Columbia Best & Worst AQI Days: Air Quality Guide
The worst air quality day on record for Columbia (Columbia, SC area) was March 14, 2024, when the daily AQI reached 141 (Unhealthy for Sensitive Groups), set by fine particulate matter (PM2.5). Across 2,557 monitored days in 2019–2025, 0 of the 10 worst days were Unhealthy (AQI 151+) or worse; 6 of the 10 were driven by fine particulate matter (PM2.5) and 4 by ground-level ozone, and 5 of them fell in 2023. The cleanest day was February 23, 2019 at AQI 8 (Good); the 10 best days span 3 different years.
Extra Protection for Columbia Homes
Air quality in Columbia is moderate (AQI 52), 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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When were Columbia's worst and best air quality days?
Worst: March 14, 2024, AQI 141 (Unhealthy for Sensitive Groups, PM2.5). Best: February 23, 2019, AQI 8 (Good). Based on 2,557 EPA-monitored days in the Columbia, SC area, 2019–2025.
- ✓0 of the 10 worst days were Unhealthy (AQI 151+) or worse; the 10th-worst was AQI 97 (Moderate).
- ✓Fine particulate matter (PM2.5) drove 6 of the 10 worst days.
- ✓2023 accounts for 5 of the 10 worst days.
Frequently asked questions
What was the worst air quality day in Columbia?▾
March 14, 2024: the Columbia, SC area's daily AQI hit 141 (Unhealthy for Sensitive Groups), 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 Columbia?▾
February 23, 2019, with a daily AQI of 8 (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 Columbia's worst air quality day in 2025?▾
December 17, 2025, AQI 89 (Moderate), set by fine particulate matter (PM2.5).
Which pollutant causes Columbia's worst air days?▾
Fine particulate matter (PM2.5) set the AQI on 6 of the 10 worst days; ground-level ozone on 4. The tables above list the defining pollutant for every day.
Columbia's 10 worst air quality days, 2019–2025
Highest daily AQI recorded for the Columbia, SC area (EPA AQS). The daily AQI is the highest reading from any monitor in the area that day.
| # | Date | AQI | Category | Defining pollutant |
|---|---|---|---|---|
| 1 | (2024 page) | 141 | Unhealthy for Sensitive Groups | PM2.5 — fine particulate matter (PM2.5) |
| 2 | (2023 page) | 123 | Unhealthy for Sensitive Groups | PM2.5 — fine particulate matter (PM2.5) |
| 3 | (2020 page) | 117 | Unhealthy for Sensitive Groups | PM2.5 — fine particulate matter (PM2.5), in wildfire smoke season |
| 4 | (2023 page) | 113 | Unhealthy for Sensitive Groups | PM2.5 — fine particulate matter (PM2.5), in wildfire smoke season |
| 5 | (2023 page) | 108 | Unhealthy for Sensitive Groups | O3 — ground-level ozone, in peak ozone season |
| 6 | (2021 page) | 102 | Unhealthy for Sensitive Groups | PM2.5 — fine particulate matter (PM2.5), in wildfire smoke season |
| 7 | (2023 page) | 101 | Unhealthy for Sensitive Groups | O3 — ground-level ozone, in peak ozone season |
| 8 | (2021 page) | 101 | Unhealthy for Sensitive Groups | O3 — ground-level ozone, in peak ozone season |
| 9 | (2024 page) | 97 | Moderate | PM2.5 — fine particulate matter (PM2.5) |
| 10 | (2023 page) | 97 | Moderate | O3 — ground-level ozone, in peak ozone season |
Worst day of each year in Columbia
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 | 93 | Moderate | O3 — ground-level ozone | |
| 2020 | 117 | Unhealthy for Sensitive Groups | PM2.5 — fine particulate matter (PM2.5), in wildfire smoke season | |
| 2021 | 102 | Unhealthy for Sensitive Groups | PM2.5 — fine particulate matter (PM2.5), in wildfire smoke season | |
| 2022 | 93 | Moderate | O3 — ground-level ozone | |
| 2023 | 123 | Unhealthy for Sensitive Groups | PM2.5 — fine particulate matter (PM2.5) | |
| 2024 | 141 | Unhealthy for Sensitive Groups | PM2.5 — fine particulate matter (PM2.5) | |
| 2025 | 89 | Moderate | PM2.5 — fine particulate matter (PM2.5) |
Columbia's 10 best air quality days, 2019–2025
Lowest daily AQI recorded for the Columbia, SC area. Ties are listed most recent first.
| # | Date | AQI | Category | Defining pollutant |
|---|---|---|---|---|
| 1 | (2019 page) | 8 | Good | PM2.5 — fine particulate matter (PM2.5) |
| 2 | (2019 page) | 11 | Good | PM2.5 — fine particulate matter (PM2.5) |
| 3 | (2019 page) | 11 | Good | PM2.5 — fine particulate matter (PM2.5) |
| 4 | (2019 page) | 12 | Good | PM2.5 — fine particulate matter (PM2.5) |
| 5 | (2019 page) | 15 | Good | PM2.5 — fine particulate matter (PM2.5) |
| 6 | (2020 page) | 16 | Good | PM2.5 — fine particulate matter (PM2.5) |
| 7 | (2020 page) | 16 | Good | PM2.5 — fine particulate matter (PM2.5) |
| 8 | (2023 page) | 17 | Good | PM2.5 — fine particulate matter (PM2.5) |
| 9 | (2020 page) | 17 | Good | PM2.5 — fine particulate matter (PM2.5) |
| 10 | (2019 page) | 17 | Good | PM2.5 — fine particulate matter (PM2.5) |
Right now in Columbia
The latest EPA AirNow observation puts Columbia's AQI at 52 (PM2.5). The days above are historical records, not today's reading.
View current Columbia air quality →Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Columbia, SC), 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.