Village Warning Sirens

The outdoor warning sirens are activated from the Village Emergency Services Disaster Agency (ESDA).  The local, state, and national ESDA have a network of trained weather spotters that are activated when severe weather conditions arise.  Spotters are placed in strategic locations that provide open views of the sky, and in conjunction with ground spotters and other emergency resources, communicate with ESDA to report funnel clouds, tornado touchdowns, or other severe weather events.

Typically reports of funnel clouds are verified by a spotter or other creditable agency representative before the sirens are activated. It is important to realize that during a severe weather incident like this, it is typical to get hundreds of reports of funnel clouds all over our county. It is important that these are confirmed, as most of these reports turn out to be negative. If the sirens were activated for any report, you would find that they would be sounding constantly through an entire thunderstorm event. This would make them ineffective as people would simply ignore the warning.

Remember, the outdoor warning sirens are used to alert citizens who are outdoors during the imminent hazard to prompt them to seek shelter and additional information on the threat (timing, location, and severity).

Sirens are recommended to be activated for:

• Tornado Warning - Issued by the National Weather Service
• Tornado or Funnel Cloud indicated on Radar, or reported by a trained spotter (Law Enforcement, Fire Department, or Emergency Management Officials)
• Severe Thunderstorm Warning - Issued by the National Weather Service with Winds 85 mph or greater
• Environmental Disasters (Mass Flooding, Earthquakes, etc.)
• Man-made Disasters (Train Derailment, Chemical Spills, etc.)

The Village Warning Sirens are activated manually by the ESDA Director. 

There is no such thing as an "All Clear" signal from the outdoor warning sirens.  If you are hearing sirens sounding, the threat is happening right now.  People in or near the warned area should then monitor reliable sources such as NOAA All-Hazards Radio or local media services to know when the threat has dissipated.

While you may receive a warning message via various outlets, there might not be an eminent threat to the Village if the warning sirens did not get deployed. You may receive an automatic Wireless Emergency Alert (WEA) on your phone when there is a tornado warning in Champaign County. If Thomasboro is not in the direct path of the confirmed or radar indicated tornado, the sirens likely will not sound. 

Outdoor warning sirens are designed for alerting people outside their homes and away from other media sources of imminent danger from an approaching storm. It is designed to warn these people outside to take cover immediately. The sirens are not designed as a consistent warning system for persons inside of structures.

While sirens may be heard inside, there are a variety of factors that can influence someone's ability to hear the siren, such as topography, obstructions between the siren and the structure, construction of the building or residence, other noise sources (TV, radio, hail, wind, etc.), and/or distance from the siren. The Village has three outdoor warning sirens. The sirens are designed to have a 1.5 mile coverage area based on the decibel level per the manufacturer.  The redundancy of the system allows for outdoor users to hear sirens even when one closer may not sound, but this is also why it may not be heard indoors.

 Individuals are responsible for monitoring conditions for their personal safety. The National Weather Service has created a warning system that consists of Watches and Warnings for a variety of weather conditions to keep people informed. These informational watches and warnings are broadcast over TV and Radio, and are available via the Internet and on Cell Phones. When weather systems approach, people should monitor these devices to keep up to date on the conditions.  

• A Watch (Severe Thunderstorm or Tornado) means that conditions are right for these type of storms to occur. During a watch, people should monitor conditions and be prepared to take shelter. 
•  A Warning means that the severe weather is occurring in the area, people should seek shelter immediately. People should not wait until the sirens are activated, or a tornado is actually sighted in their specific area, as this can be too late. A Warning is the time when people need to be in a protected place monitoring conditions until they improve and the situation passes. 

As with any system, proper testing is essential to ensure that the sirens are functional in an emergency.  In the Village (and in the majority of Illinois municipalities), outdoor warning sirens are tested monthly on the first Tuesday at 10:00am.  If there is inclement weather, the monthly test will be postponed or cancelled. The siren sound is a long steady tone, which is used to alert individuals outside their homes and away from other media sources of imminent danger from severe weather conditions.