Why sirens kept going off after Franklin County’s tornado warning was over

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COLUMBUS, Ohio ( WCMH ) — As a tornado warning for Franklin County ended last night, sirens warning residents continued to blare in certain areas around Columbus.

Multiple central Ohio counties, including Franklin, Delaware and Licking, went under tornado warnings over the course of the evening. As of Wednesday afternoon, the National Weather Service had confirmed four tornadoes in three Ohio counties, but none that touched down near the Columbus metro.

But 15 minutes after the tornado warning for the area expired, some residents in areas including Westerville, Gahanna and New Albany reported hearing tornado sirens. While the warning was over, the area was still experiencing a severe storm.

NBC4 reached out to the Franklin County Emergency Management team to learn more about the siren activity, and Public Information Officer Kelly McGuire gave this explanation. She named four geographical areas — northwest, northeast, southwest and southeast zones — where the team splits its sirens that can be activated.

“These four zones allow siren activations to more closely align with the warning polygons issued by NWS or the actual location of tornadic activity in Franklin County,” McGuire said.

McGuire also noted that when emergency management turns the sirens on, they don’t continuously sound off.

“Once activated, the outdoor warning sirens will sound with a tone for 3 minutes, followed by 7 minutes of silence,” McGuire said. “This sequence will continue until the warning is canceled.”

In Tuesday night’s case, McGuire said that it was a tornado warning next door that kept sirens on for portions of Franklin County.

“As the population increases, many jurisdictions in Franklin County are expanding into adjacent counties. To ensure the safety of their residents, many jurisdictions have tornado sirens outside of the boundaries of Franklin County on the Franklin County Siren System,” she said. “Although the tornado warning was canceled for Franklin County last night, an active tornado warning continued for New Albany in Licking County which triggered the sirens to remain active in the northeast zone until they were manually canceled.”

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