Air Quality Forecast

Monday, July 15
Mon
Tue
Wed
Thu
Fri
Northern Zone
33
33
G
G
G
Coast and Central Bay
33
38
M
M
G
Eastern Zone
34
33
G
G
G
South Central Bay
33
28
G
G
G
Santa Clara Valley
37
31
G
G
G
Last Updated: Monday, July 15 at 11:08 AM

How the Forecast Affects Alerts

Air is almost always on the move, and it is easy for pollution to drift from one reporting zone to another. This is particularly true in the Bay Area where winds can blow pollution from one location into neighboring valleys.

That is why a Spare the Air Alert or Winter Spare the Air Alert is called for the whole Bay Area when air quality is forecast to be unhealthy in any one of the five reporting zones: Northern Zone, Coast and Central Bay, Eastern Zone, South Central Bay, and Santa Clara Valley.

Reporting zones are different from county lines. They are defined by air current patterns and geographic features that lead to shared air quality within certain areas.

The Air District issues a daily forecast that predicts air pollution levels for the coming five-day period. A Spare the Air Alert or Winter Spare the Air Alert is called when air quality is forecast to be unhealthy in any one of the reporting zones. An alert may span over several days if air quality is expected to remain unhealthy.

The daily forecast is available by signing up for email ‌AirAlerts or calling the Air District’s 24-hour, toll-free information line (1-800-HELP AIR).

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San Francisco Bay Area
Air Quality Status
Monday, 7/15
No Alert
Tuesday, 7/16
No Alert

5-Day Air Quality Forecast
Mon
Tue
Wed
Thu
Fri
Northern Zone
33
33
G
G
G
Coast and Central Bay
33
38
M
M
G
Eastern Zone
34
33
G
G
G
South Central Bay
33
28
G
G
G
Santa Clara Valley
37
31
G
G
G
Monday, July 15
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