Severe Thunderstorm Warning: Seek Shelter Immediately in Monroe, Jefferson

Residents in northwestern Monroe County, Illinois, and northeastern Jefferson County, Missouri, are advised to seek shelter immediately due to a Severe Thunderstorm Warning issued by the National Weather Service in St. Louis. The warning is in effect until 11:30 PM CDT tonight, September 20.

At 10:47 PM CDT, a severe thunderstorm was detected over Horine, or near Pevely, moving east at 20 mph. This storm is capable of producing 60 mph wind gusts and quarter-size hail. The National Weather Service reports that radar indicated these hazards.

Expected impacts include hail damage to vehicles and wind damage to roofs, siding, and trees. Communities within the warned area include Festus, Antonia, Horine, Crystal City, Pevely, Herculaneum, Barnhart, Imperial, Harrisonville, Kimmswick, Valmeyer, Monroe City, Fountain, Madonnaville, Maeystown, Foster Pond, Waterloo, and Columbia. This also includes Illinois Caverns State Natural Area, Mastodon Historic Site, Gov. Dunklin's Grave Historic Site, and Interstate 55 in Missouri between exits 175 and 187.

Seek shelter inside a well-built structure and stay away from windows. This storm is capable of producing damaging winds and large hail.