Springfield, IL Air Quality in Summer
Across 2019–2025, Springfield's summer (June–August) air quality had a median AQI of 49 (Good) over 644 monitored days in the Springfield, IL area. 3.5% of summer days (22 of 644) reached Unhealthy for Sensitive Groups or worse, and fine particulate matter (PM2.5) set the daily AQI on 56.4% of days. The cleanest summer on record here was 2019 (median AQI 45, 0 days above 100) and the worst was 2023 (median 61, 14 days above 100, peak AQI 247).
- Good: 52.3%
- Moderate: 44.3%
- Unhealthy for Sensitive Groups: 3.0%
- Unhealthy or worse: 0.5%
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 summer?
Good on a typical day: median AQI 49 across 2019–2025, with 3.5% of summer days above AQI 100. Fine particulate matter (PM2.5) is the main driver.
- ✓52.3% of summer days were Good (AQI 0–50), 44.3% Moderate (51–100).
- ✓22 days of 644 reached AQI 101+; the summer peak was 247.
- ✓Cleanest month: August; worst month: June.
Frequently asked questions
What is the air quality like in Springfield in summer?▾
Across 2019–2025, the median daily AQI in Springfield in summer was 49 (Good). 52.3% of days were Good, 44.3% Moderate, and 3.5% 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 Springfield?▾
A typical summer day in Springfield sits in the Good range (median AQI 49), so running, cycling and children's outdoor play are fine for everyone on most days; about 1 day in 29 of summer days (3.5%) reached AQI 101+ in 2019–2025.
Which pollutant causes Springfield's summer air quality problems?▾
Fine particulate matter (PM2.5) set the daily AQI on 56.4% of summer days in Springfield. The highest summer AQI recorded in 2019–2025 was 247 (Very Unhealthy), in 2023.
Springfield summer air quality, year by year
Springfield summer air quality by year (Springfield, IL, EPA AQS daily AQI)
| Year | Days monitored | Median AQI | Days above 100 | Peak AQI | Main pollutant |
|---|---|---|---|---|---|
| 2019cleanest | 92 | 45 | 0 | 87 | O3 |
| 2020 | 92 | 48 | 0 | 97 | O3 |
| 2021 | 92 | 50 | 0 | 98 | PM2.5 |
| 2022 | 92 | 48 | 4 | 126 | PM2.5 |
| 2023worst | 92 | 61 | 14 | 247 | PM2.5 |
| 2024 | 92 | 50 | 1 | 105 | PM2.5 |
| 2025 | 92 | 48 | 3 | 142 | PM2.5 |
What summer air means in Springfield
A typical summer day in Springfield sits in the Good range (median AQI 49), so running, cycling and children's outdoor play are fine for everyone on most days; about 1 day in 29 of summer days (3.5%) reached AQI 101+ in 2019–2025.
Summer's median AQI of 49 is above Springfield's whole-year median of 44, 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 Springfield runs in line with the national Summer norm; 3.5% of its Summer days topped AQI 100 versus 3.6% nationally (about the same).
Within the season, August is the cleanest month (median AQI 46, 0.5% of days above 100) and June the worst (median 51, 9.0% above 100).
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 season 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.