Indianapolis Air Quality in Summer
Across 2019–2025, Indianapolis's summer (June–August) air quality had a median AQI of 60 (Moderate) over 644 monitored days in the Indianapolis-Carmel-Anderson, IN area. 6.0% of summer days (39 of 644) reached Unhealthy for Sensitive Groups or worse, and fine particulate matter (PM2.5) set the daily AQI on 65.5% of days. The cleanest summer on record here was 2021 (median AQI 61, 2 days above 100) and the worst was 2023 (median 69, 17 days above 100, peak AQI 259).
- Good: 20.3%
- Moderate: 73.6%
- Unhealthy for Sensitive Groups: 5.1%
- Unhealthy or worse: 0.9%
Extra Protection for Indianapolis Homes
Air quality in Indianapolis is moderate (AQI 55), 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 Indianapolis in summer?
Moderate on a typical day: median AQI 60 across 2019–2025, with 6.0% of summer days above AQI 100. Fine particulate matter (PM2.5) is the main driver.
- ✓20.3% of summer days were Good (AQI 0–50), 73.6% Moderate (51–100).
- ✓39 days of 644 reached AQI 101+; the summer peak was 259.
- ✓Cleanest month: August; worst month: June.
Frequently asked questions
What is the air quality like in Indianapolis in summer?▾
Across 2019–2025, the median daily AQI in Indianapolis in summer was 60 (Moderate). 20.3% of days were Good, 73.6% Moderate, and 6.0% reached Unhealthy for Sensitive Groups or worse, based on 644 monitored days in EPA's Air Quality System.
Is summer a good time for outdoor exercise in Indianapolis?▾
A typical summer day in Indianapolis is Moderate (median AQI 60): outdoor exercise is acceptable for most people, but unusually sensitive individuals should watch for symptoms, and about 1 day in 17 of summer days (6.0%) reached AQI 101+ — the level at which EPA advises people with asthma, children and older adults to shorten hard outdoor exertion.
Which pollutant causes Indianapolis's summer air quality problems?▾
Fine particulate matter (PM2.5) set the daily AQI on 65.5% of summer days in Indianapolis. The highest summer AQI recorded in 2019–2025 was 259 (Very Unhealthy), in 2023.
Indianapolis summer air quality, year by year
Indianapolis summer air quality by year (Indianapolis-Carmel-Anderson, IN, EPA AQS daily AQI)
| Year | Days monitored | Median AQI | Days above 100 | Peak AQI | Main pollutant |
|---|---|---|---|---|---|
| 2019 | 92 | 60 | 3 | 112 | PM2.5 |
| 2020 | 92 | 57 | 4 | 115 | PM2.5 |
| 2021cleanest | 92 | 61 | 2 | 112 | PM2.5 |
| 2022 | 92 | 58 | 7 | 133 | PM2.5 |
| 2023worst | 92 | 69 | 17 | 259 | PM2.5 |
| 2024 | 92 | 58 | 3 | 116 | PM2.5 |
| 2025 | 92 | 57 | 3 | 170 | PM2.5 |
What summer air means in Indianapolis
A typical summer day in Indianapolis is Moderate (median AQI 60): outdoor exercise is acceptable for most people, but unusually sensitive individuals should watch for symptoms, and about 1 day in 17 of summer days (6.0%) reached AQI 101+ — the level at which EPA advises people with asthma, children and older adults to shorten hard outdoor exertion.
Summer's median AQI of 60 is above Indianapolis's whole-year median of 56, making it one of the area's dirtier periods. Nationally, the median Summer AQI across every EPA metro area (308,645 metro-days, 2019–2025) is 46, so Indianapolis runs above the national Summer norm; 6.0% of its Summer days topped AQI 100 versus 3.6% nationally (above average).
Within the season, August is the cleanest month (median AQI 57, 1.9% of days above 100) and June the worst (median 64, 10.4% above 100).
Activity-specific thresholds: running, cycling, kids' sports.
Right now in Indianapolis
The latest EPA AirNow observation puts Indianapolis's AQI at 55 (PM2.5). The figures above are multi-year season statistics, not today's reading.
View current Indianapolis air quality →Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Indianapolis-Carmel-Anderson, 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.