Charleston, SC Air Quality in 2020
In 2020, Charleston's air quality (Charleston-North Charleston, SC area) had a median daily AQI of 43 (Good) across 366 monitored days. 1 day (0.3%) reached Unhealthy for Sensitive Groups or worse, 264 were Good, and the year's peak AQI was 117 (Unhealthy for Sensitive Groups). Fine particulate matter (PM2.5) set the daily AQI on 296 of those days. The cleanest month of 2020 was January (median AQI 38, 0 days above 100) and the worst was June (median 38, 1 day above 100, peak 117).
- Good: 72.1%
- Moderate: 27.6%
- Unhealthy for Sensitive Groups: 0.3%
- Unhealthy or worse: 0.0%
Improve Indoor Air Quality
Even with good outdoor air in Charleston, 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.
How was Charleston's air quality in 2020?
Good on a typical day: median AQI 43, with 1 day above AQI 100 out of 366 monitored — the 5th cleanest of 7 years on record for the area.
- ✓Peak AQI in 2020: 117 (Unhealthy for Sensitive Groups).
- ✓Fine particulate matter (PM2.5) was the main pollutant on 296 days.
- ✓Cleanest month: January; worst: June.
Frequently asked questions
What was the average AQI in Charleston in 2020?▾
EPA's Air Quality System puts Charleston's (Charleston-North Charleston, SC) median daily AQI for 2020 at 43, which is Good. 1 day were Unhealthy for Sensitive Groups or worse and the year's highest AQI was 117.
Which month had the worst air quality in Charleston in 2020?▾
The cleanest month of 2020 was January (median AQI 38, 0 days above 100) and the worst was June (median 38, 1 day above 100, peak 117).
Was 2020 a good or bad year for Charleston's air?▾
Among the 7 years EPA has published for the area (2019–2025), 2020 ranks 5th cleanest by days above AQI 100. 2020's median of 43 is below the area's typical annual median of 47.
Charleston month by month in 2020
Charleston air quality month by month, 2020 (Charleston-North Charleston, SC, EPA AQS daily AQI)
| Month | Days monitored | Median AQI | Days above 100 | Peak AQI | Main pollutant |
|---|---|---|---|---|---|
| Januarycleanest | 31 | 38 | 0 | 58 | PM2.5 |
| February | 29 | 41 | 0 | 58 | O3 |
| March | 31 | 48 | 0 | 61 | PM2.5 |
| April | 30 | 44 | 0 | 61 | O3 |
| May | 31 | 42 | 0 | 58 | PM2.5 |
| Juneworst | 30 | 38 | 1 | 117 | PM2.5 |
| July | 31 | 47 | 0 | 68 | PM2.5 |
| August | 31 | 43 | 0 | 65 | PM2.5 |
| September | 30 | 43 | 0 | 74 | PM2.5 |
| October | 31 | 41 | 0 | 63 | PM2.5 |
| November | 30 | 43 | 0 | 66 | PM2.5 |
| December | 31 | 51 | 0 | 82 | PM2.5 |
How 2020 compares
Among the 7 years EPA has published for the area (2019–2025), 2020 ranks 5th cleanest by days above AQI 100.
2020's median of 43 is below the area's typical annual median of 47.
Activity-specific thresholds: running, cycling, kids' sports.
Right now in Charleston
The latest EPA AirNow observation puts Charleston's AQI at 19 (PM2.5). The figures above are multi-year annual statistics, not today's reading.
View current Charleston air quality →Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Charleston-North Charleston, 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.