Charleston, SC Air Quality in 2019

In 2019, Charleston's air quality (Charleston-North Charleston, SC area) had a median daily AQI of 42 (Good) across 357 monitored days. 0 days (0.0%) reached Unhealthy for Sensitive Groups or worse, 262 were Good, and the year's peak AQI was 76 (Moderate). Fine particulate matter (PM2.5) set the daily AQI on 313 of those days. The cleanest month of 2019 was December (median AQI 33, 0 days above 100) and the worst was March (median 48, 0 days above 100, peak 60).

42
Median AQI
Good
0
Days above AQI 100
0.0% of 357 days
56
90th percentile AQI
worst 1 day in 10
76
Peak AQI
Moderate
PM2.5
Main pollutant
313 of 357 days
262
Good days
73.4% of days
  • Good: 73.4%
  • Moderate: 26.6%
  • Unhealthy for Sensitive Groups: 0.0%
  • Unhealthy or worse: 0.0%

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QUICK ANSWER

How was Charleston's air quality in 2019?

Good on a typical day: median AQI 42, with 0 days above AQI 100 out of 357 monitored — the 1st cleanest of 7 years on record for the area.

  • Peak AQI in 2019: 76 (Moderate).
  • Fine particulate matter (PM2.5) was the main pollutant on 313 days.
  • Cleanest month: December; worst: March.

Frequently asked questions

What was the average AQI in Charleston in 2019?

EPA's Air Quality System puts Charleston's (Charleston-North Charleston, SC) median daily AQI for 2019 at 42, which is Good. 0 days were Unhealthy for Sensitive Groups or worse and the year's highest AQI was 76.

Which month had the worst air quality in Charleston in 2019?

The cleanest month of 2019 was December (median AQI 33, 0 days above 100) and the worst was March (median 48, 0 days above 100, peak 60).

Was 2019 a good or bad year for Charleston's air?

Among the 7 years EPA has published for the area (2019–2025), 2019 ranks 1st cleanest by days above AQI 100 — the best year on record here. 2019's median of 42 is below the area's typical annual median of 47.

Charleston month by month in 2019

Charleston air quality month by month, 2019 (Charleston-North Charleston, SC, EPA AQS daily AQI)

MonthDays monitoredMedian AQIDays above 100Peak AQIMain pollutant
January3142066PM2.5
February2844057PM2.5
Marchworst3148060PM2.5
April3043062PM2.5
May3144066PM2.5
June3043075PM2.5
July3144076PM2.5
August3141065PM2.5
September2240067PM2.5
October3137055PM2.5
November3041063PM2.5
Decembercleanest3133055PM2.5

How 2019 compares

Among the 7 years EPA has published for the area (2019–2025), 2019 ranks 1st cleanest by days above AQI 100 — the best year on record here.

2019's median of 42 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.