Springfield, IL Air Quality in August
Across 2019–2025, Springfield's August air quality had a median AQI of 46 (Good) over 217 monitored days in the Springfield, IL area. 0.5% of August days (1 of 217) reached Unhealthy for Sensitive Groups or worse, and fine particulate matter (PM2.5) set the daily AQI on 67.7% of days. The cleanest August on record here was 2019 (median AQI 39, 0 days above 100) and the worst was 2025 (median 46, 1 day above 100, peak AQI 142).
- Good: 60.8%
- Moderate: 38.7%
- Unhealthy for Sensitive Groups: 0.5%
- Unhealthy or worse: 0.0%
Reduce Indoor Ozone in Springfield
Today's main pollutant in Springfield is ground-level ozone (AQI 32). Important: standard HEPA filters do NOT remove ozone — only a purifier with a substantial activated-carbon bed adsorbs it. The biggest wins are cutting indoor sources (gas appliances, certain "ionizer" purifiers) and ventilating when outdoor ozone is low (early morning). A high-carbon unit helps with the gases and VOCs that linger indoors.
Recommended: Levoit Core 300 — True HEPA + activated carbon · CADR ~141 CFM · rooms up to 219 sq ft
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How is the air in Springfield in August?
Good on a typical day: median AQI 46 across 2019–2025, with 0.5% of August days above AQI 100. Fine particulate matter (PM2.5) is the main driver.
- ✓60.8% of August days were Good (AQI 0–50), 38.7% Moderate (51–100).
- ✓1 day of 217 reached AQI 101+; the August peak was 142.
- ✓Best August: 2019; worst August: 2025.
Frequently asked questions
What is the air quality like in Springfield in August?▾
Across 2019–2025, the median daily AQI in Springfield in August was 46 (Good). 60.8% of days were Good, 38.7% Moderate, and 0.5% 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 Springfield?▾
A typical August day in Springfield sits in the Good range (median AQI 46), so running, cycling and children's outdoor play are fine for everyone on most days; fewer than 1% of August days reached AQI 101+ in 2019–2025.
Which pollutant causes Springfield's August air quality problems?▾
Fine particulate matter (PM2.5) set the daily AQI on 67.7% of August days in Springfield. The highest August AQI recorded in 2019–2025 was 142 (Unhealthy for Sensitive Groups), in 2025.
Springfield August air quality, year by year
Springfield August air quality by year (Springfield, IL, EPA AQS daily AQI)
| Year | Days monitored | Median AQI | Days above 100 | Peak AQI | Main pollutant |
|---|---|---|---|---|---|
| 2019cleanest | 31 | 39 | 0 | 61 | O3 |
| 2020 | 31 | 43 | 0 | 58 | O3 |
| 2021 | 31 | 53 | 0 | 82 | PM2.5 |
| 2022 | 31 | 42 | 0 | 53 | PM2.5 |
| 2023 | 31 | 55 | 0 | 77 | PM2.5 |
| 2024 | 31 | 52 | 0 | 65 | PM2.5 |
| 2025worst | 31 | 46 | 1 | 142 | PM2.5 |
What August air means in Springfield
A typical August day in Springfield sits in the Good range (median AQI 46), so running, cycling and children's outdoor play are fine for everyone on most days; fewer than 1% of August days reached AQI 101+ in 2019–2025.
August's median AQI of 46 is in line with Springfield's whole-year median of 44, 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 Springfield runs in line with the national August norm; 0.5% of its August days topped AQI 100 versus 3.5% nationally (below average).
August is part of Springfield's summer season (June, July, August); the summer page pools all three months.
Activity-specific thresholds: running, cycling, kids' sports.
Right now in Springfield
The latest EPA AirNow observation puts Springfield's AQI at 32 (O3). The figures above are multi-year month statistics, not today's reading.
View current Springfield air quality →Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Springfield, IL), 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.