Early Warning System Sirens


San Luis Obispo County's Early Warning System Sirens would sound to alert area residents and visitors to tune to a local radio or television station for information. The sirens alert you that an emergency is taking place within the County and possibly at Diablo Canyon Power Plant. There are 131 sirens located in Protective Action Zones 1 through 12, stretching from Cayucos in the north to Nipomo Mesa in the south.

Residents may also be alerted by sirens and loud speakers used by police and fire agencies in the case a siren fails to sound.

If you hear a loud, steady siren for three to five (3-5) minutes:

  • Go indoors and tune to a local radio or television station. Stay tuned and listen for important information and instructions.

  • If you are able, go to your neighbors and make sure they are aware of any emergency warning and related emergency actions.

  • Tune to Marine Channel 16 for emergency information if you are at sea.

  • Only call (805) 543-2444 if you urgently need information or assistance during an evacuation. The County Office of Emergency Services activates this phone line only when there is an emergency that affects large numbers of people in the county.


  • Do not call 911! 911 is an emergency line for people who need urgent medical, fire, or police help. Using 911 for information ties up the system and may delay help for someone who needs it.

  • Do not leave the area unless you are told to do so over the Emergency Alert System (see below)

  • Do not use your telephone unless you need to call for help.

  • Do not call local police, fire, or sheriff's offices unless you need their immediate help during an emergency. Please leave telephone lines open and emergency personnel available for people who need immediate lifesaving help.

Local Radio and Television Stations

The Emergency Alert System (EAS) is used to inform you about the nature of the emergency and what steps you should take. All local radio and television stations are part of the Emergency Alert System and will broadcast and repeat official information about major emergencies.

Listen to any local radio station for further information and instructions. If at sea, Marine Channel 16 will carry emergency information.

Access WebEOC

Contact OES via web form, email, or call us at (805) 781-5011.