Flood Warning Issued for Monroe County, IL and Jefferson County, MO
This alert is no longer in effect.
NOAA issued it on May 10, 2026, 3 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.
The National Weather Service has issued a Flood Warning for Monroe County in Illinois and Jefferson County in Missouri, with minor flooding expected along the Mississippi River from Wednesday afternoon to Monday morning.
Read this weather record in 30 seconds
- Record type
- Flood Warning
- Affected area
- Southwestern Illinois and Eastern Missouri
- Issued
- May 10, 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 3 months ago; use the issuing agency's live warning service for current conditions in Southwestern Illinois and Eastern Missouri.
Alert Details
A Flood Warning has been issued by the National Weather Service in St Louis, MO. It is effective starting April 28, 2026.
Affected Areas
The warning affects Monroe, IL and Jefferson, MO, specifically along the Mississippi River near Herculaneum, at Alton, and at St. Louis.
What You Should Do
Turn around and do not drive through flooded roads. Be especially cautious at night when it is harder to recognize the dangers of flooding.
Expected Conditions
Minor flooding is forecast, with the river expected to rise above the flood stage of 26.0 feet to a crest of 28.4 feet.
Timeline
The warning is effective from April 29, 2026, at 15:34 CDT, and ends on May 4, 2026, at 10:00 CDT.
Original source: NOAA Official Notice ↗
Related Weather Alerts
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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 (713 characters here).
Similar severity timing
Same severity (high) notices issued closest in time to May 10, 2026.
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