Metro area air quality · 2025

Nogales, AZ

Median AQI 45 (Good). 63.6% of monitored days rated Good across this metro's EPA monitoring network.

45
Median AQI
63.6%
Good-air days
1
Unhealthy days
31%
Cleaner than US metros

Aggregated from EPA Air Quality System (2025), 272 monitored days. EPA AQS →

The verdict

The Nogales, AZ metro runs good on the EPA scale, more polluted than the median US metro, a median AQI of 45 with 63.6% of 272 monitored days in the Good band.

45
median AQI · Good
63.6%
days rated Good
31%
cleaner than US metros
187
worst single reading

1 day reached Unhealthy or worse across the metro's monitors in 2025.

Insights: Nogales, AZ metro. Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 45 over 272 measured days in 2025, which corresponds to a Good band and a Moderate metro-wide health grade. The monitored-day split lands at 173 Good days (64%), 97 Moderate (36%), and 1 Unhealthy-for-Sensitive-Groups (0%). The 90th-percentile AQI finished at 64 while the highest single-day reading hit 187 (Unhealthy). Metro residents averaged roughly 19.1 clean-air days per 30-day window across the reporting year.

Across the 2020–2025 trend window, good days shifted by -35 and the median AQI moved +1 points, which classifies the multi-year trajectory as improving. The metro recorded 1 unhealthy-or-worse days combined, on those days the EPA recommends that sensitive groups limit prolonged outdoor exertion, and many schools and athletic programs adjust outdoor activity accordingly. Metros with comparable AQI profiles include Akron, OH (62.2% good, AQI 45); Carson City, NV (79.3% good, AQI 45); Clinton, IA (59.9% good, AQI 45).

Air Quality Summary

Median AQI

45

Good

Good Days

63.6%

173 of 272 days

Max AQI

187

Unhealthy

Health Grade

Moderate

90th pct: 64

AQI Day Breakdown (2025)

Distribution of 272 monitored days across EPA AQI categories.

Good

173

64%

Moderate

97

36%

USG

1

0%

Unhealthy

1

0%

Very Unhealthy

0

0%

Hazardous

0

0%

Health Impact Assessment

Moderate

The Nogales, AZ metro area's air quality is rated Moderate based on 63.6% good air days. There were 1 unhealthy days in 2025 when outdoor activity should be limited.

Air quality is acceptable most days, but 1 days reached "Unhealthy for Sensitive Groups" and peak AQI reached 187. Sensitive groups should monitor real-time conditions at AirNow.gov.

How does the Nogales, AZ metro compare?

How Nogales, AZ compares

Good-day share worse than US avg
Nogales, AZ 63.6%
Akron, OH 62.2%
US average 71.3%
Median AQI worse than US avg
Nogales, AZ 45
Akron, OH 45
US average 41
Unhealthy days / yr about average
Nogales, AZ 1
Akron, OH 0
US average 1

5-Year Air Quality Trend

Air quality is improving in the Nogales, AZ metro. Best year: 2023 (265 good days).

Year Good Moderate Unhealthy Median AQI
2020 208 147 1 44
2021 169 189 1 52
2022 220 136 0 43
2023 265 92 0 37
2024 213 139 0 43
2025 173 97 1 45

Metros with Similar Air Quality

Metro areas across the US with a similar median AQI to Nogales, AZ.

Akron, OH

AQI 45 · 62.2% good

45

Carson City, NV

AQI 45 · 79.3% good

45

Clinton, IA

AQI 45 · 59.9% good

45

Davenport-Moline-Rock Island, IA-IL

AQI 45 · 58.4% good

45

Española, NM

AQI 45 · 79.9% good

45

Gadsden, AL

AQI 45 · 63.5% good

45

More Air Quality Data

Explore EPA air quality rankings and guides across U.S. metros and counties.

Cleanest Metro Areas

U.S. metros ranked by their share of Good air-quality days.

Worst Air Quality

Counties and metros with the most unhealthy air days.

All Metro Areas

Annual AQI by CBSA for every monitored U.S. metro area.

Best and Worst City Air

What drives urban air quality and how metro areas compare.

Air Quality Guides

Frequently Asked Questions

What is the air quality in the Nogales, AZ metro area? ▼
The Nogales, AZ metro area has a median Air Quality Index (AQI) of 45, rated "Good." 63.6% of monitored days (173 out of 272) had good air quality in 2025.
How many unhealthy air days does Nogales, AZ have? ▼
In 2025, the Nogales, AZ metro area recorded 1 unhealthy air days (1 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 187.
Is air quality in Nogales, AZ getting better or worse? ▼
Air quality in the Nogales, AZ metro is improving based on 5-year trends (2020-2025). Best year: 2023 with 265 good days. Worst year: 2021 with 169 good days.
What does AQI 45 mean for health? ▼
An AQI of 45 is "Good", air quality is satisfactory and poses little or no health risk. This is the best category on the EPA's AQI scale.
What is the 90th percentile AQI for Nogales, AZ? ▼
The 90th percentile AQI for the Nogales, AZ metro area is 64, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 187 (Unhealthy).
How does Nogales, AZ compare to other metro areas? ▼
The Nogales, AZ metro has 63.6% good air days. Similar metros: Akron, OH (62.2% good), Carson City, NV (79.3% good), Clinton, IA (59.9% good).

Data Sources

Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset, 2020–2025. See our methodology for how AQI, median, and coverage figures are computed.

Read our methodology , how this data is sourced, computed, and verified.

Source: U.S. EPA Air Quality System (AQS) Annual AQI by CBSA summary files (metro-level) · 2020–2025

Every figure on PlainAir is rendered directly from EPA AQS air-quality monitoring data, no number is typed in by an editor. This page draws directly on EPA AQS air-quality monitoring data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.