Metro area air quality · 2025
Twin Falls, ID
Median AQI 26 (Good). 92.9% of monitored days rated Good across this metro's EPA monitoring network.
- 26
- Median AQI
- 92.9%
- Good-air days
- 0
- Unhealthy days
- 90%
- Cleaner than US metros
Twin Falls, ID posted a 2025 median AQI of 26 (Good) with 92.9% Good days
According to the U.S. EPA Air Quality System, the Twin Falls, ID CBSA recorded a median AQI of 26 across 365 monitored days in 2025, with 92.9% 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 Twin Falls, ID CBSA's 92.9% Good-day share places it cleaner than 90% of US metros in 2025.
- Closest median-AQI peer
- Pahrump, NV (92.6% Good, median AQI 26) is the closest nationwide median-AQI peer to Twin Falls, ID.
- 2020–2025 Good-day shift
- Twin Falls, ID's Good-day share moved +6.4 points from 2020 to 2025 (median AQI +2).
- Median AQI
- Median AQI: 26
Aggregated from EPA Air Quality System (2025), 365 monitored days. EPA AQS →
The verdict
Twin Falls, ID sits in the upper Good-day tercile among EPA CBSA metros on this site (92.9% of 365 monitored days). On the EPA scale the metro runs good, among the cleanest 10% of US metros, with a median AQI of 26 and 92.9% of 365 monitored days in the Good band.
- 26
- median AQI · Good
- 92.9%
- days rated Good
- 90%
- cleaner than US metros
- 105
- 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
- Twin Falls, ID metro's Good-day share rose from 77.0% to 93.1% between the 2024 and 2025 EPA annual releases, a change of +16.2 percentage points.
- Twin Falls, ID metro's peak single-day AQI fell from 158 to 105 between the 2024 and 2025 EPA annual releases, a change of -53 points.
- Twin Falls, ID metro's Unhealthy-category days fell from 3 to 0 between the 2024 and 2025 EPA annual releases, a change of -3 days.
- Twin Falls, ID metro's median AQI rose from 23 to 26 between the 2024 and 2025 EPA annual releases, a change of +3 points.
Twin Falls, ID sits in the upper Good-day tercile among EPA CBSA metros on this site (92.9% of 365 monitored days). Signature read: 92.9% Good-day share (high tercile vs CBSA corpus). Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 26 over 365 measured days in 2025 (Good / Excellent). The monitored-day split lands at 339 Good (93%), 25 Moderate (7%), and 1 Unhealthy-for-Sensitive-Groups (0%). The 90th-percentile AQI finished at 47; the highest single-day reading hit 105 (USG).
Across 2020–2025, Good-day share shifted +6.4 points and median AQI moved +2 (improving). No Unhealthy-tier days appear in this annual dataset. Metros with comparable AQI profiles include Pahrump, NV (92.6% good, AQI 26); Aberdeen, SD (83.6% good, AQI 27); Albany, OR (80.0% good, AQI 27).
Air Quality Summary
Median AQI
26
Good
Good Days
92.9%
339 of 365 days
Max AQI
105
USG
Health Grade
Excellent
90th pct: 47
AQI Day Breakdown (2025)
Distribution of 365 monitored days across EPA AQI categories.
Good
339
93%
Moderate
25
7%
USG
1
0%
Unhealthy
0
0%
Very Unhealthy
0
0%
Hazardous
0
0%
Health Impact Assessment
The Twin Falls, ID metro area's air quality is rated Excellent based on 92.9% 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 Twin Falls, ID metro compare?
How Twin Falls, ID compares
5-Year Air Quality Trend
Air quality is improving in the Twin Falls, ID metro. Highest Good-day share: 2023 (95.3%, 328 of 344 monitored days).
| Year | Good | Moderate | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|
| 2020 | 315 | 44 | 4 | 24 | 163 |
| 2021 | 298 | 56 | 0 | 28 | 144 |
| 2022 | 280 | 71 | 1 | 31 | 155 |
| 2023 | 328 | 16 | 0 | 25 | 80 |
| 2024 | 264 | 76 | 3 | 23 | 158 |
| 2025 | 339 | 25 | 0 | 26 | 105 |
Metros with a similar median AQI
CBSA peers nationwide whose annual median AQI sits near Twin Falls, ID (26).
Pahrump, NV
Median AQI 26 · 92.6% Good-day share
Aberdeen, SD
Median AQI 27 · 83.6% Good-day share
Albany, OR
Median AQI 27 · 80.0% Good-day share
Anchorage, AK
Median AQI 27 · 77.5% Good-day share
Ellensburg, WA
Median AQI 25 · 80.0% Good-day share
La Grande, OR
Median AQI 27 · 84.4% Good-day share
Metros with similar unhealthy-day exposure
A second relationship type: metros whose unhealthy-or-worse day count is closest to Twin Falls, ID's 0 (independent of median AQI).
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-Schenectady-Troy, NY
0 unhealthy-or-worse days · median AQI 41
Alexandria, LA
0 unhealthy-or-worse days · median AQI 37
Frequently Asked Questions
How many unhealthy air days does Twin Falls, ID have? ▼
What is the air quality in the Twin Falls, ID metro area? ▼
Is air quality in Twin Falls, ID getting better or worse? ▼
What does AQI 26 mean for health? ▼
How does Twin Falls, ID compare to other metro areas? ▼
What is the 90th percentile AQI for Twin Falls, ID? ▼
Data Sources
Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset for Twin Falls, ID, 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, Twin Falls, ID · 2020–2025