Fresno Air Quality in 2020

In 2020, Fresno's air quality (Fresno, CA area) had a median daily AQI of 76 (Moderate) across 366 monitored days. 99 days (27.0%) reached Unhealthy for Sensitive Groups or worse, 75 were Good, and the year's peak AQI was 346 (Hazardous). Fine particulate matter (PM2.5) set the daily AQI on 204 of those days. The cleanest month of 2020 was March (median AQI 42, 0 days above 100) and the worst was September (median 162, 22 days above 100, peak 346).

76
Median AQI
Moderate
99
Days above AQI 100
27.0% of 366 days
154
90th percentile AQI
worst 1 day in 10
346
Peak AQI
Hazardous
PM2.5
Main pollutant
204 of 366 days
75
Good days
20.5% of days
  • Good: 20.5%
  • Moderate: 52.5%
  • Unhealthy for Sensitive Groups: 16.1%
  • Unhealthy or worse: 10.9%

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QUICK ANSWER

How was Fresno's air quality in 2020?

Moderate on a typical day: median AQI 76, with 99 days above AQI 100 out of 366 monitored — the 7th cleanest of 7 years on record for the area.

  • Peak AQI in 2020: 346 (Hazardous).
  • Fine particulate matter (PM2.5) was the main pollutant on 204 days.
  • Cleanest month: March; worst: September.

Frequently asked questions

What was the average AQI in Fresno in 2020?

EPA's Air Quality System puts Fresno's (Fresno, CA) median daily AQI for 2020 at 76, which is Moderate. 99 days were Unhealthy for Sensitive Groups or worse and the year's highest AQI was 346.

Which month had the worst air quality in Fresno in 2020?

The cleanest month of 2020 was March (median AQI 42, 0 days above 100) and the worst was September (median 162, 22 days above 100, peak 346).

Was 2020 a good or bad year for Fresno's air?

Among the 7 years EPA has published for the area (2019–2025), 2020 ranks 7th cleanest by days above AQI 100 — the worst year on record here. 2020's median of 76 is above the area's typical annual median of 67.

Fresno month by month in 2020

Fresno air quality month by month, 2020 (Fresno, CA, EPA AQS daily AQI)

MonthDays monitoredMedian AQIDays above 100Peak AQIMain pollutant
January31703130PM2.5
February2967092PM2.5
Marchcleanest3142072O3
April3047077O3
May31545143O3
June30577150O3
July31906119O3
August3110818254O3
Septemberworst3016222346PM2.5
October3113219207PM2.5
November30899155PM2.5
December319110126PM2.5

How 2020 compares

Among the 7 years EPA has published for the area (2019–2025), 2020 ranks 7th cleanest by days above AQI 100 — the worst year on record here.

2020's median of 76 is above the area's typical annual median of 67.

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

Right now in Fresno

The latest EPA AirNow observation puts Fresno's AQI at 49 (PM2.5). The figures above are multi-year annual statistics, not today's reading.

View current Fresno air quality →

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