The Air District is issuing the winter season’s first Spare the Air Alerts for Wednesday, November 26, and Thanksgiving Day, which bans burning wood, manufactured fire logs or any other solid fuel, both indoors and outdoors.
Learn about San Mateo County - its climate, potential air pollution concerns, and current air quality. You can also view upcoming Air District events in San Mateo County and read about local efforts to improve air quality.
The Air District is issuing the winter season’s first Spare the Air Alerts for Wednesday, November 26, and Thanksgiving Day, which bans burning wood, manufactured fire logs or any other solid fuel, both indoors and outdoors.
The public comment period for the Draft Guidelines for the Local Community Benefits Fund for Benicia, Richmond, and surrounding areas closes on Tuesday, November 25, at 5:00 PM. The Draft Guidelines describe the Local Community Benefits Fund, which will reinvest penalty funds back into communities impacted by air quality violations, supporting local projects that improve public health, reduce pollution, and promote a just transition.
The Air District is announcing the launch of its Commercial Electric Lawn and Garden Equipment Exchange Program, a pilot grant program designed to reduce air pollution by replacing gasoline and diesel-powered landscaping equipment with cleaner, zero-emission electric alternatives.
The Air District showcased the Bay Area’s leadership in clean air, climate innovation, and equity at the United Nations Climate Change Conference or COP30, held in Belém, Brazil from November 10 through November 21. During a virtual media availability on November 13, Air District leadership reflected on the importance of local and regional action to drive global climate progress.
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San Mateo County lies in the middle of the San Francisco Peninsula, south of San Francisco County, and north of Santa Clara and Santa Cruz counties. It is bounded by the Pacific Ocean to the west and San Francisco Bay to the east. Two San Mateo County representatives sit on the Air District’s Board of Directors.
Cool, foggy weather is prevalent along the western coast of the peninsula, particularly during the summer. Summertime average daily temperatures are moderate along the west coast and warm in the county’s east side. In the winter, average daily temperatures across the county range from mild to moderate. Winds are mild, with the highest wind speeds focused along the western coast. Rainfall averages about 20 to 25 inches per year at lower elevations and up to 36 inches in the Santa Cruz Mountains.
Interactive Air Monitoring Stations Map
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 Mateo County, ozone almost never exceeds health standards, and PM2.5 exceeds the national standard only on about one day each year. San Mateo County frequently receives fresh marine air from the Pacific Ocean, which passes over the coastal hills. In winter, PM2.5 may be transported into San Mateo County from other parts of the Bay Area, adding to wood smoke, which may lead to elevated concentrations, but these are rarely high enough to exceed health standards.
Last Updated: 4/21/2017