During regularly scheduled testing on Wednesday, the Clermont County outdoor warning siren system malfunctioned, according to county communications coordinator Mike Boehmer.
Boehmer said the malfunction was caused by a lightning strike. The system failure happened county-wide, affecting all 19 sirens throughout the region.
Stephanie Porter, who lives within 100 feet of one siren, said she noticed the silence Wednesday at noon.
"It's loud, but we've grown used to it," Porter said. "I hope they fix it. It would've been nice to be notified that they aren't working."
The county's siren contractor came in and fixed the issue within a few hours, but it's not the first time a Tri-State county's siren system has failed.
Clinton County's emergency management director confirmed in March the county's 27 outdoor sirens failed due to a malfunction. That failure happened when it was needed the most — when the county tried to warn residents of an approaching EF0 tornado.
"Well we need it fixed," resident Martin Barton said at the time. "We need that because if you're away from your phone, you're going to be in trouble."
Clermont County's warning system will be tested at noon on Thursday, while Clinton County is set for a test Friday at noon.
The tests will happen before some areas of the Tri-State could experience severe thunderstorms, though Northern Kentucky is currently poised for the highest risk.
Officials said they will continue to work quickly to keep people safe.
Clinton County officials confirm sirens failed when EF0 tornado touched down
MAP: A look at all the tornadoes that have touched down in the Tri-State since 1950