Flood Warning issued for Cass, Fulton, Mason Counties in Illinois

Source: NOAA · Central Illinois

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A Flood Warning remains in effect for the Illinois River at Havana affecting Cass, Fulton and Mason Counties until August 28 at 10:00AM CDT.

Read this weather record in 30 seconds

Record type
Flood Warning
Affected area
Central Illinois
Issued
August 23, 2026
Issuing authority
NWS Lincoln IL

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: publication date is recent, but current status is not stored on this page. Check the issuing agency's live warning service before acting because warnings can be updated, narrowed, or cancelled.

Alert Details

Flood Warning issued by NWS Lincoln IL. Effective from August 23 at 10:41AM CDT until August 28 at 10:00AM CDT.

Affected Areas

Cass County, IL; Fulton County, IL; Mason County, IL. Specifically the Illinois River at Havana.

What You Should Do

Persons with interests along this river need to remain aware of the latest forecasts and associated flood risk for their area. Stay tuned for further updates on this flooding situation.

Expected Conditions

Minor flooding is occurring and minor flooding is forecast. At 9:45 AM CDT the stage was 16.2 feet. Flood stage is 14.0 feet. The maximum river stage in the 24 hours ending at 9:45 AM CDT was 16.5 feet.

Timeline

The warning is effective until Friday morning, with the river expected to fall below flood stage early Friday morning and continue falling to 12.5 feet by Sunday, August 30.

Original source: NOAA Official Notice ↗

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Nationwide notices with similar length or severity timing 8

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Frequently Asked Questions

Common questions about this NWS weather alert.

What is this NWS weather alert about?
A Flood Warning remains in effect for the Illinois River at Havana affecting Cass, Fulton and Mason Counties until August 28 at 10:00AM CDT.
Which agency issued this alert?
This alert was issued by NOAA. The original notice is available at the source link at the bottom of this article.
How severe is this alert?
This alert is classified as "high" severity. Take precautions and monitor for updates.
What area is affected?
This alert affects Central Illinois. Check with NOAA for the most current geographic scope.
Where can I find more Weather Alerts updates?
Browse the full Weather Alerts feed on Areazine at areazine.com/weather/ for the latest updates from NOAA and other agencies.