When Johnson County tested its outdoor warning system last week as part of National Severe Weather week, about 15 sirens failed to activate when they should have.
Officials with the Johnson County Division of Emergency Management said a software upgrade the week prior is to blame for the sirens’ failure to sound right away using the activation system.
The failure forced Johnson County to use its backup system, according to Johnson County Emergency Coordinator Dave C. Wilson. Technicians believe they have resolved the problem, according to a news release, but the county will resume testing this week to be sure.
Outdoor siren tests normally occur on the first Wednesday of every month, but Johnson County had planned to skip the test this week because of last week’s test. Due to the failure, however, sirens will be tested at 10 a.m. Wednesday, according to the news release.
Tests can be cancelled in extreme weather conditions or if there is severe weather – to avoid confusion between a test and a real emergency.
The outdoor warning system aims to alert the public of a tornado warning, which sounds like a steady tone, or an attack, which sounds like a wavering tone. There are three criteria needed to activate the sirens for tornadoes: the National Weather Service has issued a tornado warning for the area, a county trained and certified weather spotter reports a tornado, or a tornado is reported by a local public safety official.
Johnson County can activate all of the sirens at once or just the sirens in one or more of the five siren zones.