Metro area air quality · 2025
Wilmington, OH
Median AQI 41 (Good). 83.1% of monitored days rated Good across this metro's EPA monitoring network.
- 41
- Median AQI
- 83.1%
- Good-air days
- 0
- Unhealthy days
- 73%
- Cleaner than US metros
Wilmington, OH posted a 2025 median AQI of 41 (Good) with 83.1% Good days
According to the U.S. EPA Air Quality System, the Wilmington, OH CBSA recorded a median AQI of 41 across 243 monitored days in 2025, with 83.1% 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 Wilmington, OH CBSA's 83.1% Good-day share places it cleaner than 73% of US metros in 2025.
- Closest median-AQI peer
- Adrian, MI (69.3% Good, median AQI 41) is the closest nationwide median-AQI peer to Wilmington, OH.
- 2020–2025 Good-day shift
- Wilmington, OH's Good-day share moved -5.4 points from 2020 to 2025 (median AQI +2).
- Median AQI
- Median AQI: 41
Aggregated from EPA Air Quality System (2025), 243 monitored days. EPA AQS →
The verdict
Wilmington, OH sits in the upper Good-day tercile among EPA CBSA metros on this site (83.1% of 243 monitored days). On the EPA scale the metro runs good, cleaner than the median US metro, with a median AQI of 41 and 83.1% of 243 monitored days in the Good band.
- 41
- median AQI · Good
- 83.1%
- days rated Good
- 73%
- cleaner than US metros
- 112
- 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
- Wilmington, OH metro's Good-day share rose from 74.6% to 84.2% between the 2024 and 2025 EPA annual releases, a change of +9.6 percentage points.
- Wilmington, OH metro's median AQI fell from 44 to 41 between the 2024 and 2025 EPA annual releases, a change of -3 points.
Wilmington, OH sits in the upper Good-day tercile among EPA CBSA metros on this site (83.1% of 243 monitored days). Signature read: 83.1% 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 41 over 243 measured days in 2025 (Good / Good). The monitored-day split lands at 202 Good (83%), 38 Moderate (16%), and 3 Unhealthy-for-Sensitive-Groups (1%). The 90th-percentile AQI finished at 61; the highest single-day reading hit 112 (USG).
Across 2020–2025, Good-day share shifted -5.4 points and median AQI moved +2 (worsening). No Unhealthy-tier days appear in this annual dataset. Metros with comparable AQI profiles include Adrian, MI (69.3% good, AQI 41); Albany-Schenectady-Troy, NY (67.7% good, AQI 41); Ann Arbor, MI (69.3% good, AQI 41).
Air Quality Summary
Median AQI
41
Good
Good Days
83.1%
202 of 243 days
Max AQI
112
USG
Health Grade
Good
90th pct: 61
AQI Day Breakdown (2025)
Distribution of 243 monitored days across EPA AQI categories.
Good
202
83%
Moderate
38
16%
USG
3
1%
Unhealthy
0
0%
Very Unhealthy
0
0%
Hazardous
0
0%
Health Impact Assessment
The Wilmington, OH metro area's air quality is rated Good based on 83.1% 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 Wilmington, OH metro compare?
How Wilmington, OH compares
5-Year Air Quality Trend
Air quality is worsening in the Wilmington, OH metro. Highest Good-day share: 2020 (89.5%, 205 of 229 monitored days).
| Year | Good | Moderate | Unhealthy | Median AQI | Max AQI |
|---|---|---|---|---|---|
| 2020 | 205 | 24 | 0 | 39 | 97 |
| 2021 | 209 | 31 | 0 | 39 | 84 |
| 2022 | 216 | 28 | 0 | 40 | 140 |
| 2023 | 199 | 39 | 0 | 44 | 129 |
| 2024 | 176 | 60 | 0 | 44 | 112 |
| 2025 | 202 | 38 | 0 | 41 | 112 |
Metros with a similar median AQI
CBSA peers nationwide whose annual median AQI sits near Wilmington, OH (41).
Adrian, MI
Median AQI 41 · 69.3% Good-day share
Albany-Schenectady-Troy, NY
Median AQI 41 · 67.7% Good-day share
Ann Arbor, MI
Median AQI 41 · 69.3% Good-day share
Bowling Green, KY
Median AQI 41 · 75.6% Good-day share
Brunswick, GA
Median AQI 41 · 74.3% Good-day share
Decatur, AL
Median AQI 41 · 78.4% Good-day share
Metros with similar unhealthy-day exposure
A second relationship type: metros whose unhealthy-or-worse day count is closest to Wilmington, OH'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
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
Alexandria, LA
0 unhealthy-or-worse days · median AQI 37
Frequently Asked Questions
How many unhealthy air days does Wilmington, OH have? ▼
What is the air quality in the Wilmington, OH metro area? ▼
Is air quality in Wilmington, OH getting better or worse? ▼
What does AQI 41 mean for health? ▼
How does Wilmington, OH compare to other metro areas? ▼
What is the 90th percentile AQI for Wilmington, OH? ▼
Data Sources
Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by CBSA dataset for Wilmington, OH, 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, Wilmington, OH · 2020–2025