St. Petersburg Air Quality in September
Across 2019–2025, St. Petersburg's September air quality had a median AQI of 46 (Good) over 210 monitored days in the Tampa-St. Petersburg-Clearwater, FL area. 0.0% of September days (0 of 210) reached Unhealthy for Sensitive Groups or worse, and fine particulate matter (PM2.5) set the daily AQI on 59.5% of days. The cleanest September on record here was 2022 (median AQI 40, 0 days above 100) and the worst was 2021 (median 52, 0 days above 100, peak AQI 77).
- Good: 64.3%
- Moderate: 35.7%
- Unhealthy for Sensitive Groups: 0.0%
- Unhealthy or worse: 0.0%
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How is the air in St. Petersburg in September?
Good on a typical day: median AQI 46 across 2019–2025, with 0.0% of September days above AQI 100. Fine particulate matter (PM2.5) is the main driver.
- ✓64.3% of September days were Good (AQI 0–50), 35.7% Moderate (51–100).
- ✓0 days of 210 reached AQI 101+; the September peak was 93.
- ✓Best September: 2022; worst September: 2021.
Frequently asked questions
What is the air quality like in St. Petersburg in September?▾
Across 2019–2025, the median daily AQI in St. Petersburg in September was 46 (Good). 64.3% of days were Good, 35.7% Moderate, and 0.0% reached Unhealthy for Sensitive Groups or worse, based on 210 monitored days in EPA's Air Quality System.
Is September a good time for outdoor exercise in St. Petersburg?▾
A typical September day in St. Petersburg sits in the Good range (median AQI 46), so running, cycling and children's outdoor play are fine for everyone on most days; fewer than 1% of September days reached AQI 101+ in 2019–2025.
Which pollutant causes St. Petersburg's September air quality problems?▾
Fine particulate matter (PM2.5) set the daily AQI on 59.5% of September days in St. Petersburg. The highest September AQI recorded in 2019–2025 was 93 (Moderate), in 2021.
St. Petersburg September air quality, year by year
St. Petersburg September 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 | 30 | 48 | 0 | 93 | PM2.5 |
| 2020 | 30 | 45 | 0 | 77 | PM2.5 |
| 2021worst | 30 | 52 | 0 | 77 | PM2.5 |
| 2022cleanest | 30 | 40 | 0 | 73 | PM2.5 |
| 2023 | 30 | 50 | 0 | 90 | O3 |
| 2024 | 30 | 44 | 0 | 58 | PM2.5 |
| 2025 | 30 | 44 | 0 | 77 | O3 |
What September air means in St. Petersburg
A typical September day in St. Petersburg sits in the Good range (median AQI 46), so running, cycling and children's outdoor play are fine for everyone on most days; fewer than 1% of September days reached AQI 101+ in 2019–2025.
September's median AQI of 46 is below St. Petersburg's whole-year median of 51, making it one of the area's cleaner periods. Nationally, the median September AQI across every EPA metro area (100,699 metro-days, 2019–2025) is 43, so St. Petersburg runs in line with the national September norm; 0.0% of its September days topped AQI 100 versus 2.7% nationally (below average).
September is part of St. Petersburg's fall season (September, October, November); the fall page pools all three months.
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 month 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.