San Francisco Air Quality in June
Across 2019–2025, San Francisco's June air quality had a median AQI of 53 (Moderate) over 189 monitored days in the San Francisco-Oakland-Hayward, CA area. 4.2% of June days (8 of 189) reached Unhealthy for Sensitive Groups or worse, and fine particulate matter (PM2.5) set the daily AQI on 78.8% of days. The cleanest June on record here was 2020 (median AQI 48, 0 days above 100) and the worst was 2023 (median 57, 3 days above 100, peak AQI 104).
- Good: 41.8%
- Moderate: 54.0%
- Unhealthy for Sensitive Groups: 3.7%
- Unhealthy or worse: 0.5%
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How is the air in San Francisco in June?
Moderate on a typical day: median AQI 53 across 2019–2025, with 4.2% of June days above AQI 100. Fine particulate matter (PM2.5) is the main driver.
- ✓41.8% of June days were Good (AQI 0–50), 54.0% Moderate (51–100).
- ✓8 days of 189 reached AQI 101+; the June peak was 151.
- ✓Best June: 2020; worst June: 2023.
Frequently asked questions
What is the air quality like in San Francisco in June?▾
Across 2019–2025, the median daily AQI in San Francisco in June was 53 (Moderate). 41.8% of days were Good, 54.0% Moderate, and 4.2% reached Unhealthy for Sensitive Groups or worse, based on 189 monitored days in EPA's Air Quality System.
Is June a good time for outdoor exercise in San Francisco?▾
A typical June day in San Francisco is Moderate (median AQI 53): outdoor exercise is acceptable for most people, but unusually sensitive individuals should watch for symptoms, and about 1 day in 24 of June days (4.2%) reached AQI 101+ — the level at which EPA advises people with asthma, children and older adults to shorten hard outdoor exertion.
Which pollutant causes San Francisco's June air quality problems?▾
Fine particulate matter (PM2.5) set the daily AQI on 78.8% of June days in San Francisco. The highest June AQI recorded in 2019–2025 was 151 (Unhealthy), in 2023.
San Francisco June air quality, year by year
San Francisco June air quality by year (San Francisco-Oakland-Hayward, CA, EPA AQS daily AQI)
| Year | Days monitored | Median AQI | Days above 100 | Peak AQI | Main pollutant |
|---|---|---|---|---|---|
| 2019 | 30 | 54 | 3 | 150 | PM2.5 |
| 2020cleanest | 30 | 48 | 0 | 71 | PM2.5 |
| 2021 | 30 | 45 | 2 | 151 | PM2.5 |
| 2022 | 30 | 53 | 0 | 90 | PM2.5 |
| 2023worst | 30 | 57 | 3 | 104 | PM2.5 |
| 2024 | 30 | 61 | 0 | 75 | PM2.5 |
| 2025 | 9 | 48 | 0 | 56 | PM2.5 |
What June air means in San Francisco
A typical June day in San Francisco is Moderate (median AQI 53): outdoor exercise is acceptable for most people, but unusually sensitive individuals should watch for symptoms, and about 1 day in 24 of June days (4.2%) reached AQI 101+ — the level at which EPA advises people with asthma, children and older adults to shorten hard outdoor exertion.
June's median AQI of 53 is in line with San Francisco's whole-year median of 53, so this period is neither a clean nor a dirty stretch for the area. Nationally, the median June AQI across every EPA metro area (100,635 metro-days, 2019–2025) is 46, so San Francisco runs above the national June norm; 4.2% of its June days topped AQI 100 versus 3.7% nationally (about the same).
June is part of San Francisco's summer season (June, July, August); the summer page pools all three months.
Activity-specific thresholds: running, cycling, kids' sports.
Right now in San Francisco
The latest EPA AirNow observation puts San Francisco's AQI at 36 (PM2.5). The figures above are multi-year month statistics, not today's reading.
View current San Francisco air quality →Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (San Francisco-Oakland-Hayward, 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.