Metro area air quality · 2025
Riverton, WY
Median AQI 47 (Good). 69.6% of monitored days rated Good across this metro's EPA monitoring network.
- 47
- Median AQI
- 69.6%
- Good-air days
- 0
- Unhealthy days
- 44%
- Cleaner than US metros
Riverton, WY posted a 2025 median AQI of 47 (Good) with 69.6% Good days
According to the U.S. EPA Air Quality System, the Riverton, WY CBSA recorded a median AQI of 47 across 365 monitored days in 2025, with 69.6% rated Good and 0 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 Riverton, WY CBSA's 69.6% Good-day share places it cleaner than 44% of US metros in 2025.
- Closest median-AQI peer
- Charleston-North Charleston, SC (60.3% Good, median AQI 47) is the closest nationwide median-AQI peer to Riverton, WY.
- 2020–2025 Good-day shift
- Riverton, WY's Good-day share moved -8.5 points from 2020 to 2025 (median AQI +2).
- Median AQI
- Median AQI: 47
Aggregated from EPA Air Quality System (2025), 365 monitored days. EPA AQS →
The verdict
Riverton, WY's median AQI 47 is in the upper (dirtier) CBSA tercile on this site. On the EPA scale the metro runs good, more polluted than the median US metro, with a median AQI of 47 and 69.6% of 365 monitored days in the Good band.
- 47
- median AQI · Good
- 69.6%
- days rated Good
- 44%
- cleaner than US metros
- 100
- worst single reading
No day crossed into the Unhealthy tier across the metro's monitors in 2025.
Annual release change
What changed in the 2025 EPA annual release
- Riverton, WY metro's Good-day share rose from 58.2% to 69.6% between the 2024 and 2025 EPA annual releases, a change of +11.4 percentage points.
- Riverton, WY metro's peak single-day AQI fell from 139 to 100 between the 2024 and 2025 EPA annual releases, a change of -39 points.
Riverton, WY's median AQI 47 is in the upper (dirtier) CBSA tercile on this site. Signature read: median AQI 47 (high tercile vs CBSA corpus). Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 47 over 365 measured days in 2025 (Good / Moderate). The monitored-day split lands at 254 Good (70%), 111 Moderate (30%), and 0 Unhealthy-for-Sensitive-Groups (0%). The 90th-percentile AQI finished at 64; the highest single-day reading hit 100 (Moderate).
Across 2020–2025, Good-day share shifted -8.5 points and median AQI moved +2 (worsening). No Unhealthy-tier days appear in this annual dataset. Metros with comparable AQI profiles include Charleston-North Charleston, SC (60.3% good, AQI 47); Columbia, SC (58.1% good, AQI 47); Corsicana, TX (59.2% good, AQI 47).
Air Quality Summary
Median AQI
47
Good
Good Days
69.6%
254 of 365 days
Max AQI
100
Moderate
Health Grade
Moderate
90th pct: 64
AQI Day Breakdown (2025)
Distribution of 365 monitored days across EPA AQI categories.
Good
254
70%
Moderate
111
30%
USG
0
0%
Unhealthy
0
0%
Very Unhealthy
0
0%
Hazardous
0
0%
Health Impact Assessment
The Riverton, WY metro area's air quality is rated Moderate based on 69.6% good air days. No unhealthy air days were recorded in 2025.
Air quality is generally acceptable. Unusually sensitive people should monitor real-time conditions at AirNow.gov during high-pollution events.
How does the Riverton, WY metro compare?
How Riverton, WY compares
5-Year Air Quality Trend
Air quality is worsening in the Riverton, WY metro. Highest Good-day share: 2020 (78.1%, 282 of 361 monitored days).
| Year | Good | Moderate | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|
| 2020 | 282 | 78 | 1 | 45 | 161 |
| 2021 | 240 | 117 | 0 | 46 | 141 |
| 2022 | 254 | 111 | 0 | 46 | 100 |
| 2023 | 215 | 147 | 0 | 49 | 110 |
| 2024 | 210 | 151 | 0 | 49 | 139 |
| 2025 | 254 | 111 | 0 | 47 | 100 |
Metros with a similar median AQI
CBSA peers nationwide whose annual median AQI sits near Riverton, WY (47).
Charleston-North Charleston, SC
Median AQI 47 · 60.3% Good-day share
Columbia, SC
Median AQI 47 · 58.1% Good-day share
Corsicana, TX
Median AQI 47 · 59.2% Good-day share
Dayton, OH
Median AQI 47 · 57.0% Good-day share
Evansville, IN-KY
Median AQI 47 · 57.5% Good-day share
Farmington, NM
Median AQI 47 · 68.0% Good-day share
Metros with similar unhealthy-day exposure
A second relationship type: metros whose unhealthy-or-worse day count is closest to Riverton, WY's 0 (independent of median AQI).
Aberdeen, SD
0 unhealthy-or-worse days · median AQI 27
Aberdeen, WA
0 unhealthy-or-worse days · median AQI 22
Adrian, MI
0 unhealthy-or-worse days · median AQI 41
Akron, OH
0 unhealthy-or-worse days · median AQI 45
Albany, GA
0 unhealthy-or-worse days · median AQI 46
Albany, OR
0 unhealthy-or-worse days · median AQI 27
Frequently Asked Questions
What does AQI 47 mean for health? ▼
How many unhealthy air days does Riverton, WY have? ▼
What is the air quality in the Riverton, WY metro area? ▼
Is air quality in Riverton, WY getting better or worse? ▼
How does Riverton, WY compare to other metro areas? ▼
What is the 90th percentile AQI for Riverton, WY? ▼
Data Sources
Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset for Riverton, WY, 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, Riverton, WY · 2020–2025