Explore Data on Air Quality in Tucson, Arizona MSA

How are we doing?

Percent of Good Air Quality Days (2025)

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In 2025, air quality in the Tucson Metropolitan Statistical Area (MSA) was rated “good” 33.7% of the time. Among 12 western peer MSAs, Tucson ranked fifth-highest in the share of days with good air quality. Portland ranked first at 69.9%, while Phoenix ranked last at only 6.6%. According to the Air Quality Index (AQI), "good" quality days occur when air quality is satisfactory, and air pollution poses little or no health risk. The AQI categorizes air quality into six levels: good, moderate, unhealthy for sensitive groups, unhealthy, very unhealthy, and hazardous. Tucson’s share of good air quality days improved from 30.9% in 2024 to 33.7% in 2025. While conditions improved modestly over the year, regional dust events and wildfire smoke continued to impact air quality conditions across the Tucson MSA in recent years.

Why is it important?

Air quality is an important component of regional well-being and can have significant implications for public health, the environment, and the economy. Poor air quality can pose increased risks for individuals with respiratory conditions and other health sensitivities, while contributing to lost productivity due to illness. In addition, air pollution can cause damage to buildings, vegetation, and crops. A range of factors influences air quality, including traffic congestion, wildfire smoke, dust events, and pollution from industrial factories and refineries.

How do we compare?

In 2025, 97.8% of days in the Tucson MSA were classified as having either good or moderate air quality. An additional 1.6% days were categorized as unhealthy for sensitive groups, while 0.3% were classified as either very unhealthy or hazardous. Among western MSAs, Phoenix reported the highest share of unhealthy air days in 2025, and El Paso recorded the highest percentage of days classified as very unhealthy or hazardous. According to a report by the American Lung Association, elevated ozone levels are associated with consistently warm temperatures and can be harder to clean up. "Very unhealthy" air quality days trigger a health alert indicating increased risk of adverse health effects for the general population, while "hazardous" days represent an emergency warning.

What are the key trends?

The share of air quality days rated “good” in the Tucson MSA has fluctuated in recent years, reaching a peak of 64.7% in 2015 before declining to a 20-year low of 25.5% in 2021. Conditions improved in 2022, when 40.3% of days were considered good, before decreasing to 33.7% in 2025. Tucson ranked fifth among 12 peer western MSAs in 2025, improving from sixth in 2024. In contrast, Phoenix ranked last, with only 6.6% of days classified as “good”. This represented a gap of more than 27 percentage points between the two MSAs. Phoenix continues to face air quality challenges relative to the rest of the nation.

How is it measured?

Air quality data come from the U.S. Environmental Protection Agency’s Air Quality Index Report, an annual summary of AQI values for four major air pollutants. However, many areas lack monitoring stations for all pollutants. The AQI has a range of 0-500 broken down into six levels: good (0-50), moderate (51-100), unhealthy for sensitive groups (101-150), unhealthy (151-200), very unhealthy (201-300), and hazardous (301-500). The EPA updated the AQI for ozone in 2024, and the update applied to all historical data.