COLUMBIA, Mo. (April 27, 2026) - Boone County Emergency Management staff were monitoring severe weather throughout the evening of April 26, 2026, when outdoor warning sirens were activated in response to a severe thunderstorm capable of producing tornadoes and expected to impact southern Boone County.

The outdoor warning sirens sounded twice — at 8:44 p.m. and 8:58 p.m. The repeated activations reflected the continuation of tornado warning coverage and ongoing storm movement through the area.

Boone County uses an automated system called CommanderOne as the primary means of activating the siren system, which allows sirens to activate only in areas directly impacted by NWS polygons. Staff remain available to activate the sirens manually should that be needed.

Sirens activate under two conditions:

• Tornado Warnings issued by the NWS for affected portions of Boone County
• Severe Thunderstorm Warnings with a “Destructive” damage threat tag, indicating winds of at least 80 mph or hail 2.75 inches or greater

Outdoor warning sirens are intended to alert people who are outside to seek shelter immediately. They are not designed to be heard indoors and should not be the only source of weather alerts. Residents should have multiple ways to receive warnings, including wireless emergency alerts, NOAA Weather Radio, local broadcasts, and trusted weather apps.

If a tornado warning is issued, move immediately to an interior room on the lowest level of a sturdy building, away from windows.

For updates on storm response and recovery efforts, follow the Boone County Office of Emergency Management at www.boonemo.gov/oem/, and on social media channels.

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