SANTA CLARA VALLEY, CA -- The air quality Thursday in Los Gatos and its neighboring Santa Clara Valley communities is expected to be unhealthy for sensitive groups, according to the Bay Area Air Quality Management District, which has issued a "Spare the Air" smog alert for the Bay Area Thursday.

The regional alert, the fourth for smog so far in 2017, is the result of light winds and triple-digit temperatures in the region that are expected to combine with vehicle exhaust to create unhealthy air quality, officials with the air district said.

The region's worst air quality Thursday will be in the Santa Clara Valley and the Eastern District, according to the air district's website, which is forecasting an AQI (air quality index) of 101 for both areas. An AQI between 101 and 150 is considered unhealthy for sensitive groups and means that active children and adults, and people with respiratory disease, such as asthma, should limit outdoor exertion.