Be ready for severe weather before the sirens go off

By Emily Steele and Duane Friend University of Illinois Extension Services

Every community has a different siren use practice
, but in Illinois s
irens may sound for
weather alerts such as a tornado, hail, and extreme winds.
(Photo courtesy of NOA

Weather can change from blue skies to ominous clouds in an instant in Illinois. When the wail of an alert siren is heard, it’s a warning sign that should not be ignored.

Illinois Severe Weather Preparedness Week is Feb. 28 to March 4. This may seem early, but it is a chance for communities to prepare before any spring severe weather events. As part of that preparation, many communities will test their Public Alert System.

Duane Friend, University of Illinois Extension Energy and Environmental Stewardship educator, says the siren alert systems were originally designed for civil defense purposes and are now also commonly used by local authorities to notify anyone outdoors about severe weather.

Every community has a different siren use practice. In Illinois, sirens may sound for weather alerts such as a tornado, hail, and extreme winds.

“This means the storms are close and may affect those who can hear the alert,” Friend says. “It’s important to realize that sirens are only meant to provide a warning to individuals that are outdoors. They are not meant to be heard well indoors.”

When an alert goes off, head to a safe location such as a sturdy building or a vehicle if a building is not nearby. The siren is also a cue to turn on a radio or television for emergency updates.

A weather alert is a steady siren signal for three to five minutes. A civil defense alert will be more of a warbling up and down sound, much like an air raid siren.

In most communities, weather alerts are regulated and activated by local authorities such as police and fire departments or local emergency management personnel. They also test systems monthly. In Illinois, sirens are tested on the first Tuesday at 10 a.m.

“New technology options give these agencies greater flexibility to operate and test their sirens from a safe remote or centralized location such as an emergency operations center,” Friend says.

To stay safe during severe weather, be prepared and informed. The National Weather Service recommends knowing how local warning systems work, investing in a NOAA weather radio, and acting when severe weather strikes.

To learn more about disaster preparation and recovery, explore Illinois Extension resources at or visit the Illinois Emergency Management website at