There are emergency sirens in Oakland. They are tested the first Wednesday of the month at noon. If you hear a siren at another time, you should tune into local emergency broadcast news stations KGO, KCBS, KNBR or the city’s 530 AM radio. [Note - They just went off Friday 02/03/2017 at noon - confirmed from Oakland Police department that this was a test].
The sirens were funded by a 1992 bond to have a coordinated early warning system in case of fire. In 2003 Alameda, San Leandro and Oakland launched the "Corridor of Safety" to alert residents in the case of a disaster. They developed a "Alerting and Warning Siren System" to alert and inform the public and to train them to follow the "Shelter, Shut and Listen" system. The system started February 5th, 2003. As of 2003, there were 27 sirens in Oakland.
In January, 2017, they began testing the sirens as part of a citywide upgrade. Until the upgrade is complete, people in affected areas will be warned by a reverse 911 system if needed. 1
Another test is planned for February 10th, 2017:
A full-system test of the City of Oakland’s Emergency Sirens is planned for noon, Friday, February 10.
At noon, a 90-second, slow wail will sound from all of the sirens. This first test will be followed about 15 minutes later by another 90-second, slow wail.
Map of Sirens (From 2003)
FAQ about Sirens (From 2003)
Links and References
Oakland to Begin Upgrades on Emergency Siren System Rockridge Patch