⚠️ Severe Thunderstorm Warning – Monroe, IL; Jefferson, MO – Sunday, September 20, 2026

Severe Thunderstorm Warning issued September 20 at 10:47PM CDT until September 20 at 11:30PM CDT by NWS St Louis MO

Details

SVRLSX

The National Weather Service in St Louis has issued a

* Severe Thunderstorm Warning for…
Northwestern Monroe County in southwestern Illinois…
Northeastern Jefferson County in east central Missouri…

* Until 1130 PM CDT.

* At 1047 PM CDT, a severe thunderstorm was located over Horine, or
over Pevely, moving east at 20 mph.

HAZARD…60 mph wind gusts and quarter size hail.

SOURCE…Radar indicated.

IMPACT…Hail damage to vehicles is expected. Expect wind damage to
roofs, siding, and trees.

* Locations impacted include…
Festus, Antonia, Horine, Crystal City, Pevely, Herculaneum,
Barnhart, Imperial, Harrisonville, Kimmswick, Valmeyer, Monroe
City, Fountain, Madonnaville, Maeystown, Foster Pond, Waterloo and
Columbia.

This includes the following State Parks…
Illinois Caverns State Natural Area, Mastodon Historic Site and Gov.
Dunklin’s Grave Historic Site.

This includes Interstate 55 in Missouri between exits 175 and 187.

Instructions

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

This alert was automatically posted by SkyGuard, MWSC’s severe weather alerting system. Source: National Weather Service.