Safety Tips/Guidelines

Hamilton County Siren Alerting System


As a reminder, the outdoor warning sirens in Hamilton County are tested the first Wednesday of each month at noon unless inclement weather is imminent.

There are four basic criteria to activate the sirens:

  • The National Weather Service issues a Tornado Warning for all or part of Hamilton County,

  • A trained and certified weather spotter reports a tornado; 

  • A tornado is reported by a local public safety official; or

  • A dangerous situation occurs which requires citizens to seek shelter immediately.


Hamilton County has the capability of activating all of the sirens at once or by activating one or more of six established siren zones. All sirens may be sounded unless the threat is clearly confined to an individual zone (or zones). During a tornado warning, the sirens will be sounded for a three-minute duration in ten minute intervals (three minutes on, seven minutes off) for as long as the tornado warning is in effect. There is NO “all-clear” siren.


For additional information on severe weather safety and preparedness, visit the Hamilton County Emergency Management and Homeland Security Agency website at: