updated continuously. Readings vary across the basin — the foothills under the Catalinas, midtown, and the south and west sides toward Avra Valley can differ noticeably during a dust event — so the map below shows every live sensor and you can find the one closest to you. Pima County DEQ also runs 15 regulatory monitoring stations across eastern Pima County.

Is Tucson's air better than Phoenix's?

By the numbers, yes. The University of Arizona's MAP Dashboard recorded 33.7 per cent Good air quality days for Tucson in 2025, against 6.6 per cent for Phoenix, and the American Lung Association's 2026 report ranks Tucson-Nogales 41st worst in the country for ozone while Phoenix-Mesa sits fourth. Pima County meets all federal standards except in the Rillito area northwest of the city, still nonattainment for PM10. That does not mean Tucson has no bad days — 2025 still had 1.6 per cent of days rated unhealthy for sensitive groups and another 0.3 per cent very unhealthy or hazardous.

When is Tucson's air usually worst?

Two windows. Fire season runs from roughly May into early July, before the monsoon breaks — the Bighorn Fire started on 5 June 2020 and was not out until 23 July. Then the monsoon itself, June through September, brings the dust. Ozone is a smaller but real concern; Pima County notes that ozone standards were exceeded several times during the 2018 and 2020 ozone seasons. Winter is generally the calmer part of the year here, which is the reverse of how it works in Phoenix.

What AQI level is unhealthy?

Under the US EPA scale, AQI 0–50 is Good and 51–100 is Moderate. From 101 the air is Unhealthy for Sensitive Groups — kids, older adults, and people with asthma or heart conditions — and above 150 it's Unhealthy for everyone. Canairy translates these numbers into a plain-English verdict, like whether to close the windows or move a workout indoors.

Is Canairy free?

Yes. The Canairy app is free to download and includes live air quality for all your saved places, plain-English verdicts, and free push alerts when the air crosses your threshold. A paid plan adds extras like SMS text alerts.

Get Canairy free on Google Play.