Outdoor Public Alert Sirens in Pennington County will be used to notify citizens of impending danger. Sirens can be sounded for any life-threatening, all-risk, all-hazard emergency from natural threats or human-caused threats including high winds, large hail, wildfires, acts of terrorism, dam failure, flash floods, tornadoes, and spills of hazardous materials.

When an outdoor siren activates in Pennington County it will be a steady, constant tone, (not a beeping or high/low tone). It is intended to let people outside know that there is some type of imminent threat and that they should turn on broadcast media (local TV / Radio) or listen to NOAA radio to learn specifically what is happening, specifically where the threat is, and what the recommended protective actions are.

Pennington County has 34 sirens to alert of impending danger located in Box Elder, Hill City, Keystone, New Underwood, Rapid City, and Wall. These sirens are tested at noon on the 1st and 3rd Saturday of each month. If you hear the siren at any other time, please tune into your radio or local news station for more information. 

Outdoor Public Alert Sirens graphic
0 found in 0 section(s)

Outdoor Alert Siren FAQ’s

The sirens are used to notify citizens who are outdoors that they need to seek shelter immediately and turn on their TV or radio for information.

Sirens are sounded for any life-threatening, all-risk, all-hazard emergency from natural threats or human-caused threats as determined by key public safety officials, including high winds, large hail, wildfires, terrorism, dam failure, flash floods, tornadoes, and spills of hazardous materials.

They are activated automatically based on criteria established by key public safety officials.
When an incident occurs, depending on the location and scale of the emergency occurring, sirens in or near the incident area may be activated. For the monthly tests, all sirens are activated.

These two Saturdays each month** are a regular siren test to ensure that the sirens receive the activation signal and also to confirm they are functioning properly.

**Saturday SIREN TESTS ARE HISTORICALLY PAUSED for the months of January & February. 

2026 Update: The Outdoor Alert Siren tests, usually conducted on the 1st and 3rd Saturdays of each month, will be temporarily suspended or paused, during January and February 2026. Specifically, there will be no tests on January 3 and 17 or February 7 and 21.

Pole-mounted outdoor sirens are intended as an "OUTDOOR" alert. They are designed to notify people who are outside and would not normally be near a radio or TV to hear or see that a dangerous incident may be occurring. With current construction methods and sound insulation, achieving sound penetration into structures is difficult. A home or business may or may not hear a siren sound. For this reason, Pennington County Emergency Management recommends that each business and household purchase a weather alert radio as another layer of notification.
There is not a "volume adjustment" on the siren; however, sirens may seem louder in the fall and winter as there is less foliage to absorb the sound. Some sirens also rotate which can make them seem louder or softer depending on the rotation while they are activated.
Here in Pennington County we only use the steady "on" tone to alert for any rapidly developing, life-threatening situation. Different models of sirens are capable of making different high and low tones. These varied tones go back to the Cold War Civil Defense days when sirens were required to have different sounds for "air raids" and "civil emergencies."
In most cases, the siren should sound before severe weather could affect power. Most sirens have battery backup and will still sound if power is lost.
Sirens are checked annually along with being tested during the monthly tests. If a siren near your home or office is malfunctioning or has an unusual sound, please contact the Emergency Management office during regular business hours, or after hours contact the non-emergency 911 Dispatch number (394.4131).
A new siren, including electronics to operate it, a pole or other structure to mount it on, and battery backup, can average $20,000.00 or more per siren, depending on different configurations.
Currently, there are 34 sirens strategically placed throughout our county. See the map links located above for locations.
Pennington County Emergency Management will take a look at a couple of different things. The primary factor in determining a location is the level of outdoor activity in an area, such as a sports complex. We also look at available land, power, and suitability of coverage.