Metro area air quality · 2025
Rock Springs, WY
Median AQI 44 (Good). 72.9% of monitored days rated Good across this metro's EPA monitoring network.
- 44
- Median AQI
- 72.9%
- Good-air days
- 0
- Unhealthy days
- 51%
- Cleaner than US metros
Rock Springs, WY posted a 2025 median AQI of 44 (Good) with 72.9% Good days
According to the U.S. EPA Air Quality System, the Rock Springs, WY CBSA recorded a median AQI of 44 across 365 monitored days in 2025, with 72.9% 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 Rock Springs, WY CBSA's 72.9% Good-day share places it cleaner than 51% of US metros in 2025.
- Closest median-AQI peer
- Bartlesville, OK (68.0% Good, median AQI 44) is the closest nationwide median-AQI peer to Rock Springs, WY.
- 2020–2025 Good-day shift
- Rock Springs, WY's Good-day share moved +8.9 points from 2020 to 2025 (median AQI -2).
- Median AQI
- Median AQI: 44
Aggregated from EPA Air Quality System (2025), 365 monitored days. EPA AQS →
The verdict
Rock Springs, WY's Good-day share (72.9%) sits in the middle CBSA tercile on this extract. On the EPA scale the metro runs good, cleaner than the median US metro, with a median AQI of 44 and 72.9% of 365 monitored days in the Good band.
- 44
- median AQI · Good
- 72.9%
- days rated Good
- 51%
- cleaner than US metros
- 118
- 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
- Rock Springs, WY metro's Good-day share rose from 69.4% to 74.5% between the 2024 and 2025 EPA annual releases, a change of +5.1 percentage points.
- Rock Springs, WY metro's peak single-day AQI fell from 137 to 118 between the 2024 and 2025 EPA annual releases, a change of -19 points.
Rock Springs, WY's Good-day share (72.9%) sits in the middle CBSA tercile on this extract. Signature read: 72.9% Good-day share (mid tercile vs CBSA corpus). Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 44 over 365 measured days in 2025 (Good / Moderate). The monitored-day split lands at 266 Good (73%), 91 Moderate (25%), and 8 Unhealthy-for-Sensitive-Groups (2%). The 90th-percentile AQI finished at 64; the highest single-day reading hit 118 (USG).
Across 2020–2025, Good-day share shifted +8.9 points and median AQI moved -2 (improving). No Unhealthy-tier days appear in this annual dataset. Metros with comparable AQI profiles include Bartlesville, OK (68.0% good, AQI 44); Berlin, NH-VT (81.5% good, AQI 44); Bloomington, IL (66.0% good, AQI 44).
Air Quality Summary
Median AQI
44
Good
Good Days
72.9%
266 of 365 days
Max AQI
118
USG
Health Grade
Moderate
90th pct: 64
AQI Day Breakdown (2025)
Distribution of 365 monitored days across EPA AQI categories.
Good
266
73%
Moderate
91
25%
USG
8
2%
Unhealthy
0
0%
Very Unhealthy
0
0%
Hazardous
0
0%
Health Impact Assessment
The Rock Springs, WY metro area's air quality is rated Moderate based on 72.9% 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 Rock Springs, WY metro compare?
How Rock Springs, WY compares
5-Year Air Quality Trend
Air quality is improving in the Rock Springs, WY metro. Highest Good-day share: 2022 (78.3%, 285 of 364 monitored days).
| Year | Good | Moderate | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|
| 2020 | 235 | 119 | 4 | 46 | 1334 |
| 2021 | 238 | 117 | 1 | 45 | 195 |
| 2022 | 285 | 78 | 1 | 44 | 157 |
| 2023 | 253 | 103 | 0 | 47 | 211 |
| 2024 | 247 | 109 | 0 | 45 | 137 |
| 2025 | 266 | 91 | 0 | 44 | 118 |
Metros with a similar median AQI
CBSA peers nationwide whose annual median AQI sits near Rock Springs, WY (44).
Bartlesville, OK
Median AQI 44 · 68.0% Good-day share
Berlin, NH-VT
Median AQI 44 · 81.5% Good-day share
Bloomington, IL
Median AQI 44 · 66.0% Good-day share
Boston-Cambridge-Newton, MA-NH
Median AQI 44 · 71.0% Good-day share
Bridgeport-Stamford-Norwalk, CT
Median AQI 44 · 64.7% Good-day share
Buffalo-Cheektowaga-Niagara Falls, NY
Median AQI 44 · 63.8% Good-day share
Metros with similar unhealthy-day exposure
A second relationship type: metros whose unhealthy-or-worse day count is closest to Rock Springs, 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
How many unhealthy air days does Rock Springs, WY have? ▼
What is the air quality in the Rock Springs, WY metro area? ▼
Is air quality in Rock Springs, WY getting better or worse? ▼
What does AQI 44 mean for health? ▼
How does Rock Springs, WY compare to other metro areas? ▼
What is the 90th percentile AQI for Rock Springs, WY? ▼
Data Sources
Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset for Rock Springs, 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, Rock Springs, WY · 2020–2025