Jacksonville Best & Worst AQI Days: Air Quality Guide
The worst air quality day on record for Jacksonville (Jacksonville, FL area) was December 12, 2025, when the daily AQI reached 155 (Unhealthy), set by fine particulate matter (PM2.5). Across 2,557 monitored days in 2019–2025, 1 of the 10 worst days was Unhealthy (AQI 151+) or worse; 7 of the 10 were driven by fine particulate matter (PM2.5) and 3 by ground-level ozone, and 6 of them fell in 2025. The cleanest day was September 1, 2019 at AQI 15 (Good); the 10 best days span 5 different years.
Improve Indoor Air Quality
Even with good outdoor air in Jacksonville, indoor PM2.5, dust and allergens build up. A True-HEPA purifier keeps a bedroom or office consistently clean.
Recommended: Levoit Core 400S — True HEPA · CADR ~141 CFM · rooms up to 219 sq ft
As an Amazon Associate, we earn from qualifying purchases.
When were Jacksonville's worst and best air quality days?
Worst: December 12, 2025, AQI 155 (Unhealthy, PM2.5). Best: September 1, 2019, AQI 15 (Good). Based on 2,557 EPA-monitored days in the Jacksonville, FL area, 2019–2025.
- ✓1 of the 10 worst days were Unhealthy (AQI 151+) or worse; the 10th-worst was AQI 105 (Unhealthy for Sensitive Groups).
- ✓Fine particulate matter (PM2.5) drove 7 of the 10 worst days.
- ✓2025 accounts for 6 of the 10 worst days.
Frequently asked questions
What was the worst air quality day in Jacksonville?▾
December 12, 2025: the Jacksonville, FL area's daily AQI hit 155 (Unhealthy), driven by fine particulate matter (PM2.5). That is the highest of 2,557 monitored days in 2019–2025.
What was the best air quality day in Jacksonville?▾
September 1, 2019, with a daily AQI of 15 (Good). The daily AQI is the highest reading from any monitor in the area, so even the cleanest day reflects the area's worst monitor.
What was Jacksonville's worst air quality day in 2025?▾
December 12, 2025, AQI 155 (Unhealthy), set by fine particulate matter (PM2.5).
Which pollutant causes Jacksonville's worst air days?▾
Fine particulate matter (PM2.5) set the AQI on 7 of the 10 worst days; ground-level ozone on 3. The tables above list the defining pollutant for every day.
Jacksonville's 10 worst air quality days, 2019–2025
Highest daily AQI recorded for the Jacksonville, FL area (EPA AQS). The daily AQI is the highest reading from any monitor in the area that day.
| # | Date | AQI | Category | Defining pollutant |
|---|---|---|---|---|
| 1 | (2025 page) | 155 | Unhealthy | PM2.5 — fine particulate matter (PM2.5) |
| 2 | (2020 page) | 140 | Unhealthy for Sensitive Groups | PM2.5 — fine particulate matter (PM2.5), in wildfire smoke season |
| 3 | (2025 page) | 136 | Unhealthy for Sensitive Groups | O3 — ground-level ozone |
| 4 | (2025 page) | 136 | Unhealthy for Sensitive Groups | O3 — ground-level ozone |
| 5 | (2023 page) | 124 | Unhealthy for Sensitive Groups | PM2.5 — fine particulate matter (PM2.5), in wildfire smoke season |
| 6 | (2020 page) | 119 | Unhealthy for Sensitive Groups | PM2.5 — fine particulate matter (PM2.5), in wildfire smoke season |
| 7 | (2025 page) | 117 | Unhealthy for Sensitive Groups | PM2.5 — fine particulate matter (PM2.5) |
| 8 | (2019 page) | 114 | Unhealthy for Sensitive Groups | PM2.5 — fine particulate matter (PM2.5), in wildfire smoke season |
| 9 | (2025 page) | 106 | Unhealthy for Sensitive Groups | PM2.5 — fine particulate matter (PM2.5) |
| 10 | (2025 page) | 105 | Unhealthy for Sensitive Groups | O3 — ground-level ozone |
Worst day of each year in Jacksonville
The single highest-AQI day in each year on record. Click a year for its full month-by-month statistics.
| Year | Worst day | AQI | Category | Defining pollutant |
|---|---|---|---|---|
| 2019 | 114 | Unhealthy for Sensitive Groups | PM2.5 — fine particulate matter (PM2.5), in wildfire smoke season | |
| 2020 | 140 | Unhealthy for Sensitive Groups | PM2.5 — fine particulate matter (PM2.5), in wildfire smoke season | |
| 2021 | 94 | Moderate | PM2.5 — fine particulate matter (PM2.5) | |
| 2022 | 93 | Moderate | O3 — ground-level ozone | |
| 2023 | 124 | Unhealthy for Sensitive Groups | PM2.5 — fine particulate matter (PM2.5), in wildfire smoke season | |
| 2024 | 98 | Moderate | PM2.5 — fine particulate matter (PM2.5) | |
| 2025 | 155 | Unhealthy | PM2.5 — fine particulate matter (PM2.5) |
Jacksonville's 10 best air quality days, 2019–2025
Lowest daily AQI recorded for the Jacksonville, FL area. Ties are listed most recent first.
| # | Date | AQI | Category | Defining pollutant |
|---|---|---|---|---|
| 1 | (2019 page) | 15 | Good | O3 — ground-level ozone |
| 2 | (2019 page) | 16 | Good | O3 — ground-level ozone |
| 3 | (2019 page) | 18 | Good | O3 — ground-level ozone |
| 4 | (2019 page) | 21 | Good | O3 — ground-level ozone, in peak ozone season |
| 5 | (2024 page) | 23 | Good | PM2.5 — fine particulate matter (PM2.5) |
| 6 | (2021 page) | 24 | Good | PM2.5 — fine particulate matter (PM2.5) |
| 7 | (2019 page) | 24 | Good | O3 — ground-level ozone |
| 8 | (2022 page) | 25 | Good | O3 — ground-level ozone |
| 9 | (2019 page) | 25 | Good | O3 — ground-level ozone |
| 10 | (2025 page) | 26 | Good | PM2.5 — fine particulate matter (PM2.5) |
Right now in Jacksonville
The latest EPA AirNow observation puts Jacksonville's AQI at 34 (PM2.5). The days above are historical records, not today's reading.
View current Jacksonville air quality →Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Jacksonville, 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.