The sirens are activated when the National Weather Service issues a tornado warning or when a trained storm spotter sees a funnel cloud. They sound a steady alert tone, which is heard throughout the area for three to five minutes.
Sirens are electromechanical devices, which means they can become clogged by trees, wind, rain or hail. They can also be blocked by high background noise levels from highways, or buildings that are too close to the siren.
They can also go off when a severe thunderstorm is threatening the area, but the storm has not reached its destination. In these situations, the siren is a backup warning system.
When the sirens are going off, stay indoors, don't leave the house or apartment, and monitor the situation by television, radio or weather app. If you are unsure, call the local emergency services department.
When a storm is on the way, we coordinate with the National Weather Service in Wichita and set off a series of tornado warning sirens. We do this to help prevent over-warning and what is called "siren fatigue."
In August of 2018, the county’s outdoor warning system was upgraded to incorporate polygon-specific activations. This means that if the National Weather Service issues a tornado warning, only those sirens within the warned area will be activated.
This is a great change in the way our system works, and it greatly reduces the number of false alarms that citizens experience when listening to the sirens. However, this system is not foolproof and will still be a risk factor in a severe weather event.