The Emergency Alert System (EAS) is a national public warning system that requires broadcasters, satellite digital audio service and direct broadcast satellite providers, cable television systems, and wireless cable systems to provide the U.S. president with a communications capability to address the American people within 10 minutes during a national emergency. 
EAS may also be used by state and local authorities, in cooperation with the broadcast community, to deliver important emergency information, such as weather information, imminent threats, AMBER alerts, and local incident information targeted to specific areas. 
The president has sole responsibility for determining when the national-level EAS will be activated. FEMA is responsible for national-level EAS tests and exercises. 
EAS is also used when all other means of alerting the public are unavailable, providing an added layer of resiliency to the suite of available emergency communication tools. 

San Mateo County’s EAS stations include: 

KCBS 740 AM and 106.9 FM 

KQED 88.5 FM 

KCSM 91.1 FM 





KNTV-11 (NBC Bay Area)