Summer

During the summer months when ground-level ozone, or "smog," becomes a pollution problem, the Air District issues Spare the Air Alerts for days on which air quality is forecast to be unhealthy.

These advisories are posted on our website with our daily air quality forecasts, recorded on our 1 (800) HELP AIR forecast phone line, announced in local newspapers, and broadcast on local TV and radio stations.  The EnviroFlash AirAlert email system also notifies registered Bay Area subscribers.

In the Bay Area, the summer Spare the Air season generally runs from April through October when clear skies, hot temperatures, lighter than usual winds, and strong temperature inversions combine to create smoggy conditions.  Spare the Air Alerts are declared for days forecast to have ozone concentrations that exceed federal health-based standards.

On these Spare the Air days, we urge residents to cut back on any activities that cause pollution - such as driving, using oil-based paints, gasoline-powered lawn mowers, or household aerosol products like hair sprays.  People who are sensitive to unhealthy air are advised to limit their time outdoors, particularly in the afternoon hours.

• Learn more about the health effects of ozone.
• View historical "box scores" listing the number of times ozone standards have been exceeded on an annual basis in the Bay Area.
• Watch Bay Area Ozone Animations showing smog activity on selected days.
• Read the Spare the Air FAQs.