Inland locations can experience more variable air quality due to limited natural ventilation and local emission sources.
In line with average conditions across San Francisco
24-Hour AQI Trend
Pollutant Breakdown
Peer Comparison
In line with average conditions across San Francisco
Why Union Square, San Francisco's Air Is What It Is
Union Square, San Francisco sits in an inland urban setting where local environmental conditions are shaped primarily by density and development patterns. Temperature swings between day and night can be more pronounced than in coastal areas.
Historical Context
Current AQI of 31 reflects recent monitoring data. Local conditions can shift with weather patterns, traffic volume, and seasonal factors.
24-Hour Hourly Forecast
Best window: Check real-time conditions · Peak AQI: 31 at Now
| Time | AQI | Temp (°F) | Humidity | Wind (mph) | PM2.5 | PM10 |
|---|---|---|---|---|---|---|
| Hourly forecast data updates throughout the day — current AQI is 31. Check back for the full 24-hour outlook. | ||||||
Current air quality is good — ideal for outdoor activities. Check the hourly forecast for the best windows.
The Union Square, San Francisco Environmental Profile. Residents of San Francisco often cite the area's Good air quality as a key factor in their quality of life. Across 94104, environmental data suggests a community that prioritizes sustainable practices. For those visiting Union Square, San Francisco's parks during early morning or evening hours, it may be helpful to choose areas with good lighting and visible pathways. Many parks in San Francisco have designated hours of operation posted at entrances.