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The Outdoor Warning Siren System (OWSS) is an outdoor, all-hazards siren system that is used to warn the general population of a potential danger in a short amount of time. The system is designed to provide coverage to persons out of doors, not inside buildings or structures.
What Do the Sirens Mean?
- The OWSS will be activated upon receipt of a tornado warning issued by the National Weather Service (NWS) for Polk County.
- Severe Thunderstorm Warnings where forecasted or actual wind speeds reach or exceed 70mph (61kts)
- Sirens will sound in a cycle of 3-5 minutes, followed by a 10-15 minute break for the duration of the threat (warning period).
Please note that cities do perform a monthly siren test to ensure all sirens are functioning. The entire system is tested at noon on the first Saturday of each month unless severe weather is imminent.
What Should I Do if I Hear the Sirens?
If the sirens are activated – and it is not a monthly test – the public should see it as a signal to:
- Seek shelter
- Tune into radio or television to get information about:
- Type of Emergency
- Instructions & Recommendations
The public should not call 9-1-1 unless they have an actual emergency.