Outdoor Warning Siren System

When the National Weather Service issues a Tornado Warning or a Severe Thunderstorm with damaging winds at or greater than 70 mph for Oakland County, the sirens are activated.

Oakland County has 277 outdoor warning sirens located throughout Oakland County. All sirens are activated by the transmission of an RF signal with a tone alert. The signal is transmitted by the Oakland County Homeland Security Division.

When sirens are activated a steady three minute tone indicates a tornado has been sighted or strongly indicated on radar and/or a severe thunderstorm with 70 mph winds or greater is in the area. Seek shelter immediately and listen to radio or television for more information, if it is safe to do so. Do not call police, fire departments or news media.

Each siren is capable of covering about a one mile radius from its location. The sirens are designed to alert citizens who are outside but citizens inside buildings may hear the siren if they are close to the siren location.

It's up to you!

Every year, many people are killed or seriously injured by tornadoes and/or high winds despite advance warning. Some do not hear the warning, while others received the warning but did not take action. This information, combined with timely severe weather watches and warnings, could save your life when severe weather threatens your area. After you have received the warning or observed threatening skies, YOU must make the decision to seek shelter before the storm arrives.  It could be the most important decision you will ever make!

Oakland County Homeland Security will be testing the Outdoor Warning Siren sys​​​​tem in 2020 on the first Saturday of each month at 1:00 PM, with the following exceptions:

  • April 4 (Saturday); cancelled due to Severe Weather Awareness Week testing.
  • March 25 (Wednesday) at 1:00 PM; special test in recognition of Severe Weather Awareness Week.

Siren tests are NOT conducted during December, January, and February due to winter weather.​