Median AQI
45
Good
Wyoming · County air quality · 2025
Teton County, Wyoming
Median AQI 45 (Good). 79.2% of monitored days rated Good, direct from EPA Air Quality System stations.
- 45
- Median AQI
- 79.2%
- Good-air days
- 0
- Unhealthy days
- 50%
- Cleaner than US counties
The verdict
According to EPA Air Quality System monitoring data, Teton County's air is good on balance, cleaner than the median US county, a median AQI of 45 with 79.2% of 226 monitored days in the Good band, driven mainly by Ozone.
- 45
- median AQI · Good
- 79.2%
- days rated Good
- Ozone
- main pollutant
- 50%
- cleaner than US counties
Not one day crossed into the Unhealthy tier; the worst single reading was AQI 84.
Data updated July 2026
- Good · 179 d · 79.2%
- Moderate · 47 d · 20.8%
How did Teton County's air break down in 2025?
Across 226 monitored days, 179 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 84 (Moderate).
EPA AQS →Air quality data from EPA Air Quality System (2025). 226 days monitored. Median AQI: 45 (Good).
Insights: Teton County, Wyoming. EPA monitors recorded a median Air Quality Index of 45 across 226 measured days in 2025, earning a Good classification and a Good health grade. Of those days, 179 (79%) fell in the Good band (AQI 0–50), 47 (21%) registered Moderate readings, and 0 (0%) reached Unhealthy for Sensitive Groups. The 90th-percentile AQI settled at 58, while the worst single-day peak hit 84 (Moderate). Residents averaged about 23.8 clean-air days per 30-day window during the monitoring year.
The full pollutant mix ranks as Ozone (221 days), PM2.5 (3 days), CO (2 days). Across the 2020–2025 trend window, good days shifted by -133 and the median AQI moved +2 points, placing the multi-year trajectory at worsening. The worst single reading over the 2020–2025 window was AQI 84, moderate but never Unhealthy. Nearby counties show comparable readings: Albany (51.9% good, AQI 50); Campbell (77.3% good, AQI 43); Carbon (100.0% good, AQI 7); Converse (94.5% good, AQI 41); Fremont (61.3% good, AQI 48); Johnson (90.6% good, AQI 42).
Air Quality Summary
Good Days
79.2%
179 of 226 monitored days
4.2pp vs 75% target
Max AQI Recorded
84
Moderate
Health Grade
Good
90th-pct AQI 58
Teton County, Good days share 79.2%
National avg
Share of monitored days at AQI 0-50 (Good band).
Teton 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 226 monitored days across EPA AQI categories.
Good
179
79%
Moderate
47
21%
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 Teton County.
- Ozone · 221 days · 97.8%
- PM2.5 · 3 days · 1.3%
- CO · 2 days · 0.9%
Health Impact Assessment
Good
Teton County's air quality is rated Good based on 79.2% good air days. No unhealthy air days were recorded in 2025.
Air quality was acceptable on 79.2% 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 Ozone, driving AQI on 221 of 226 monitored days.
5-Year Air Quality Trend
Air quality is worsening in Teton County. Best year: 2022 (332 good days).
| Year | Good | Moderate | USG | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|---|
| 2020 | 312 | 42 | 7 | 5 | 43 | 165 |
| 2021 | 277 | 78 | 10 | 0 | 44 | 131 |
| 2022 | 332 | 33 | 0 | 0 | 43 | 100 |
| 2023 | 321 | 44 | 0 | 0 | 43 | 75 |
| 2024 | 276 | 88 | 2 | 0 | 44 | 138 |
| 2025 | 179 | 47 | 0 | 0 | 45 | 84 |
How does Teton County compare?
How Teton County compares
Good-day share better than US avg
Teton County 79.2%
Albany County, Wyoming 51.9%
US average 76.5%
Median AQI worse than US avg
Teton County 45
Albany County, Wyoming 50
US average 38
Unhealthy days / yr about average
Teton County 0
Albany County, Wyoming 0
US average 0
Other Counties in Wyoming
Air quality comparison for nearby counties in Wyoming.
Counties with Similar Air Quality
Counties across the US with a similar median AQI to Teton County.
Adair County, Oklahoma
AQI 45 · 59.2% good
Allen County, Indiana
AQI 45 · 58.2% good
Atascosa County, Texas
AQI 45 · 58.0% 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
What Teton County's air means for you
The air here stays in the breathable range year-round, with Ozone the main thing to watch.
- Sensitive groups (asthma, heart conditions, children, older adults) should check the AQI on high-Ozone days, the guide explains what a median of 45 means for exposure. Health guidance
- See how Teton County ranks against every monitored U.S. county on Good-day share. County rankings
- Compare Teton County with its Wyoming neighbours before drawing a conclusion about the region. All of Wyoming
Based on 226 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 Teton County, Wyoming? ▼
Teton County has a median Air Quality Index (AQI) of 45, rated "Good." 79.2% of monitored days (179 out of 226) had good air quality in 2025.
What is the main pollutant in Teton County? ▼
The primary pollutant in Teton County is Ozone (O3), which was the main AQI driver on 221 days (98% of monitored days). Can trigger asthma, reduce lung function, and cause chest pain.
How many unhealthy air days does Teton County have? ▼
In 2025, Teton County recorded 0 unhealthy air days (0 Unhealthy, 0 Very Unhealthy, 0 Hazardous). The maximum AQI reached 84.
Is the air quality in Teton County getting better or worse? ▼
Air quality in Teton County is worsening based on 5-year trends (2020-2025). Best year: 2022 with 332 good days. Worst year: 2025 with 179 good days.
What does AQI 45 mean for health? ▼
Teton 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 Teton County compare to other counties in Wyoming? ▼
Teton County has 79.2% good air days. Nearby counties in Wyoming: Albany (51.9% good), Campbell (77.3% good), Carbon (100.0% good), Converse (94.5% good), Fremont (61.3% good), Johnson (90.6% good).
What is the 90th percentile AQI in Teton County? ▼
The 90th percentile AQI for Teton County is 58, meaning 90% of monitored days had an AQI at or below this level. The maximum AQI recorded was 84 (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.