Warnings and Alerts

One of Emergency Management's primary responsibilities is to issue public warnings related to potential threats. To do that, Emergency Management works in cooperation with many agencies, including the National Weather Service, first responders and the County Office of Public Information. The goal is to push out accurate information and warnings through multiple sources, as quickly as possible, in order to alert as many residents and visitors in our area as possible.

Alerting methods that are commonly used include television, radio and other media outlets; warning sirens; NOAA Weather Radio and websites. In recent years, alerting capabilities are expanding to include text and email messaging, social media and various online apps. Other sources, such as electronic roadway signage, are coming in the near future. Used together or individually, these resources can keep residents and travelers aware and informed before, during and after emergencies.

However, it is important to remember that each of these methods does have its limitations. Because any of these methods can be damaged or interrupted, residents are encouraged to have more than one method to receive alerts and warning information.

NOAA Weather Radio

NOAA Weather Radio

Types of Alerting Systems

Emergency Alert System (EAS)
The Emergency Alert System is used to send warnings and information via broadcast, cable, satellite and wire-line communications pathways out to the public through radio and television stations. Regularly scheduled programming can be interrupted to send out emergency announcements when necessary. The EAS may be used along with other alerting systems, or alone if all other means of alerting the public are unavailable. EAS is managed jointly by the Federal Emergency Management Agency (FEMA), the Federal Communications Commission (FCC), and the National Weather Service.

EAS is tested regularly, usually in conjunction with monthly outdoor warning siren tests. In the St. Louis Metropolitan Area, the primary EAS radio stations responsible for activating the EAS are KMOX (1120 AM) and WSDZ (1260 AM).

NOAA Weather Radio (NWR)
A National Oceanic and Atmospheric Administration (NOAA) Weather Radio is also referred to as "the Voice of the National Weather Service" and coverage extends to virtually all parts of the United States. Known primarily for weather alerts, a NOAA Weather Radio may also be used to signal non-weather related local and civil emergencies. Because of this alerting network, emergency managers and public safety agencies encourage all homes and businesses to obtain NOAA Weather Radios.

NWR is made up of a network of more than 970 transmitters across the United States that are directly linked to local National Weather Service offices, which issue weather warnings, as well as relaying other emergency messages on behalf of public safety agencies and alerting authorities. NOAA Weather Radio is provided as a public service by the National Oceanic and Atmospheric Administration.

Weekly tests of the NOAA Weather Radio system are performed. In the St. Louis Metropolitan Area, the primary NWR transmitter is issued via KDO89.

Wireless Emergency Alerts (WEA)
Wireless Emergency Alerts are emergency messages sent by authorized alerting authorities directly to cell phones, through mobile service providers. The messages are very short (currently no more than 90 characters) and are designed to bring critical situations to the public's attention. It will not include all details that are typically provided through other alert methods, but it will alert all phones in the area of the hazard at that time, regardless of where the individual actually resides.

There is no need to subscribe to or download an app to receive a WEA message. The service is provided by the cellular service carrier to alert-capable models of phones. Citizens should check with their cellular phone service provider to discover if their particular phones are alert-capable models.

Integrated Public Alert and Warning System (IPAWS)
The Integrated Public Alert and Warning System may be used by public safety and alerting authorities to send emergency alerts through many methods at one time, to reach as many people as quickly as possible. IPAWS includes texts, email, broadcast radio/TV media and NOAA Weather Radio communication. Some systems also include voice message and outdoor warning siren capabilities. In the future, the system will be adaptable to new technology as it is developed.

St. Charles County Emergency Management has completed Federal and state approval to alert through IPAWS. The system is undergoing final testing before it becomes fully operational to the public.

Outdoor Warning Sirens (OWS)
Outdoor warning sirens are very familiar to most residents and can be seen in virtually every neighborhood in our county. This network of warning sirens is installed and maintained by a cooperative agreement between St. Charles County and municipal authorities. This system is tested regularly.