Charlotte Air Quality in September
Across 2019–2025, Charlotte's September air quality had a median AQI of 51 (Moderate) over 210 monitored days in the Charlotte-Concord-Gastonia, NC-SC area. 2.4% of September days (5 of 210) reached Unhealthy for Sensitive Groups or worse, and ground-level ozone set the daily AQI on 52.9% of days. The cleanest September on record here was 2020 (median AQI 43, 0 days above 100) and the worst was 2019 (median 71, 5 days above 100, peak AQI 136).
- Good: 47.1%
- Moderate: 50.5%
- Unhealthy for Sensitive Groups: 2.4%
- Unhealthy or worse: 0.0%
Extra Protection for Charlotte Homes
Air quality in Charlotte is moderate (AQI 73), with fine particles (PM2.5) the main concern. A True-HEPA purifier gives sensitive groups — kids, seniors and anyone with asthma or allergies — cleaner air indoors on days like today.
Recommended: Coway AP-1512HH Mighty — True HEPA + carbon · CADR ~246 CFM · rooms up to 361 sq ft
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How is the air in Charlotte in September?
Moderate on a typical day: median AQI 51 across 2019–2025, with 2.4% of September days above AQI 100. Ground-level ozone is the main driver.
- ✓47.1% of September days were Good (AQI 0–50), 50.5% Moderate (51–100).
- ✓5 days of 210 reached AQI 101+; the September peak was 136.
- ✓Best September: 2020; worst September: 2019.
Frequently asked questions
What is the air quality like in Charlotte in September?▾
Across 2019–2025, the median daily AQI in Charlotte in September was 51 (Moderate). 47.1% of days were Good, 50.5% Moderate, and 2.4% reached Unhealthy for Sensitive Groups or worse, based on 210 monitored days in EPA's Air Quality System.
Is September a good time for outdoor exercise in Charlotte?▾
A typical September day in Charlotte is Moderate (median AQI 51): outdoor exercise is acceptable for most people, but unusually sensitive individuals should watch for symptoms, and about 1 day in 42 of September days (2.4%) reached AQI 101+ — the level at which EPA advises people with asthma, children and older adults to shorten hard outdoor exertion.
Which pollutant causes Charlotte's September air quality problems?▾
Ground-level ozone set the daily AQI on 52.9% of September days in Charlotte. The highest September AQI recorded in 2019–2025 was 136 (Unhealthy for Sensitive Groups), in 2019.
Charlotte September air quality, year by year
Charlotte September air quality by year (Charlotte-Concord-Gastonia, NC-SC, EPA AQS daily AQI)
| Year | Days monitored | Median AQI | Days above 100 | Peak AQI | Main pollutant |
|---|---|---|---|---|---|
| 2019worst | 30 | 71 | 5 | 136 | O3 |
| 2020cleanest | 30 | 43 | 0 | 69 | PM2.5 |
| 2021 | 30 | 53 | 0 | 74 | PM2.5 |
| 2022 | 30 | 47 | 0 | 100 | O3 |
| 2023 | 30 | 50 | 0 | 93 | O3 |
| 2024 | 30 | 46 | 0 | 74 | PM2.5 |
| 2025 | 30 | 54 | 0 | 80 | PM2.5 |
What September air means in Charlotte
A typical September day in Charlotte is Moderate (median AQI 51): outdoor exercise is acceptable for most people, but unusually sensitive individuals should watch for symptoms, and about 1 day in 42 of September days (2.4%) reached AQI 101+ — the level at which EPA advises people with asthma, children and older adults to shorten hard outdoor exertion.
September's median AQI of 51 is in line with Charlotte's whole-year median of 52, so this period is neither a clean nor a dirty stretch for the area. Nationally, the median September AQI across every EPA metro area (100,699 metro-days, 2019–2025) is 43, so Charlotte runs above the national September norm; 2.4% of its September days topped AQI 100 versus 2.7% nationally (about the same).
September is part of Charlotte's fall season (September, October, November); the fall page pools all three months.
Activity-specific thresholds: running, cycling, kids' sports.
Right now in Charlotte
The latest EPA AirNow observation puts Charlotte's AQI at 73 (PM2.5). The figures above are multi-year month statistics, not today's reading.
View current Charlotte air quality →Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Charlotte-Concord-Gastonia, NC-SC), 2019–2025. Daily AQI per CBSA is the highest AQI reported by any monitor in the area that day; the defining parameter is the pollutant that set it. Month and season statistics pool every such day in the period across all years listed. Retrieved 2026-09-09.