Modesto Air Quality in 2024
In 2024, Modesto's air quality (Modesto, CA area) had a median daily AQI of 53 (Moderate) across 366 monitored days. 38 days (10.4%) reached Unhealthy for Sensitive Groups or worse, 166 were Good, and the year's peak AQI was 150 (Unhealthy for Sensitive Groups). Ground-level ozone set the daily AQI on 214 of those days. The cleanest month of 2024 was February (median AQI 38, 0 days above 100) and the worst was July (median 93, 15 days above 100, peak 147).
- Good: 45.4%
- Moderate: 44.3%
- Unhealthy for Sensitive Groups: 10.4%
- Unhealthy or worse: 0.0%
Extra Protection for Modesto Homes
Air quality in Modesto is moderate (AQI 63), with particle pollution 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
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How was Modesto's air quality in 2024?
Moderate on a typical day: median AQI 53, with 38 days above AQI 100 out of 366 monitored — the 6th cleanest of 7 years on record for the area.
- ✓Peak AQI in 2024: 150 (Unhealthy for Sensitive Groups).
- ✓Ground-level ozone was the main pollutant on 214 days.
- ✓Cleanest month: February; worst: July.
Frequently asked questions
What was the average AQI in Modesto in 2024?▾
EPA's Air Quality System puts Modesto's (Modesto, CA) median daily AQI for 2024 at 53, which is Moderate. 38 days were Unhealthy for Sensitive Groups or worse and the year's highest AQI was 150.
Which month had the worst air quality in Modesto in 2024?▾
The cleanest month of 2024 was February (median AQI 38, 0 days above 100) and the worst was July (median 93, 15 days above 100, peak 147).
Was 2024 a good or bad year for Modesto's air?▾
Among the 7 years EPA has published for the area (2019–2025), 2024 ranks 6th cleanest by days above AQI 100. 2024's median of 53 is in line with the area's typical annual median of 54.
Modesto month by month in 2024
Modesto air quality month by month, 2024 (Modesto, CA, EPA AQS daily AQI)
| Month | Days monitored | Median AQI | Days above 100 | Peak AQI | Main pollutant |
|---|---|---|---|---|---|
| January | 31 | 55 | 0 | 81 | PM2.5 |
| Februarycleanest | 29 | 38 | 0 | 65 | PM2.5 |
| March | 31 | 39 | 0 | 54 | O3 |
| April | 30 | 46 | 0 | 71 | O3 |
| May | 31 | 50 | 0 | 87 | O3 |
| June | 30 | 66 | 4 | 143 | O3 |
| Julyworst | 31 | 93 | 15 | 147 | O3 |
| August | 31 | 67 | 6 | 140 | O3 |
| September | 30 | 56 | 3 | 136 | O3 |
| October | 31 | 52 | 3 | 150 | O3 |
| November | 30 | 50 | 0 | 89 | PM2.5 |
| December | 31 | 68 | 7 | 141 | PM2.5 |
How 2024 compares
Among the 7 years EPA has published for the area (2019–2025), 2024 ranks 6th cleanest by days above AQI 100.
2024's median of 53 is in line with the area's typical annual median of 54.
Activity-specific thresholds: running, cycling, kids' sports.
Right now in Modesto
The latest EPA AirNow observation puts Modesto's AQI at 63 (PM10). The figures above are multi-year annual statistics, not today's reading.
View current Modesto air quality →Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Modesto, CA), 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.