Louisville Air Quality in August
Across 2019–2025, Louisville's August air quality had a median AQI of 54 (Moderate) over 217 monitored days in the Louisville/Jefferson County, KY-IN area. 5.5% of August days (12 of 217) reached Unhealthy for Sensitive Groups or worse, and fine particulate matter (PM2.5) set the daily AQI on 53.0% of days. The cleanest August on record here was 2022 (median AQI 53, 0 days above 100) and the worst was 2024 (median 56, 6 days above 100, peak AQI 150).
- Good: 34.1%
- Moderate: 60.4%
- Unhealthy for Sensitive Groups: 5.5%
- Unhealthy or worse: 0.0%
Extra Protection for Louisville Homes
Air quality in Louisville is moderate (AQI 61), 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
As an Amazon Associate, we earn from qualifying purchases.
How is the air in Louisville in August?
Moderate on a typical day: median AQI 54 across 2019–2025, with 5.5% of August days above AQI 100. Fine particulate matter (PM2.5) is the main driver.
- ✓34.1% of August days were Good (AQI 0–50), 60.4% Moderate (51–100).
- ✓12 days of 217 reached AQI 101+; the August peak was 150.
- ✓Best August: 2022; worst August: 2024.
Frequently asked questions
What is the air quality like in Louisville in August?▾
Across 2019–2025, the median daily AQI in Louisville in August was 54 (Moderate). 34.1% of days were Good, 60.4% Moderate, and 5.5% reached Unhealthy for Sensitive Groups or worse, based on 217 monitored days in EPA's Air Quality System.
Is August a good time for outdoor exercise in Louisville?▾
A typical August day in Louisville is Moderate (median AQI 54): outdoor exercise is acceptable for most people, but unusually sensitive individuals should watch for symptoms, and about 1 day in 18 of August days (5.5%) reached AQI 101+ — the level at which EPA advises people with asthma, children and older adults to shorten hard outdoor exertion.
Which pollutant causes Louisville's August air quality problems?▾
Fine particulate matter (PM2.5) set the daily AQI on 53.0% of August days in Louisville. The highest August AQI recorded in 2019–2025 was 150 (Unhealthy for Sensitive Groups), in 2024.
Louisville August air quality, year by year
Louisville August air quality by year (Louisville/Jefferson County, KY-IN, EPA AQS daily AQI)
| Year | Days monitored | Median AQI | Days above 100 | Peak AQI | Main pollutant |
|---|---|---|---|---|---|
| 2019 | 31 | 54 | 1 | 136 | O3 |
| 2020 | 31 | 52 | 1 | 115 | PM2.5 |
| 2021 | 31 | 58 | 1 | 105 | PM2.5 |
| 2022cleanest | 31 | 53 | 0 | 97 | PM2.5 |
| 2023 | 31 | 58 | 3 | 150 | PM2.5 |
| 2024worst | 31 | 56 | 6 | 150 | O3 |
| 2025 | 31 | 53 | 0 | 90 | O3 |
What August air means in Louisville
A typical August day in Louisville is Moderate (median AQI 54): outdoor exercise is acceptable for most people, but unusually sensitive individuals should watch for symptoms, and about 1 day in 18 of August days (5.5%) reached AQI 101+ — the level at which EPA advises people with asthma, children and older adults to shorten hard outdoor exertion.
August's median AQI of 54 is in line with Louisville's whole-year median of 54, so this period is neither a clean nor a dirty stretch for the area. Nationally, the median August AQI across every EPA metro area (104,152 metro-days, 2019–2025) is 45, so Louisville runs above the national August norm; 5.5% of its August days topped AQI 100 versus 3.5% nationally (above average).
August is part of Louisville's summer season (June, July, August); the summer page pools all three months.
Activity-specific thresholds: running, cycling, kids' sports.
Right now in Louisville
The latest EPA AirNow observation puts Louisville's AQI at 61 (PM2.5). The figures above are multi-year month statistics, not today's reading.
View current Louisville air quality →Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Louisville/Jefferson County, KY-IN), 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.