Rockford Air Quality in 2023

In 2023, Rockford's air quality (Rockford, IL area) had a median daily AQI of 52 (Moderate) across 365 monitored days. 20 days (5.5%) reached Unhealthy for Sensitive Groups or worse, 167 were Good, and the year's peak AQI was 242 (Very Unhealthy). Fine particulate matter (PM2.5) set the daily AQI on 265 of those days. The cleanest month of 2023 was February (median AQI 39, 0 days above 100) and the worst was June (median 99, 14 days above 100, peak 242).

52
Median AQI
Moderate
20
Days above AQI 100
5.5% of 365 days
77
90th percentile AQI
worst 1 day in 10
242
Peak AQI
Very Unhealthy
PM2.5
Main pollutant
265 of 365 days
167
Good days
45.8% of days
  • Good: 45.8%
  • Moderate: 48.8%
  • Unhealthy for Sensitive Groups: 4.7%
  • Unhealthy or worse: 0.8%

Improve Indoor Air Quality

Even with good outdoor air in Rockford, indoor PM2.5, dust and allergens build up. A True-HEPA purifier keeps a bedroom or office consistently clean.

Recommended: Levoit Core 400STrue HEPA · CADR ~141 CFM · rooms up to 219 sq ft

Check Price on Amazon →

As an Amazon Associate, we earn from qualifying purchases.

QUICK ANSWER

How was Rockford's air quality in 2023?

Moderate on a typical day: median AQI 52, with 20 days above AQI 100 out of 365 monitored — the 7th cleanest of 7 years on record for the area.

  • Peak AQI in 2023: 242 (Very Unhealthy).
  • Fine particulate matter (PM2.5) was the main pollutant on 265 days.
  • Cleanest month: February; worst: June.

Frequently asked questions

What was the average AQI in Rockford in 2023?

EPA's Air Quality System puts Rockford's (Rockford, IL) median daily AQI for 2023 at 52, which is Moderate. 20 days were Unhealthy for Sensitive Groups or worse and the year's highest AQI was 242.

Which month had the worst air quality in Rockford in 2023?

The cleanest month of 2023 was February (median AQI 39, 0 days above 100) and the worst was June (median 99, 14 days above 100, peak 242).

Was 2023 a good or bad year for Rockford's air?

Among the 7 years EPA has published for the area (2019–2025), 2023 ranks 7th cleanest by days above AQI 100 — the worst year on record here. 2023's median of 52 is above the area's typical annual median of 47.

Rockford month by month in 2023

Rockford air quality month by month, 2023 (Rockford, IL, EPA AQS daily AQI)

MonthDays monitoredMedian AQIDays above 100Peak AQIMain pollutant
January3152077PM2.5
Februarycleanest2839072PM2.5
March3149071PM2.5
April3046067O3
May31593133O3
Juneworst309914242PM2.5
July31533123O3
August3158072PM2.5
September3052071PM2.5
October3142068PM2.5
November3049083PM2.5
December3142068PM2.5

How 2023 compares

Among the 7 years EPA has published for the area (2019–2025), 2023 ranks 7th cleanest by days above AQI 100 — the worst year on record here.

2023's median of 52 is above the area's typical annual median of 47.

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

Right now in Rockford

The latest EPA AirNow observation puts Rockford's AQI at 30 (PM2.5). The figures above are multi-year annual statistics, not today's reading.

View current Rockford air quality →

Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Rockford, 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.