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Emergency Management

Outdoor Warning Sirens


​​​​​when sirens sound, seek shelter and seek information


​​​​do you know what this is?

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​​When Do They Sound?​​​​​

The sirens may be activated for several reasons, including but not limited to the following:
  • The National Weather Service issues a Severe Thunderstorm WARNING that includes Coppell and contains a phrase indicating that
    • destructive winds in excess of 70 mph or higher are likely with the storm; and / or
    • destructive hail, 1.5" or larger is likely
  • The National Weather Services issues a Tornado WARNING that includes the city of Coppell
  • Tornadic activity is reported by a reliable source in or approaching the city of Coppell
  • Local Warning Point activation in coordination with the National Emergency Alert System
  • Hazardous materials emergency
  • Catastrophic emergencies that pose an immediate threat to safety (i.e. dam failure)
  • Monthly testing
​The City of Coppell currently operates 17 sirens strategically placed throughout the city. (Interactive Map)

​​​​How Do They Work?​

On any given day, during an emergency or for testing purposes, Coppell's OWS are activated from the Coppell Emergency Operations Center located in Life Safety Park. 
  • ​Sirens are activated locally for the conditions identified above.​​
  • Each activation of the OWS is 3 minutes in duration. There is NO "all clear" signal so just because the sirens stop, that does not necessarily mean that the threat has passed. It is common during a prolonged threat for the sirens to sound a 3-minute activation followed by several minutes of silence and then the cyle is repeated for the duration of the threat.
  • There are two tones used during siren activations, but both are a prompt to seek shelter and seek information:
    • Steady Single Tone is the most common and is used for local emergency warning activations like Tornado warning.
    • The "Alt-Wail" Wavering Tone is used for national warning activations. 
    • The system is also capabile of voice public address and may be used city-wide in exigent circumstances.

​​​​​What Should You Do When You Hear Them?​

  • When the Outdoor Warning "Siren" System activates -- stay calm, immediately seek shelter inside and seek information.
  • Listen to the NOAA All Hazards Weather Radio or local television/radio stations for additional information and specific instructions.
  • Remain indoors until the emergency has ended or directed otherwise.
  • As the name implies, the Outdoor Warning System is intended to warn people outdoors. It is not intended nor designed to provide adequate warning in your home or other indoor locations. Always have more than one means of receiving emergency alerts!

​​​​​​​When Are They Tested?

  • ​Weather permitting, the City of Coppell audibly tests the OWS sirens on the first Wednesday of each month at 1:00 PM. The test includes a Steady Single Tone that lasts for 3 minutes.
  • The City also performs a "quiet test" of the system twice daily. The system activates all functions of each siren short of actually generating the tone. The system automatically notifies emergency management staff of any faults in the system. This functionality helps to assure that the sirens are maintained in working order. 


Coppell Emergency Management
820 S. Coppell Rd
Coppell, TX 75019
O: (972) 462-5326
F: (972) 957-2615