Public safety officials from the City of Ankeny and Polk County would like to ensure that all residents understand the policy for initiating the Polk County Severe Weather Outdoor Emergency Warning System.
The warning system is in place to warn residents of tornados or severe thunderstorms with wind speeds expected to reach or exceed 70 mph.
When the sirens are activated, go inside to the lowest level, most-interior room of the structure and tune to NOAA All-Hazards Radio or the local media for more detailed information on the storm’s location, timing, and intensity.
Some residents have misconceptions about how and when the outdoor warning system is activated. Please be aware of the following:
- The outdoor warning system is designed only to inform those who are outside in the open areas, of a tornado warning issued for the area. The system is not designed to warn residents within the confines of a residential, commercial, educational or other occupancy.
- The sirens will sound in a cycle of 3-5 minutes, re-sounding every 10-15 minutes for the duration of the threat (warning period). Residents need to monitor the previously mentioned sources for information regarding when the threat has diminished.
- Warnings are officially issued by the National Weather Service (Johnston, Iowa) and are received at all three Public Safety Answering Points (PSAP)/911 Communication Centers in Polk County. Specific to Ankeny, sirens are activated by the dispatch consol at the Polk County Communications Center.
- In the event of an actual sighting of a tornado in the area, observed prior to a warning issued by the NWS, law enforcement, fire service or emergency management agency supervisors can request that the sirens be activated.
- The system is not activated for thunderstorms, other severe weather conditions or perceived imminent hazards after the initial tornado warning activation has been made.
- The warning sirens will not be activated to signal an “all clear.”
- In the event that a previously issued tornado warning expires, and the NWS issues a fresh tornado warning for the area, the warning system will be activated again in response to the new warning.
- Residents are asked to refrain from calling 9-1-1 to question the activation or non-activation of the outdoor warning sirens. This places an undue burden on the 9-1-1 system and prevents true emergency calls from getting through.
The intent of the sirens is to provide ample warning for persons to seek shelter and additional information before the storm hits. Because of this, sirens may sound before hazardous conditions exist. Due to the nature of severe weather, hazardous conditions may also develop before an activation of the sirens is possible.
The safest approach is to be proactive and use all of the information available to protect yourself and your family from threatening weather. Nothing can replace common sense. If a storm is approaching, the lightning alone is a threat. Sirens are only one part of a warning system that includes preparation, NOAA All-Hazards Radio, and the local media.
Outdoor warning sirens shall be tested on the first Saturday of each month at 12:00 p.m. (noon). A “growl” test may be performed on the third Saturday of each month at 12:00 p.m. A “growl” test activates the system without the full audible alert.
If a severe weather watch or warning is in effect for Polk County area prior to 12:00 p.m. on a scheduled test day, the sirens should not be tested that day. Outdoor warning siren tests will resume on the next scheduled monthly date.
Testing may be suspended during the winter months (December – February) when ice or sub-zero temperatures could damage the siren system. Testing should be considered condition-dependent during these months. Testing schedule should be maintained whenever possible for continuity purposes as well as system reliability.
If testing is required at any time outside of the normal monthly testing schedule, Polk County Emergency Management Agency shall be notified. Polk County Emergency Management Agency will then notify the media to better ensure awareness by the public of the additional testing and hopefully reduce the number of concerned callers to the Public Safety Answering Points (PSAPs).
If your siren is not functioning properly you should contact the Polk County Emergency Management Agency at 515-286-2107. They will need to know the siren location and description of the problem in order to direct the maintenance/repair request to the proper jurisdiction.