Los Angeles Air Quality in 2020
In 2020, Los Angeles's air quality (Los Angeles-Long Beach-Anaheim, CA area) had a median daily AQI of 85 (Moderate) across 366 monitored days. 142 days (38.8%) reached Unhealthy for Sensitive Groups or worse, 35 were Good, and the year's peak AQI was 250 (Very Unhealthy). Ground-level ozone set the daily AQI on 181 of those days. The cleanest month of 2020 was March (median AQI 47, 0 days above 100) and the worst was September (median 161, 28 days above 100, peak 235).
- Good: 9.6%
- Moderate: 51.6%
- Unhealthy for Sensitive Groups: 21.6%
- Unhealthy or worse: 17.2%
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How was Los Angeles's air quality in 2020?
Moderate on a typical day: median AQI 85, with 142 days above AQI 100 out of 366 monitored — the 7th cleanest of 7 years on record for the area.
- ✓Peak AQI in 2020: 250 (Very Unhealthy).
- ✓Ground-level ozone was the main pollutant on 181 days.
- ✓Cleanest month: March; worst: September.
Frequently asked questions
What was the average AQI in Los Angeles in 2020?▾
EPA's Air Quality System puts Los Angeles's (Los Angeles-Long Beach-Anaheim, CA) median daily AQI for 2020 at 85, which is Moderate. 142 days were Unhealthy for Sensitive Groups or worse and the year's highest AQI was 250.
Which month had the worst air quality in Los Angeles in 2020?▾
The cleanest month of 2020 was March (median AQI 47, 0 days above 100) and the worst was September (median 161, 28 days above 100, peak 235).
Was 2020 a good or bad year for Los Angeles's air?▾
Among the 7 years EPA has published for the area (2019–2025), 2020 ranks 7th cleanest by days above AQI 100 — the worst year on record here. 2020's median of 85 is above the area's typical annual median of 74.
Los Angeles month by month in 2020
Los Angeles air quality month by month, 2020 (Los Angeles-Long Beach-Anaheim, CA, EPA AQS daily AQI)
| Month | Days monitored | Median AQI | Days above 100 | Peak AQI | Main pollutant |
|---|---|---|---|---|---|
| January | 31 | 73 | 5 | 130 | PM2.5 |
| February | 29 | 66 | 0 | 85 | PM2.5 |
| Marchcleanest | 31 | 47 | 0 | 75 | PM2.5 |
| April | 30 | 56 | 8 | 185 | O3 |
| May | 31 | 90 | 12 | 206 | O3 |
| June | 30 | 80 | 13 | 161 | O3 |
| July | 31 | 129 | 24 | 250 | O3 |
| August | 31 | 122 | 23 | 222 | O3 |
| Septemberworst | 30 | 161 | 28 | 235 | O3 |
| October | 31 | 129 | 21 | 210 | O3 |
| November | 30 | 79 | 3 | 114 | PM2.5 |
| December | 31 | 83 | 5 | 120 | PM2.5 |
How 2020 compares
Among the 7 years EPA has published for the area (2019–2025), 2020 ranks 7th cleanest by days above AQI 100 — the worst year on record here.
2020's median of 85 is above the area's typical annual median of 74.
Activity-specific thresholds: running, cycling, kids' sports.
Right now in Los Angeles
The latest EPA AirNow observation puts Los Angeles's AQI at 41 (PM2.5). The figures above are multi-year annual statistics, not today's reading.
View current Los Angeles air quality →Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Los Angeles-Long Beach-Anaheim, CA), 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.