Alerting & Notification

An Outdoor Warning Siren System is used to notify the public in case of an emergency and is placed at various locations in the 10-mile Emergency Planning Zone (PDF). Upon activation, the sirens will sound for approximately 3 minutes with a steady, high-pitched sound.

Turn on your radios or televisions. We use the Emergency Alert System (EAS) to provide emergency information and instructions to you through your radios and/or televisions.

EAS stations:

  • KTAR 620 (AM) and 92.3 (FM)
  • KMVP 98.7 (FM)
  • Phoenix National Weather Service forecast office transmits via National Oceanic and Atmospheric Administration (NOAA) Weather Radios

All radio and television stations serving the affected area(s) will be asked to broadcast emergency information as a public service.

Should a siren(s) fail, the Maricopa County Sheriff’s Office will provide warning by telephone, door-to-door contact or loudspeakers mounted on patrol or other vehicles as necessary.

View the Siren Alerting System Facts PDF.