Flood Warning Issued for Big River at Byrnesville in Jefferson County
This alert is no longer in effect.
NOAA issued it on April 6, 2026, 5 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 the Big River at Byrnesville, forecasting moderate flooding with a crest of 21.5 feet expected Saturday morning.
Read this weather record in 30 seconds
- Record type
- Flood Warning
- Affected area
- Jefferson, MO
- Issued
- April 6, 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 5 months ago; use the issuing agency's live warning service for current conditions in Jefferson, MO.
Alert Details
The National Weather Service in St Louis MO has issued a Flood Warning for the Big River at Byrnesville. This alert was issued on March 5 at 9:41 AM CST and remains in effect until early Monday morning, March 9. The warning is classified as a severe event with likely certainty.
Affected Areas
The warning specifically impacts the Big River at Byrnesville, located within Jefferson County, Missouri (MOC099).
What You Should Do
Residents and motorists are advised to "Turn around, don't drown" when encountering flooded roads. Most flood-related deaths occur in vehicles. The National Weather Service recommends avoiding flooded areas and monitoring local stream information via official channels.
Expected Conditions
Moderate flooding is currently forecast for the region. As of 8:45 AM CST on Thursday, the river stage was recorded at 8.1 feet. The river is expected to rise above the flood stage of 16.0 feet late this evening. It is projected to crest near 21.5 feet on Saturday morning. For context, at a level of 22.4 feet, Twin Rivers Bridge Road must be closed.
Timeline
The Flood Warning is effective starting late this evening, March 5, 2026. The river is expected to remain above flood stage until late Sunday night, with the warning officially set to expire at 1:00 AM CDT on Monday, March 9.
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 (1,342 characters here).
Similar severity timing
Same severity (high) notices issued closest in time to April 6, 2026.
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