Outdoor warning sirens may not be heard inside buildings. They are primarily intended to warn persons in outdoor areas.
It is estimated that about 50% of the public can hear a siren on a still day. During heavy rains or stormy weather, the percentage of people who hear a warning siren is greatly reduced because of the noise associated with the storm and because more people are indoors.
It is recommended that you opt-in to the other methods to receive Emergency Communications. To get started, visit the Emergency Alerts webpage.
If you would like to submit commentary about the testing, please reach out to the Boulder County Office of Disaster Management.