The Colleyville Outdoor Warning System consists of eight sirens in a broad geographical cross-section of the city. The system provides alert coverage in densely populated residential, business and public areas, to alert the greatest number of citizens. Colleyville’s Outdoor Warning System, together with neighboring cities' sirens, provides full coverage of the city. 

The Outdoor Warning System is tested the first Wednesday of each month at 1 p.m.

Remember: The emergency alert siren is for outdoor notification.
When the warning sirens are activated citizens should:

• Go inside right away.
• Turn on a radio or television to hear the latest weather or emergency information.
• Take shelter in an inside room or basement if appropriate.
• Keep in mind:
  • The sirens are not a signal to evacuate. Your area may not be affected by an emergency, or you may be asked simply to remain indoors for a period of time. You will be given specific instructions about whether to stay inside, leave the area or take other protective action.
  • Do NOT call 9-1-1 when you hear the siren. Local media, National Weather Service, or Emergency Alert System will provide updated information. Citizens should use their televisions or radios to get these updates.