Sacramento Air Quality in Fall

Across 2019–2025, Sacramento's fall (September–November) air quality had a median AQI of 61 (Moderate) over 637 monitored days in the Sacramento--Roseville--Arden-Arcade, CA area. 11.2% of fall days (71 of 637) reached Unhealthy for Sensitive Groups or worse, and fine particulate matter (PM2.5) set the daily AQI on 57.3% of days. The cleanest fall on record here was 2025 (median AQI 53, 1 day above 100) and the worst was 2020 (median 80, 29 days above 100, peak AQI 243).

61
Median AQI
Moderate
11.2%
Days above AQI 100
71 of 637 days
105
90th percentile AQI
worst 1 day in 10
442
Peak AQI
Hazardous
PM2.5
Main pollutant
57.3% of days
24.5%
Good days
156 of 637
  • Good: 24.5%
  • Moderate: 64.4%
  • Unhealthy for Sensitive Groups: 7.1%
  • Unhealthy or worse: 4.1%

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QUICK ANSWER

How is the air in Sacramento in fall?

Moderate on a typical day: median AQI 61 across 2019–2025, with 11.2% of fall days above AQI 100. Fine particulate matter (PM2.5) is the main driver.

  • 24.5% of fall days were Good (AQI 0–50), 64.4% Moderate (51–100).
  • 71 days of 637 reached AQI 101+; the fall peak was 442.
  • Cleanest month: November; worst month: September.

Frequently asked questions

What is the air quality like in Sacramento in fall?

Across 2019–2025, the median daily AQI in Sacramento in fall was 61 (Moderate). 24.5% of days were Good, 64.4% Moderate, and 11.2% reached Unhealthy for Sensitive Groups or worse, based on 637 monitored days in EPA's Air Quality System.

Is fall a good time for outdoor exercise in Sacramento?

A typical fall day in Sacramento is Moderate (median AQI 61): outdoor exercise is acceptable for most people, but unusually sensitive individuals should watch for symptoms, and about 1 day in 9 of fall days (11.2%) reached AQI 101+ — the level at which EPA advises people with asthma, children and older adults to shorten hard outdoor exertion.

Which pollutant causes Sacramento's fall air quality problems?

Fine particulate matter (PM2.5) set the daily AQI on 57.3% of fall days in Sacramento. The highest fall AQI recorded in 2019–2025 was 442 (Hazardous), in 2020.

Sacramento fall air quality, year by year

Sacramento fall air quality by year (Sacramento--Roseville--Arden-Arcade, CA, EPA AQS daily AQI)

YearDays monitoredMedian AQIDays above 100Peak AQIMain pollutant
201991625136O3
2020worst918029243PM2.5
2021916914151PM2.5
2022916616442PM2.5
202391581107PM2.5
202491555133PM2.5
2025cleanest91531119PM2.5

What fall air means in Sacramento

A typical fall day in Sacramento is Moderate (median AQI 61): outdoor exercise is acceptable for most people, but unusually sensitive individuals should watch for symptoms, and about 1 day in 9 of fall days (11.2%) reached AQI 101+ — the level at which EPA advises people with asthma, children and older adults to shorten hard outdoor exertion.

Fall's median AQI of 61 is in line with Sacramento's whole-year median of 58, so this period is neither a clean nor a dirty stretch for the area. Nationally, the median Fall AQI across every EPA metro area (296,275 metro-days, 2019–2025) is 40, so Sacramento runs above the national Fall norm; 11.2% of its Fall days topped AQI 100 versus 1.5% nationally (above average).

Within the season, November is the cleanest month (median AQI 61, 2.4% of days above 100) and September the worst (median 74, 25.8% above 100).

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

Right now in Sacramento

The latest EPA AirNow observation puts Sacramento's AQI at 43 (PM2.5). The figures above are multi-year season statistics, not today's reading.

View current Sacramento air quality →

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