Median AQI
45
Good
Texas · County air quality · 2025
Atascosa County, Texas
Median AQI 45 (Good). 58.0% of monitored days rated Good, direct from EPA Air Quality System stations.
- 45
- Median AQI
- 58.0%
- Good-air days
- 0
- Unhealthy days
- 12%
- Cleaner than US counties
The verdict
According to EPA Air Quality System monitoring data, Atascosa County's air is good on balance, among the more polluted 10% of US counties, a median AQI of 45 with 58.0% of 157 monitored days in the Good band, driven mainly by PM2.5.
- 45
- median AQI · Good
- 58.0%
- days rated Good
- PM2.5
- main pollutant
- 12%
- cleaner than US counties
Not one day crossed into the Unhealthy tier; the worst single reading was AQI 92.
Data updated July 2026
- Good · 91 d · 58.0%
- Moderate · 66 d · 42.0%
How did Atascosa County's air break down in 2025?
Across 157 monitored days, 91 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 92 (Moderate).
EPA AQS →Air quality data from EPA Air Quality System (2025). 157 days monitored. Median AQI: 45 (Good).
Insights: Atascosa County, Texas. EPA monitors recorded a median Air Quality Index of 45 across 157 measured days in 2025, earning a Good classification and a Moderate health grade. Of those days, 91 (58%) fell in the Good band (AQI 0–50), 66 (42%) registered Moderate readings, and 0 (0%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 71, while the worst single-day peak hit 92 (Moderate). Residents averaged about 17.4 clean-air days per 30-day window during the monitoring year.
The full pollutant mix ranks as PM2.5 (157 days). Across the 2020–2025 trend window, good days shifted by -58 and the median AQI moved +7 points, placing the multi-year trajectory at worsening. The worst single reading over the 2020–2025 window was AQI 92, moderate but never Unhealthy. Nearby counties show comparable readings: Bell (61.3% good, AQI 47); Bexar (39.8% good, AQI 53); Bowie (57.3% good, AQI 47); Brazoria (84.8% good, AQI 33); Brazos (63.4% good, AQI 43); Brewster (69.0% good, AQI 44).
Air Quality Summary
Good Days
58.0%
91 of 157 monitored days
-17.0pp vs 75% target
Max AQI Recorded
92
Moderate
Health Grade
Moderate
90th-pct AQI 71
Atascosa County, Good days share 58.0%
National avg
Share of monitored days at AQI 0-50 (Good band).
Atascosa County, Unhealthy-or-worse share 0.0%
National avg
Share of monitored days above AQI 150 (Unhealthy or worse). Bar maxes at 10% (worst-county ceiling).
AQI Day Breakdown (2025)
Distribution of 157 monitored days across EPA AQI categories.
Good
91
58%
Moderate
66
42%
USG
0
0%
Unhealthy
0
0%
Very Unhealthy
0
0%
Hazardous
0
0%
Pollutant Breakdown
Days where each pollutant was the primary driver of AQI readings in Atascosa County.
- PM2.5 · 157 days · 100.0%
Health Impact Assessment
Moderate
Atascosa County's air quality is rated Moderate based on 58.0% good air days. No unhealthy air days were recorded in 2025.
Air quality was acceptable on 58.0% of monitored days in 2025, with a median AQI of 45. Unusually sensitive people can check real-time conditions at AirNow.gov during high-pollution events.
The dominant pollutant is PM2.5, driving AQI on 157 of 157 monitored days.
5-Year Air Quality Trend
Air quality is worsening in Atascosa County. Best year: 2022 (218 good days).
| Year | Good | Moderate | USG | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|---|
| 2020 | 149 | 64 | 0 | 1 | 38 | 158 |
| 2021 | 213 | 143 | 0 | 0 | 43 | 87 |
| 2022 | 218 | 136 | 2 | 0 | 44 | 115 |
| 2023 | 210 | 120 | 0 | 0 | 42 | 86 |
| 2024 | 198 | 141 | 8 | 0 | 44 | 116 |
| 2025 | 91 | 66 | 0 | 0 | 45 | 92 |
How does Atascosa County compare?
How Atascosa County compares
Good-day share worse than US avg
Atascosa County 58.0%
Bell County, Texas 61.3%
US average 76.5%
Median AQI worse than US avg
Atascosa County 45
Bell County, Texas 47
US average 38
Unhealthy days / yr about average
Atascosa County 0
Bell County, Texas 0
US average 0
Other Counties in Texas
Air quality comparison for nearby counties in Texas.
Counties with Similar Air Quality
Counties across the US with a similar median AQI to Atascosa County.
Adair County, Oklahoma
AQI 45 · 59.2% good
Allen County, Indiana
AQI 45 · 58.2% good
Baker County, Florida
AQI 45 · 69.1% good
Carson City County, Nevada
AQI 45 · 79.3% good
Clinton County, Iowa
AQI 45 · 59.9% good
Comanche County, Oklahoma
AQI 45 · 63.8% good
What Atascosa County's air means for you
The air here stays in the breathable range year-round, with PM2.5 the main thing to watch.
- Sensitive groups (asthma, heart conditions, children, older adults) should check the AQI on high-PM2.5 days, the guide explains what a median of 45 means for exposure. Health guidance
- See how Atascosa County ranks against every monitored U.S. county on Good-day share. County rankings
- Compare Atascosa County with its Texas neighbours before drawing a conclusion about the region. All of Texas
Based on 157 EPA-monitored days in 2025; figures reflect only days the monitors reported. Source: EPA Air Quality System annual summaries.
More Air Quality Data
Air Quality Guides
Frequently Asked Questions
What is the air quality in Atascosa County, Texas? ▼
Atascosa County has a median Air Quality Index (AQI) of 45, rated "Good." 58.0% of monitored days (91 out of 157) had good air quality in 2025.
What is the main pollutant in Atascosa County? ▼
The primary pollutant in Atascosa County is Fine Particles (PM2.5), which was the main AQI driver on 157 days (100% of monitored days). Penetrates deep into lungs and bloodstream. Linked to heart disease and premature death.
How many unhealthy air days does Atascosa County have? ▼
In 2025, Atascosa County recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 92.
Is the air quality in Atascosa County getting better or worse? ▼
Air quality in Atascosa County is worsening based on 5-year trends (2020-2025). Best year: 2022 with 218 good days. Worst year: 2025 with 91 good days.
What does AQI 45 mean for health? ▼
Atascosa County's median AQI of 45 falls in the "Good" category. See the <a href="/guides/understanding-aqi" class="underline">AQI category guide</a> for what each range means for health.
How does Atascosa County compare to other counties in Texas? ▼
Atascosa County has 58.0% good air days. Nearby counties in Texas: Bell (61.3% good), Bexar (39.8% good), Bowie (57.3% good), Brazoria (84.8% good), Brazos (63.4% good), Brewster (69.0% good).
What is the 90th percentile AQI in Atascosa County? ▼
The 90th percentile AQI for Atascosa County is 71, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 92 (Moderate).
Data Sources
Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by County dataset, 2020–2025 (aqs.epa.gov). For current conditions (not shown here — this page is historical annual data), see EPA AirNow (airnow.gov). See our methodology for how AQI, median, and coverage figures are computed.
Informational only, not professional advice. Data from EPA AQS. See our disclaimer.
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.