San Francisco Winter AQI: Air Quality Guide
Learn about winter air quality patterns in San Francisco and how to stay safe during this season.
Current Air Quality
Air quality is satisfactory, and air pollution poses little or no risk.
Seasonal Patterns
Winter air quality in San Francisco is influenced by weather patterns, temperature inversions, and seasonal activities. Check our seasonal guides for more information.
View Current Air Quality →PM2.5 Levels
Fine particulate matter data →
Ozone Levels
Ground-level ozone data →
Seasonal Guides
Air quality by season →
Health Effects
Learn about air pollution impacts →
Frequently Asked Questions About San Francisco Air Quality
What is the current air quality in San Francisco?
The current Air Quality Index (AQI) in San Francisco, CA is 37, which is considered good.
Is it safe to exercise outdoors in San Francisco?
Yes, with an AQI of 37, outdoor exercise is safe for everyone in San Francisco.
When is the best time of year to visit San Francisco for good air quality?
Spring and early fall typically offer the best air quality in San Francisco. Summer months may have elevated ozone levels, while winter can see higher PM2.5 from temperature inversions.
What causes air pollution in San Francisco?
Air pollution in San Francisco can come from vehicle emissions, industrial activity, construction, wildfires, and weather patterns. Local geography and seasonal factors also play a significant role.