Sirens are a way to warn people who are outdoors and in an immediate threat to safety. They are primarily intended to warn individuals in outdoor and high-risk areas. The outdoor warning sirens are sounded only in the event of an emergency or during per-announced tests. In hazardous conditions Killeen’s sirens will sound for 3 to 5 minutes.

Sirens are activated for: Tornado warnings; Hail greater than 1.5"; Severe thunderstorm warning with winds greater than 70 MPH and other emergencies as directed by the Office of Homeland Security & Emergency Management.

The Office of Homeland Security & Emergency Management performs an audible test on the sirens the 3rd Wednesday of each month at 2 p.m. During these tests, the horn sounds for 3 minutes. This test is subject to cancellation depending on the weather.