O’FALLON, Ill. – Fifteen sirens were activated, alerting about 40,000 residents in the Metro East after the National Weather Service issued a severe thunderstorm warning at 8:15 p.m. Sunday. The warning forecasted straight-line winds of 58 miles per hour.
The sirens are activated from inside the Metro East Communications Center, which is located in the O’Fallon Public Safety building. The sirens cover three communities: O’Fallon, Shiloh, and Fairview Heights.
The center also gets its weather information from a private firm, Weather Sentry, which forecasted the same threat.
Based on those two sources, O’Fallon sounded the sirens.
The National Weather Service said most counties and local governments activate the sirens only for a tornado warning. But Daryl Ostendorf, support services supervisor for the Metro East Communications Center, said they take a proactive approach with the threat of damaging winds
"When these flat-line winds these damaging winds are coming essentially what we're trying to do is tell people to take shelter when that goes on. Same with tornado winds,” he said. “So, damaging winds of 58 miles per hour or greater can rip off your siding, tear the roof, the top of trees, and knock down power lines, so we want them to go in and take shelter."
Ostendorf said a wide variety of weather variables make it impossible to detect an exact set of conditions so they will always err on the side of caution when making the decision to activate an alert.