Severe Weather and Outdoor Warning Sirens. DUPAGE COUNTY OUTDOOR WARNING SIRENS. Emergency Siren Sound Siren Activation Siren Testing. EMERGENCY SIREN SOUND. 3 – 5 minute steady tone It’s one tool used to warn of severe weather You might not hear them if indoors.
Conditions are favorable for severe thunderstorms.
Indicates an immediate danger to those in the path of the storm.
If you see any of these -Take shelter!