St. Petersburg Air Quality in Fall
Across 2019–2025, St. Petersburg's fall (September–November) air quality had a median AQI of 47 (Good) over 633 monitored days in the Tampa-St. Petersburg-Clearwater, FL area. 0.3% of fall days (2 of 633) reached Unhealthy for Sensitive Groups or worse, and fine particulate matter (PM2.5) set the daily AQI on 66.2% of days. The cleanest fall on record here was 2020 (median AQI 46, 0 days above 100) and the worst was 2023 (median 51, 1 day above 100, peak AQI 114).
- Good: 60.3%
- Moderate: 39.3%
- Unhealthy for Sensitive Groups: 0.3%
- Unhealthy or worse: 0.0%
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How is the air in St. Petersburg in fall?
Good on a typical day: median AQI 47 across 2019–2025, with 0.3% of fall days above AQI 100. Fine particulate matter (PM2.5) is the main driver.
- ✓60.3% of fall days were Good (AQI 0–50), 39.3% Moderate (51–100).
- ✓2 days of 633 reached AQI 101+; the fall peak was 114.
- ✓Cleanest month: September; worst month: October.
Frequently asked questions
What is the air quality like in St. Petersburg in fall?▾
Across 2019–2025, the median daily AQI in St. Petersburg in fall was 47 (Good). 60.3% of days were Good, 39.3% Moderate, and 0.3% reached Unhealthy for Sensitive Groups or worse, based on 633 monitored days in EPA's Air Quality System.
Is fall a good time for outdoor exercise in St. Petersburg?▾
A typical fall day in St. Petersburg sits in the Good range (median AQI 47), so running, cycling and children's outdoor play are fine for everyone on most days; fewer than 1% of fall days reached AQI 101+ in 2019–2025.
Which pollutant causes St. Petersburg's fall air quality problems?▾
Fine particulate matter (PM2.5) set the daily AQI on 66.2% of fall days in St. Petersburg. The highest fall AQI recorded in 2019–2025 was 114 (Unhealthy for Sensitive Groups), in 2023.
St. Petersburg fall air quality, year by year
St. Petersburg fall air quality by year (Tampa-St. Petersburg-Clearwater, FL, EPA AQS daily AQI)
| Year | Days monitored | Median AQI | Days above 100 | Peak AQI | Main pollutant |
|---|---|---|---|---|---|
| 2019 | 91 | 48 | 0 | 93 | PM2.5 |
| 2020cleanest | 91 | 46 | 0 | 77 | PM2.5 |
| 2021 | 91 | 48 | 0 | 77 | PM2.5 |
| 2022 | 91 | 48 | 0 | 90 | PM2.5 |
| 2023worst | 91 | 51 | 1 | 114 | PM2.5 |
| 2024 | 87 | 46 | 1 | 105 | PM2.5 |
| 2025 | 91 | 46 | 0 | 87 | O3 |
What fall air means in St. Petersburg
A typical fall day in St. Petersburg sits in the Good range (median AQI 47), so running, cycling and children's outdoor play are fine for everyone on most days; fewer than 1% of fall days reached AQI 101+ in 2019–2025.
Fall's median AQI of 47 is below St. Petersburg's whole-year median of 51, making it one of the area's cleaner periods. Nationally, the median Fall AQI across every EPA metro area (296,275 metro-days, 2019–2025) is 40, so St. Petersburg runs above the national Fall norm; 0.3% of its Fall days topped AQI 100 versus 1.5% nationally (below average).
Within the season, September is the cleanest month (median AQI 46, 0.0% of days above 100) and October the worst (median 47, 0.9% above 100).
Activity-specific thresholds: running, cycling, kids' sports.
Right now in St. Petersburg
The latest EPA AirNow observation puts St. Petersburg's AQI at 38 (PM2.5). The figures above are multi-year season statistics, not today's reading.
View current St. Petersburg air quality →Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Tampa-St. Petersburg-Clearwater, FL), 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.