About the Air District

San Francisco County

Learn about San Francisco County - its climate, potential air pollution concerns, and current air quality. You can also view upcoming Air District events in San Francisco County and read about local efforts to improve air quality.

Latest News
  • Aug
    1

    August 1, 2022

    Air District’s Climate Tech Finance program funds clean security and lighting solutions to replace diesel generators

    The Air District has awarded a loan guarantee to King Solarman, a provider of smart solar generators in California. Their products replace loud and aging diesel generators used for mobile light towers and surveillance stations.

  • Jul
    27

    July 27, 2022

    Air District extends air quality advisory through Thursday

    The Air District is extending an air quality advisory for wildfire smoke through Thursday, July 28. Winds are continuing to transport smoke from the Oak Fire in Mariposa County into the Bay Area; however, smoke is expected to remain aloft. Smoky, hazy skies may be visible across the Bay Area and the smell of smoke is possible at higher elevations. Air quality is forecast to be in the good to moderate range on the air quality index and pollutant levels are not expected to exceed the national 24-hour health standard. A Spare the Air Alert is not in effect.

  • Jul
    25

    July 25, 2022

    Air District extends air quality advisory through Wednesday

    The Air District is extending an air quality advisory for wildfire smoke through Wednesday, July 27. Winds are forecast to transport smoke from the Oak Fire in Mariposa County into the Bay Area through Wednesday; however, the smoke is expected to remain aloft. Smoky, hazy skies may be visible across the Bay Area and the smell of smoke is possible at higher elevations. Air quality is forecast to be in the good to moderate range on the air quality index and pollutant levels are not expected to exceed the national 24-hour health standard. A Spare the Air Alert is not in effect.

  • Jul
    24

    July 24, 2022

    Air District issues air quality advisory for Monday

    The Air District is issuing an air quality advisory for wildfire smoke for tomorrow, Monday, July 25. Smoke from the Oak Fire in Mariposa County is forecast to be transported into the Bay Area on Monday, however, the smoke is expected to remain aloft. Smoky, hazy skies may be visible across the Bay Area and the smell of smoke is possible at higher elevations. Pollutant levels are not expected to exceed the national 24-hour health standard. A Spare the Air Alert is not in effect.

San Francisco County rests at the northern end of the San Francisco Peninsula, bounded by San Mateo County in the south, the Pacific Ocean to the west, San Francisco Bay to the east, and the Golden Gate Bridge to the north. Three San Francisco County representatives sit on the Air District’s Board of Directors.

Climate

Because most of San Francisco's landscape is below 200 feet, the marine layer flows across most of the city, creating a cool and windy climate. The southeastern portion of the county, however, tends to be warmer and sunnier, with fewer foggy days. In the winter, average daily temperatures are mild overnight and moderate during the day, while summertime temperatures tend to remain moderate throughout the season. The highest wind speeds are focused along the western coast and generally mild throughout the county. Rainfall averages about 20 inches per year, with the highest amounts reported on the western coast.

San Francisco County's climate is also affected by regional Bay Area climate influences.

Interactive Air Monitoring Stations Map

Air Quality in San Francisco County

Ozone and fine particle pollution, or PM2.5, are the major regional air pollutants of concern in the San Francisco Bay Area. Ozone is primarily a problem in the summer, and fine particle pollution in the winter.

In San Francisco, ozone almost never exceeds health standards and PM2.5 only exceeds the national standard once or twice each year, generally. Being surrounded by water on three sides keeps temperatures within a narrow range, whereby winter low temperatures rarely reach freezing and summer high temperatures stay well below levels where ozone would form and become unhealthy.

Interactive Air Quality Forecast Map

Resource Team

San Francisco County Spare the Air Resource Team promotes ways to reduce air pollution in the local community.

Spare the Air Status

Last Updated: 2/14/2019