Metro area air quality · 2025
Phoenix-Mesa-Scottsdale, AZ
Median AQI 78 (Moderate). 6.6% of monitored days rated Good across this metro's EPA monitoring network.
- 78
- Median AQI
- 6.6%
- Good-air days
- 13
- Unhealthy days
- 0%
- Cleaner than US metros
Phoenix-Mesa-Scottsdale, AZ posted a 2025 median AQI of 78 (Moderate) with 6.6% Good days
According to the U.S. EPA Air Quality System, the Phoenix-Mesa-Scottsdale, AZ CBSA recorded a median AQI of 78 across 365 monitored days in 2025, with 6.6% rated Good and 13 unhealthy or worse. This is an annual metro comparison, not a live advisory.
Data source EPA Air Quality System (AQS)
- Cleaner than US metros
- The Phoenix-Mesa-Scottsdale, AZ CBSA's 6.6% Good-day share places it cleaner than 0% of US metros in 2025.
- Closest median-AQI peer
- Los Angeles-Long Beach-Anaheim, CA (10.7% Good, median AQI 74) is the closest nationwide median-AQI peer to Phoenix-Mesa-Scottsdale, AZ.
- 2020–2025 Good-day shift
- Phoenix-Mesa-Scottsdale, AZ's Good-day share moved +4.3 points from 2020 to 2025 (median AQI -42).
- Median AQI
- Median AQI: 78
Aggregated from EPA Air Quality System (2025), 365 monitored days. EPA AQS →
The verdict
Phoenix-Mesa-Scottsdale, AZ lands in the lower Good-day tercile (6.6% Good), a thinner clean-air share than most CBSA peers here. On the EPA scale the metro runs moderate, among the more polluted US metros, with a median AQI of 78 and 6.6% of 365 monitored days in the Good band.
- 78
- median AQI · Moderate
- 6.6%
- days rated Good
- 0%
- cleaner than US metros
- 1215
- worst single reading
13 days reached Unhealthy or worse across the metro's monitors in 2025.
Annual release change
What changed in the 2025 EPA annual release
- Phoenix-Mesa-Scottsdale, AZ metro's peak single-day AQI rose from 337 to 1215 between the 2024 and 2025 EPA annual releases, a change of +878 points.
- Phoenix-Mesa-Scottsdale, AZ metro's Unhealthy-category days fell from 9 to 3 between the 2024 and 2025 EPA annual releases, a change of -6 days.
- Phoenix-Mesa-Scottsdale, AZ metro's median AQI fell from 86 to 78 between the 2024 and 2025 EPA annual releases, a change of -8 points.
- Phoenix-Mesa-Scottsdale, AZ metro's Good-day share fell from 9.6% to 7.7% between the 2024 and 2025 EPA annual releases, a change of -1.9 percentage points.
Phoenix-Mesa-Scottsdale, AZ lands in the lower Good-day tercile (6.6% Good), a thinner clean-air share than most CBSA peers here. Signature read: 6.6% Good-day share (low tercile vs CBSA corpus). Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 78 over 365 measured days in 2025 (Moderate / Very Poor). The monitored-day split lands at 24 Good (7%), 285 Moderate (78%), and 43 Unhealthy-for-Sensitive-Groups (12%). The 90th-percentile AQI finished at 108; the highest single-day reading hit 1215 (Hazardous).
Across 2020–2025, Good-day share shifted +4.3 points and median AQI moved -42 (improving). The annual record contains 13 days at Unhealthy or worse. Metros with comparable AQI profiles include Los Angeles-Long Beach-Anaheim, CA (10.7% good, AQI 74); Bakersfield, CA (17.5% good, AQI 70); El Paso, TX (18.1% good, AQI 70).
Air Quality Summary
Median AQI
78
Moderate
Good Days
6.6%
24 of 365 days
Max AQI
1215
Hazardous
Health Grade
Very Poor
90th pct: 108
AQI Day Breakdown (2025)
Distribution of 365 monitored days across EPA AQI categories.
Good
24
7%
Moderate
285
78%
USG
43
12%
Unhealthy
3
1%
Very Unhealthy
1
0%
Hazardous
9
2%
Health Impact Assessment
The Phoenix-Mesa-Scottsdale, AZ metro area's air quality is rated Very Poor based on 6.6% good air days. There were 13 unhealthy days in 2025 when outdoor activity should be limited.
Air quality posed significant health risk in 2025. Sensitive groups, including people with asthma, COPD, cardiovascular conditions, children, pregnant women, and adults over 65, should monitor AirNow.gov alerts and limit outdoor activity on Unhealthy (AQI 151+) and Very Unhealthy (201+) days. Peak readings reached AQI 1215, beyond EPA's standard 0-500 scale, indicating an extreme event.
Sensitive group advisory
People with asthma, COPD, heart disease, children, pregnant women, and adults 65+ should follow EPA AQI alerts daily and limit outdoor exertion when AQI exceeds 100. Real-time conditions: airnow.gov.
Note: EPA's standard AQI scale caps at 500. The 1215 peak reading represents an extreme event extrapolated beyond the index's design range. See EPA wildfire smoke guidance.
How does the Phoenix-Mesa-Scottsdale, AZ metro compare?
How Phoenix-Mesa-Scottsdale, AZ compares
5-Year Air Quality Trend
Air quality is improving in the Phoenix-Mesa-Scottsdale, AZ metro. Highest Good-day share: 2023 (10.7%, 31 of 290 monitored days).
| Year | Good | Moderate | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|
| 2020 | 7 | 128 | 69 | 120 | 1194 |
| 2021 | 9 | 118 | 63 | 125 | 297 |
| 2022 | 21 | 236 | 19 | 79 | 689 |
| 2023 | 31 | 249 | 10 | 78 | 709 |
| 2024 | 25 | 227 | 9 | 86 | 337 |
| 2025 | 24 | 285 | 3 | 78 | 1215 |
Metros with a similar median AQI
CBSA peers nationwide whose annual median AQI sits near Phoenix-Mesa-Scottsdale, AZ (78).
Los Angeles-Long Beach-Anaheim, CA
Median AQI 74 · 10.7% Good-day share
Bakersfield, CA
Median AQI 70 · 17.5% Good-day share
El Paso, TX
Median AQI 70 · 18.1% Good-day share
Riverside-San Bernardino-Ontario, CA
Median AQI 87 · 7.4% Good-day share
San Diego-Carlsbad, CA
Median AQI 67 · 17.5% Good-day share
El Centro, CA
Median AQI 64 · 27.7% Good-day share
Metros with similar unhealthy-day exposure
A second relationship type: metros whose unhealthy-or-worse day count is closest to Phoenix-Mesa-Scottsdale, AZ's 13 (independent of median AQI).
Duluth, MN-WI
12 unhealthy-or-worse days · median AQI 42
Houston-The Woodlands-Sugar Land, TX
11 unhealthy-or-worse days · median AQI 63
Fairbanks, AK
10 unhealthy-or-worse days · median AQI 44
Bemidji, MN
9 unhealthy-or-worse days · median AQI 36
Deming, NM
9 unhealthy-or-worse days · median AQI 17
Wenatchee, WA
9 unhealthy-or-worse days · median AQI 35
Frequently Asked Questions
How many unhealthy air days does Phoenix-Mesa-Scottsdale, AZ have? ▼
What is the air quality in the Phoenix-Mesa-Scottsdale, AZ metro area? ▼
Is air quality in Phoenix-Mesa-Scottsdale, AZ getting better or worse? ▼
What does AQI 78 mean for health? ▼
How does Phoenix-Mesa-Scottsdale, AZ compare to other metro areas? ▼
What is the 90th percentile AQI for Phoenix-Mesa-Scottsdale, AZ? ▼
Data Sources
Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset for Phoenix-Mesa-Scottsdale, AZ, 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, Phoenix-Mesa-Scottsdale, AZ · 2020–2025