San Diego, California Air Quality
San Diego County, California (CA)
→ Stableover 10 years
10-Year AQI Trend
The solid line shows the median AQI each year. The dashed line shows the 90th percentile (worst 10% of days).
Air Quality Day Breakdown
Number of days per year in each EPA AQI category. Green = Good (AQI 0-50), Yellow = Moderate (51-100), Orange = Unhealthy for Sensitive Groups (101-150), Red = Unhealthy or worse (151+).
Year-by-Year Data
| Year | Median AQI | 90th Pct | Max AQI | Good Days | Moderate | Unhealthy+ | Pollutant |
|---|---|---|---|---|---|---|---|
| 2023 | 67 | 101 | 150 | 61 | 260 | 44 | Ozone |
| 2022 | 63 | 97 | 156 | 42 | 297 | 26 | PM2.5 |
| 2021 | 67 | 90 | 133 | 52 | 297 | 16 | PM2.5 |
| 2020 | 74 | 108 | 192 | 33 | 284 | 49 | PM2.5 |
| 2019 | 66 | 93 | 169 | 38 | 302 | 25 | PM2.5 |
| 2018 | 67 | 100 | 143 | 28 | 302 | 35 | PM2.5 |
| 2017 | 68 | 112 | 174 | 41 | 262 | 62 | Ozone |
| 2016 | 68 | 105 | 164 | 30 | 294 | 42 | PM2.5 |
| 2015 | 65 | 102 | 156 | 46 | 278 | 41 | PM2.5 |
| 2014 | 65 | 101 | 170 | 48 | 278 | 39 | PM2.5 |
What This Means for San Diego County Residents
San Diego, California has received an Air Quality Grade of D (36/100) based on a decade of EPA monitoring data. The current median AQI of 67 falls in the "Moderate" range.
The primary pollutant affecting this area is Fine Particulate Matter (PM2.5). Over the past 5 years, this area has averaged 32 unhealthy air quality days per year — days when sensitive groups (children, elderly, those with respiratory conditions) should limit outdoor activity.