Springfield, IL Air Quality in 2019

In 2019, Springfield's air quality (Springfield, IL area) had a median daily AQI of 45 (Good) across 360 monitored days. 0 days (0.0%) reached Unhealthy for Sensitive Groups or worse, 222 were Good, and the year's peak AQI was 87 (Moderate). Fine particulate matter (PM2.5) set the daily AQI on 238 of those days. The cleanest month of 2019 was October (median AQI 32, 0 days above 100) and the worst was January (median 53, 0 days above 100, peak 70).

45
Median AQI
Good
0
Days above AQI 100
0.0% of 360 days
61
90th percentile AQI
worst 1 day in 10
87
Peak AQI
Moderate
PM2.5
Main pollutant
238 of 360 days
222
Good days
61.7% of days
  • Good: 61.7%
  • Moderate: 38.3%
  • Unhealthy for Sensitive Groups: 0.0%
  • Unhealthy or worse: 0.0%

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QUICK ANSWER

How was Springfield's air quality in 2019?

Good on a typical day: median AQI 45, with 0 days above AQI 100 out of 360 monitored — the 3rd cleanest of 7 years on record for the area.

  • Peak AQI in 2019: 87 (Moderate).
  • Fine particulate matter (PM2.5) was the main pollutant on 238 days.
  • Cleanest month: October; worst: January.

Frequently asked questions

What was the average AQI in Springfield in 2019?

EPA's Air Quality System puts Springfield's (Springfield, IL) median daily AQI for 2019 at 45, which is Good. 0 days were Unhealthy for Sensitive Groups or worse and the year's highest AQI was 87.

Which month had the worst air quality in Springfield in 2019?

The cleanest month of 2019 was October (median AQI 32, 0 days above 100) and the worst was January (median 53, 0 days above 100, peak 70).

Was 2019 a good or bad year for Springfield's air?

Among the 7 years EPA has published for the area (2019–2025), 2019 ranks 3rd cleanest by days above AQI 100. 2019's median of 45 is in line with the area's typical annual median of 44.

Springfield month by month in 2019

Springfield air quality month by month, 2019 (Springfield, IL, EPA AQS daily AQI)

MonthDays monitoredMedian AQIDays above 100Peak AQIMain pollutant
Januaryworst2753070PM2.5
February2850066PM2.5
March3146069O3
April3047077O3
May3145077O3
June3048087O3
July3151075PM2.5
August3139061O3
September3048061PM2.5
Octobercleanest3132054PM2.5
November2936075PM2.5
December3152072PM2.5

How 2019 compares

Among the 7 years EPA has published for the area (2019–2025), 2019 ranks 3rd cleanest by days above AQI 100.

2019's median of 45 is in line with the area's typical annual median of 44.

Activity-specific thresholds: running, cycling, kids' sports.

Right now in Springfield

The latest EPA AirNow observation puts Springfield's AQI at 25 (PM2.5). The figures above are multi-year annual 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.