Chicago Outdoor Warning System Test Not at Usual Time

Tuesday's Test to Occur at Different Time

Reason for Change Unknown

The City of Chicago's outdoor warning system will be tested on Tuesday, but not at the usual time. The sirens will be activated at a different time on the first Tuesday of each month at 10 am The reason for the change is unknown. The test tone level is at a lower pitch volume.

During a tornado warning, residents will be alerted by a siren sounding a single tone.