Metro area air quality · 2025
St. Joseph, MO-KS
Median AQI 43 (Good). 64.2% of monitored days rated Good across this metro's EPA monitoring network.
- 43
- Median AQI
- 64.2%
- Good-air days
- 1
- Unhealthy days
- 32%
- Cleaner than US metros
Aggregated from EPA Air Quality System (2025), 148 monitored days. EPA AQS →
The verdict
The St. Joseph, MO-KS metro runs good on the EPA scale, more polluted than the median US metro, a median AQI of 43 with 64.2% of 148 monitored days in the Good band.
- 43
- median AQI · Good
- 64.2%
- days rated Good
- 32%
- cleaner than US metros
- 256
- worst single reading
1 day reached Unhealthy or worse across the metro's monitors in 2025.
Insights: St. Joseph, MO-KS metro. Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 43 over 148 measured days in 2025, which corresponds to a Good band and a Moderate metro-wide health grade. The monitored-day split lands at 95 Good days (64%), 52 Moderate (35%), and 0 Unhealthy-for-Sensitive-Groups (0%). The 90th-percentile AQI finished at 64 while the highest single-day reading hit 256 (Very Unhealthy). Metro residents averaged roughly 19.3 clean-air days per 30-day window across the reporting year.
Across the 2020–2025 trend window, good days shifted by -148 and the median AQI moved -1 points, which classifies the multi-year trajectory as stable. 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 Allentown-Bethlehem-Easton, PA-NJ (65.6% good, AQI 43); Amarillo, TX (75.7% good, AQI 43); Ashtabula, OH (81.2% good, AQI 43).
Air Quality Summary
Median AQI
43
Good
Good Days
64.2%
95 of 148 days
Max AQI
256
Very Unhealthy
Health Grade
Moderate
90th pct: 64
AQI Day Breakdown (2025)
Distribution of 148 monitored days across EPA AQI categories.
Good
95
64%
Moderate
52
35%
USG
0
0%
Unhealthy
0
0%
Very Unhealthy
1
1%
Hazardous
0
0%
Health Impact Assessment
The St. Joseph, MO-KS metro area's air quality is rated Moderate based on 64.2% good air days. There were 1 unhealthy days in 2025 when outdoor activity should be limited.
Air quality reached unhealthy levels on 1 days in 2025 (0 Unhealthy, 1 Very Unhealthy). Sensitive groups, including people with asthma, COPD, cardiovascular conditions, children, and adults over 65, should review the daily breakdown and follow local advisories.
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.
How does the St. Joseph, MO-KS metro compare?
How St. Joseph, MO-KS compares
5-Year Air Quality Trend
Air quality is stable in the St. Joseph, MO-KS metro. Best year: 2020 (243 good days).
| Year | Good | Moderate | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|
| 2020 | 243 | 122 | 0 | 44 | 126 |
| 2021 | 230 | 132 | 0 | 44 | 109 |
| 2022 | 227 | 135 | 0 | 46 | 106 |
| 2023 | 182 | 175 | 0 | 51 | 129 |
| 2024 | 202 | 157 | 0 | 48 | 100 |
| 2025 | 95 | 52 | 0 | 43 | 256 |
Metros with Similar Air Quality
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Worst Air Quality
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All Metro Areas
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Air Quality Guides
Frequently Asked Questions
What is the air quality in the St. Joseph, MO-KS metro area? ▼
How many unhealthy air days does St. Joseph, MO-KS have? ▼
Is air quality in St. Joseph, MO-KS getting better or worse? ▼
What does AQI 43 mean for health? ▼
What is the 90th percentile AQI for St. Joseph, MO-KS? ▼
How does St. Joseph, MO-KS compare to other metro areas? ▼
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.