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Warning System Alerts Residents in San Marcos

SAN MARCOS, TX – Unlike hurricanes, which can be tracked prior to landfall, the art of tornado predictions is still in its infancy. Tornadoes can strike with only minutes to prepare and the consequences to life and property can be significant.

Evidence consistently shows that an investment in early warning systems can save lives. With this in mind, the city of San Marcos, Texas, wanted a way to communicate impending dangers if a tornado was spotted. The result was an early warning siren system installed to alert the public, allowing them the opportunity to move indoors quickly.

The warning system consists of 14 outdoor sirens located throughout the city. The sirens can be activated individually, but in most cases they are activated simultaneously for a city-wide emergency. In the event of a tornado, the system sends three to five minute steady signals. The siren tone is similar to firetruck sirens.

“The entire city can hear the sirens when they are activated,” said Kenneth Bell, Emergency Management Coordinator for San Marcos.

The city received a $262,500 grant from the Federal Emergency Management Agency Hazard Mitigation Grant Program (HMGP) to purchase the warning system. HMGP paid 75 percent of the cost of this approved project. The remaining 25 percent was paid for with city funds. The total cost of the system was $327,750.

The most noticeable feature of the stand-alone unit system is its prominent position on top of poles. Another feature is that the units are connected into electrical grids that have backup power in case the electricity goes out. During a power failure, the sirens automatically switch to rechargeable batteries. The sirens can be remotely activated by radio and the radios are capable of running the sirens through different signals.

Audible siren testing is performed monthly to ensure the system is fully operational. “If the weather is bad or threatening we do not test the system,” said Bell. “This helps to ensure that there is no confusion as to whether it is a test or a real alert.”

The warning system was installed in 2012 and had its first test on Memorial Day weekend, May 25, 2015. During this historic event, the city was severely impacted by record flooding and, at the same time, tornadoes were spotted. The tornado sirens sounded to alert the public to stay indoors and shelter-in-place.

The sophisticated warning system, which often works in conjunction with targeted text messages and announcements, is activated when:

The National Weather System issues a San Marcos-area tornado warning or severe thunderstorm warning with destructive winds at or above 70 mph.

Trained storm spotters have reported a tornado with the potential to affect the city of San Marcos.

Hail of 1.25 inch (half dollar) in diameter is imminent.

Deemed necessary by the city of San Marcos officials (i.e., in the event of any emergency when officials need to get citizens to move indoors for their safety.

For additional information on Community Warning Systems, visit: Alerts & Warning Systems.

Last updated June 3, 2020