Flash Flood Warning Issued for St. Louis Area Until 9 PM CDT
This alert is no longer in effect.
NOAA issued it on May 29, 2026, 2 months ago. Warnings of this kind stay in effect for hours to a few days, so this page is a historical record of what was issued, not a current warning. For conditions where you are right now, check weather.gov (US), weather.gc.ca (Canada), the Met Office (UK), or the Bureau of Meteorology (Australia).
Areazine synthesizes this NWS weather alert directly from NOAA's official public data feed. See our methodology for full source attribution and refresh cadence.
NWS St. Louis has issued a Flash Flood Warning for multiple counties in southwestern Illinois and eastern Missouri effective until 9:00 PM CDT May 18.
Read this weather record in 30 seconds
- Record type
- Flash Flood Warning
- Affected area
- Southwestern Illinois and Eastern Missouri
- Issued
- May 29, 2026
- Issuing authority
- NWS St Louis MO
Flood notices turn on location and timing. Treat the named area as this record's scope; do not assume nearby counties, parishes, or waterways were included.
Record status: historical. It was issued 2 months ago; use the issuing agency's live warning service for current conditions in Southwestern Illinois and Eastern Missouri.
Alert Details
A Flash Flood Warning has been issued by the National Weather Service in St. Louis MO. The alert is effective from May 18 at 5:06 PM CDT until May 18 at 9:00 PM CDT.
Affected Areas
The warning covers Western Clinton County, Southern Madison County, Northwestern Monroe County, and Saint Clair County in Illinois, as well as Northeastern Jefferson County, Eastern Saint Louis County, and East Central Saint Louis City in Missouri. Locations that will experience flash flooding include Belleville, Granite City, O'Fallon, East St. Louis, Collinsville, Edwardsville, Fairview Heights, Cahokia, Swansea, Glen Carbon, Shiloh, Highland, Troy, Waterloo, Columbia, Maryville, Mascoutah, Pontoon Beach, and Centreville. It also includes Frank Holten State Park, Horseshoe Lake State Park, Interstate 64 in Illinois between exits 9 and 27, and Interstate 70 in Illinois between exits 21 and 30.
What You Should Do
Turn around, don't drown when encountering flooded roads. Most flood deaths occur in vehicles.
Expected Conditions
Doppler radar indicated thunderstorms producing heavy rain across the warned area. Between 1 and 2 inches of rain have fallen, with additional rainfall amounts of 1 to 2 inches possible. Flash flooding is ongoing or expected to begin shortly.
Timeline
The Flash Flood Warning is in effect from May 18 at 5:06 PM CDT until May 18 at 9:00 PM CDT.
Original source: NOAA Official Notice ↗
Related Weather Alerts
All Weather Alerts →Nationwide notices with similar length or severity timing 8
Two Areazine-derived peer sets for this NWS weather alert: nearest notices by body length and by same severity near the same agency date. Peers come from other categories so they are not the same-feed Related list above.
Similar body length
Nearest notices by article body length (1,396 characters here).
Similar severity timing
Same severity (high) notices issued closest in time to May 29, 2026.
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Common questions about this NWS weather alert.