Emergency population warning

An emergency population warning is a method where by local, regional, or national authorities can contact members of the public to warn them of an impending emergency. These warnings may be necessary for a number of reasons, including:

• Weather emergencies such as tornadoes, hurricanes, and ice storms.
• Geological disasters such as earthquakes, landslides, volcanic eruptions, and tsunamis.
• Industrial disasters such as the release of toxic gas or contamination of river water.
• Radiological disasters such as a nuclear plant disaster.
• Medical emergencies such as an outbreak of a fast-moving infectious disease.
• Warfare or acts of terrorism.

Many local areas use emergency population warnings to advise of prison escapes, abducted children, emergency telephone number outages, and other events.