Monday June 17, Red Flag Warning. No Open Burning in Boulder County

Outdoor Warning Sirens

Outdoor Warning Sirens

Outdoor Warning Siren Outdoor warning sirens provide those who are outdoors and in high-risk areas with audible alerts for flash flood warnings, tornado warnings, or upon request from first responders for imminent life threats. The sirens will broadcast a voice message immediately following the siren signal to inform the public of the situation and what actions should be taken.

The outdoor warning sirens are sounded only in the event of an emergency or during pre-announced tests. The sirens are activated through Boulder County Sheriff’s Communications, and Boulder Police and Fire Communications.

Remember, you are always your first alerting system. Be aware of your environment and trust your intuition; if you see, smell, hear, or sense a hazard make decisions that will ensure your safety.

Siren locations:

Outdoor Sirens are located in some communities around Boulder County including Central Boulder, South Boulder, Eldorado Springs, Erie, Jamestown, Lafayette, Louisville, Lyons, and Superior.

When you hear a siren:

  • Listen for a voice message if you are near an activated siren.
  • Visit for the latest emergency information
  • Tune in to Boulder Municipal Cable Channel 8 (for those who have cable TV in Boulder)
  • Tune in to radio stations KOA 850 AM, KBCO 1190 AM, or 97.3 FM.
  • Tune in to local television news channels (channels 2, 4, 7, 9, or 31).

Siren tests:

Sirens are tested regularly on the first Monday of the month from April through August. The two minute tests are done at 10am and 7pm. The purpose of the two tests is to familiarize and educate people in communities with sirens, and to ensure that sirens are working properly.