Not every neighborhood in Aurora, Colorado has tornado sirens 03:26. Across much of Aurora, there are dozens of outdoor emergency sirens. It's technology that's been used for decades, but one the ...

Some tornado-plagued cities now rely on cell alerts Brighton says 12 sirens protect roughly 42,000 residents in this area but police say there’s something you should do when you hear one of them.

Denver tested its tornado siren system on Wednesday morning ahead of severe weather season. The outdoor warning siren sounded at 11 a.m. and lasted three minutes.

Denver’s tornado sirens can’t communicate messages. To the east, Aurora’s sirens used to transmit messages and still can. But emergency managers don’t use that capability anymore.

There’s not a tornado, and the sky is not falling. If you’re in Wheat Ridge, the loud blaring you hear between 11 a.m. and noon is a test.

Denver is expanding its use of tornado sirens to include life-threatening events such as dangerous flooding, wildfires and hazardous materials. Recent local and national disasters, including the ...

Outside, 86 tornado warning sirens across Denver went off simultaneously. The loud sound caused some to stop and look around. But in Denver's Emergency Operations Center, it was quiet.