Outdoor Warning Siren System

2024 Oakland County Siren Test Calendar

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 275 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 Emergency Management.

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.

Tests occur the first Saturday of the month from March through November. 

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