About the Air District

Alameda County

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

Latest News
  • Jan

    January 12, 2021

    Air District’s Charge! Program offers $6 million for electric vehicle charging stations

    The Air District is announcing the availability of $6 million through the Charge! program, which provides grant funding to offset the cost of purchasing and installing new publicly accessible chargers for light-duty electric vehicles.

  • Dec

    December 28, 2020

    Air District settles case with Chevron USA Inc.

    The Air District announced today that Chevron USA Inc. has agreed to pay $147,000 to settle violations at its refinery in Richmond. This settlement covers 29 Notices of Violation issued for air quality violations at the Richmond oil refinery during 2016 – 2018.

  • Dec

    December 21, 2020

    Spare the Air Alert extended through Tuesday due to wood smoke buildup

    The Air District is issuing the winter season’s third Spare the Air Alert for tomorrow, Tuesday, December 22, which bans burning wood, manufactured fire logs or any other solid fuel, both indoors and outdoors. Smoke from increased wood burning is expected to cause air quality to be unhealthy with the heaviest impacts in the Santa Clara Valley due to cold overnight temperatures and light winds.

Alameda County lies east of the San Francisco Bay, bounded by Contra Costa Bay to the north, San Joaquin County to the east, and Santa Clara County to the south. Four representatives sit on the Air District’s Board of Directors.


Along the county’s western coast, temperatures are moderated by the bay, which can act as a heat source during cold weather, or cool the air by evaporation during warm weather. It is generally sunnier farther from the coast, although partly cloudy skies are common throughout the summer. Average summer temperatures are mild overnight and moderate during the day. Winter temperatures are cool overnight and mild during the day. Highest temperatures are more common inland. Wind speeds vary throughout the county, with the strongest gusts along the western coast, often aided by dominant westerly winds and a bay-breeze effect. Rainfall totals average about 14 to 23 inches per year, with the highest totals in the northern end of the county and atop the Oakland-Berkeley hills.

Alameda County’s climate is also affected by regional Bay Area climate influences.

Interactive Air Monitoring Stations Map

Air Quality in Alameda 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 Alameda County west of the East Bay hills, ozone rarely exceeds health standards because the area is adjacent to San Francisco Bay, which tends to keep temperatures well below prime levels for ozone formation.  PM2.5 is a more significant issue in this region due to cool winter nights with light winds, wood smoke, and occasional pollution transport from the Livermore Valley to the east.

Eastern Alameda County has the highest ozone levels in the Bay Area, with summer afternoon temperatures frequently approaching triple digits, spurring ozone levels to exceed health standards. In winter, PM2.5 can be transported westward through the Altamont Pass from the Central Valley where it adds to wood smoke levels, causing health standards to be exceeded.

Interactive Air Quality Forecast Map

Resource Team

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

Spare the Air Status

Last Updated: 2/14/2019