Severe Weather Siren System
To help you protect your family and loved ones during severe weather conditions, the City of O’Fallon uses an Emergency Alerting System composed of nine (9) sirens strategically located throughout the City. The system is designed to alert residents and visitors of potentially severe weather, including tornado warnings and severe storms with high winds.
Information for the activation of the system can come from several sources including the National Weather Service, St. Clair County, State or Federal Agencies, local Public Officials and/or first hand observation. Most often, the emergency telecommunicators responsible for activating the system rely on teletypes from the National Weather Service and local television and radio weather reports for information regarding storm conditions. As part of a regional program, our sirens are tested the first Tuesday of every month at 10 a.m.
The Emergency Alert system is activated through the O’Fallon Police Department dispatch center when the following conditions are present:
Tornado Warning - A tornado has been visually confirmed and/or a tornado warning has been issued indicating that the City of O’Fallon is in the path of an approaching tornado, conditions of an approaching storm exist for the development of a tornado, or whenever any reported tornado sighting within the City, or nearby community, is confirmed.
High Winds - When it has been confirmed that “Damaging Force” winds will be impacting the City of O’Fallon and/or the National Weather Service has issued a Severe Storm/High Wind Warning indicating damaging force winds. Damaging Force winds are those winds monitored with gusts at 58+ mph.
Activation of the “Emergency Alert System” may be authorized for the previously described public safety threats by any Public Safety employee upon receiving or observing conditions which he/she feels requires the public to be immediately notified of imminent danger. Upon activation of the “Emergency Alert System”, all public safety first responders are notified of the system activation as well as the nature of the threat via a radio/paging system.
The wide variety of variables involved in predicting the weather make it impossible to determine the exact set of conditions necessary for an alert; therefore, we will always error to the side of caution when making the decision to activate the system. That said, we will endeavor to make the most judicious use of the system so that we do not create a climate of complacency.
O’Fallon’s sirens are located
in the following areas:
Bethel School Road
Braeswood Subdivision
Central School
Delores Moye School
Edward Fulton Jr. High School
Estelle Kampmeyer School
Green Mount Road
Milburn School Road
OTHS
When the sirens are activated, residents are encouraged to proceed to an interior room on the lowest level of their home or business and monitor local television, radio, weather alert radio or other source of current weather data for the most up-to-date information. O’Fallon’s system features only one alert signal, a constant siren, and we do not sound an “all clear” alert following system activation.
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