Sirens blaring can be unsettling. Understanding why they’re going off is crucial for your safety. This article explains the various reasons for siren activation, focusing on severe weather warnings and tests. We’ll cover who controls the sirens, the different policies for their use, and what you should do when you hear them.
Different Reasons for Siren Activation
While often associated with tornadoes, sirens can be activated for a range of emergencies. These include:
- Tornado Warnings: This is the most common reason for siren activation. A tornado warning indicates a tornado has been sighted or indicated by weather radar. Immediate action is required to seek shelter.
- Severe Thunderstorm Warnings: Some jurisdictions activate sirens for severe thunderstorms with damaging winds (70-80 mph or higher) or large hail. These storms can pose significant threats to life and property.
- Other Severe Weather: Local officials may activate sirens for other hazardous weather events like flash floods, blizzards, or even extreme heat, especially if there’s a significant risk to public safety.
- Civil Emergencies: Sirens can be used to alert the public to non-weather emergencies, such as chemical spills, evacuations, or Amber Alerts.
- Tests and Drills: Regularly scheduled tests ensure sirens are functioning correctly. Drills, like those during Severe Weather Awareness Week, help familiarize communities with emergency procedures. These are typically announced in advance.
Who Controls the Sirens and When Are They Activated?
Local authorities – counties and cities – own and operate the siren systems. The National Weather Service (NWS) issues warnings, but doesn’t control siren activation. Policies vary by location:
- Countywide vs. Localized Activation: Some areas activate sirens across the entire county for any tornado warning, while others use a more targeted approach, activating sirens only in the affected areas.
- Specific Threat Criteria: Criteria for activation can differ. Some jurisdictions activate sirens for all severe thunderstorm warnings, while others only activate them for storms exceeding specific wind or hail thresholds.
- Local Official Discretion: Even without an official NWS warning, local officials may activate sirens if they believe severe weather poses an immediate threat.
Siren Activation Procedures and What to Do
Sirens typically sound for three minutes, then stop. Continuous sounding can drain backup batteries and damage the siren motor. Some areas may repeat the activation every few minutes. Important Note: There is no “all-clear” siren signal.
When you hear a siren:
- Seek Shelter Immediately: Don’t wait for confirmation. Move to a basement or an interior room on the lowest floor, away from windows.
- Tune to Local Media: Seek information from NOAA Weather Radio, local news, or official sources online for details about the emergency.
- Do Not Call 911 for Information: Only call 911 to report emergencies or request assistance. Calling for information can overload the system.
Severe Weather Awareness Week and Drills
Minnesota and Wisconsin hold Severe Weather Awareness Week (April 7-11) to educate the public about severe weather preparedness. Tornado drills are conducted on Thursday, April 10th, at 1:45 PM and 6:45 PM CDT. These drills involve activating sirens and other notification systems as a test.
Knowing Your Local Siren Policy
Contact your local public safety officials or visit your city or county website for detailed information on siren activation policies in your community. Understanding your local procedures is crucial for responding effectively to emergencies.
