Visalia Air Quality in Fall
Across 2019–2025, Visalia's fall (September–November) air quality had a median AQI of 83 (Moderate) over 637 monitored days in the Visalia-Porterville, CA area. 33.9% of fall days (216 of 637) reached Unhealthy for Sensitive Groups or worse, and fine particulate matter (PM2.5) set the daily AQI on 50.4% of days. The cleanest fall on record here was 2025 (median AQI 66, 6 days above 100) and the worst was 2020 (median 108, 51 days above 100, peak AQI 192).
- Good: 10.8%
- Moderate: 55.3%
- Unhealthy for Sensitive Groups: 24.3%
- Unhealthy or worse: 9.6%
Extra Protection for Visalia Homes
Air quality in Visalia is moderate (AQI 66), with fine particles (PM2.5) 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 is the air in Visalia in fall?
Moderate on a typical day: median AQI 83 across 2019–2025, with 33.9% of fall days above AQI 100. Fine particulate matter (PM2.5) is the main driver.
- ✓10.8% of fall days were Good (AQI 0–50), 55.3% Moderate (51–100).
- ✓216 days of 637 reached AQI 101+; the fall peak was 961.
- ✓Cleanest month: November; worst month: September.
Frequently asked questions
What is the air quality like in Visalia in fall?▾
Across 2019–2025, the median daily AQI in Visalia in fall was 83 (Moderate). 10.8% of days were Good, 55.3% Moderate, and 33.9% 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 Visalia?▾
A typical fall day in Visalia is Moderate (median AQI 83): outdoor exercise is acceptable for most people, but unusually sensitive individuals should watch for symptoms, and about 1 day in 3 of fall days (33.9%) reached AQI 101+ — the level at which EPA advises people with asthma, children and older adults to shorten hard outdoor exertion.
Which pollutant causes Visalia's fall air quality problems?▾
Fine particulate matter (PM2.5) set the daily AQI on 50.4% of fall days in Visalia. The highest fall AQI recorded in 2019–2025 was 961 (Hazardous), in 2020.
Visalia fall air quality, year by year
Visalia fall air quality by year (Visalia-Porterville, CA, EPA AQS daily AQI)
| Year | Days monitored | Median AQI | Days above 100 | Peak AQI | Main pollutant |
|---|---|---|---|---|---|
| 2019 | 91 | 84 | 25 | 280 | O3 |
| 2020worst | 91 | 108 | 51 | 192 | PM2.5 |
| 2021 | 91 | 97 | 44 | 961 | PM2.5 |
| 2022 | 91 | 90 | 38 | 182 | O3 |
| 2023 | 91 | 77 | 22 | 242 | PM2.5 |
| 2024 | 91 | 77 | 30 | 174 | O3 |
| 2025cleanest | 91 | 66 | 6 | 129 | PM2.5 |
What fall air means in Visalia
A typical fall day in Visalia is Moderate (median AQI 83): outdoor exercise is acceptable for most people, but unusually sensitive individuals should watch for symptoms, and about 1 day in 3 of fall days (33.9%) 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 83 is above Visalia's whole-year median of 71, making it one of the area's dirtier periods. Nationally, the median Fall AQI across every EPA metro area (296,275 metro-days, 2019–2025) is 40, so Visalia runs above the national Fall norm; 33.9% of its Fall days topped AQI 100 versus 1.5% nationally (above average).
Within the season, November is the cleanest month (median AQI 74, 13.8% of days above 100) and September the worst (median 107, 55.7% above 100).
Activity-specific thresholds: running, cycling, kids' sports.
Right now in Visalia
The latest EPA AirNow observation puts Visalia's AQI at 66 (PM2.5). The figures above are multi-year season statistics, not today's reading.
View current Visalia air quality →Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Visalia-Porterville, 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.