Outdoor Warning Sirens

Outdoor warning sirens are used to alert people who are outside to go indoors and seek shelter in a hazardous situation.

CEMA has received funding in the FY24 City Budget to replace the outdoor warning siren system. The process to identify systems needs and to select a contractor to perform the work is underway. To ensure you receive all emergency alerts, including tornado warnings and severe thunderstorms designated destructive, sign up for NotifySTL Alerts.

CEMA operates sixty warning sirens located throughout the city, many at local fire houses. The sirens are maintained and repaired through a partnership with the St. Louis City Street Department. The Outdoor Warning Siren system is activated in the City of St. Louis, any time there is a tornado warning or a severe thunderstorm warning that has been designated destructive by the National Weather Service.

This is an OUTDOOR warning system and is meant to direct residents and visitors to go indoors during a severe weather emergency.

It is recommended that upon hearing the siren, you immediately seek shelter and refer to the local media or a NOAA weather radio for further information or updates.

The City of St. Louis does not utilize the siren system to issue an "All Clear". Any siren activation is meant to prompt immediate action!

The siren system is ONE tool we use to warn those in the city of emergency weather situations. It is suggested that you subscribe to our emergency alert system, NotifySTL, and use a NOAA Weather radio in your home to be sure you receive all important alerts.

Sirens are tested at 11am on the first Monday of each month. If a siren test has been canceled, CEMA will send an alert to NotifySTL.

Sirens may be activated for the Missouri Statewide Tornado Drill which usually occurs the first week of March each year.

Outdoor Warning Sirens

Outdoor warning sirens are used to alert people who are outside to go indoors and seek shelter in a hazardous situation.

Publication Date: 09/15/2010
Document Type: Informational Pages
Sponsor: City Emergency Management Agency


  1. pdf Warning Siren Fact Sheet (764.78 KB)

Need Help Viewing?

You need a program that can open Adobe PDF files. A free option:

Siren Tests 

Sirens are tested on the first Monday of every month at 11:00 a.m., unless there is inclement weather.  The siren will sound for three minutes.

Report a siren that does not sound during the monthly test. Be sure to include your approximate location so that we can locate the appropriate siren.

The City of St. Louis also participates in the Missouri Statewide Tornado Drill each spring (when it does not conflict with local elections), activating the sirens and encouraging residents to practice what they would do in the event of an actual tornado.

Sirens not Working?

Choose one of the following method to report a problem with Disaster Preparedness Testing of Weather Sirens:

Was this page helpful?      

Comments are helpful!
500 character limit

Feedback is anonymous.

1 comment from someone like you has helped us improve this page. Keep the feedback coming!