Update — November 8, 2026:

The National Weather Service’s Sunday forecast keeps the Iowa River at Marengo near 15.5 feet through early Monday morning, November 9, and now expects it to fall below flood stage early Monday evening. That is later than the early-Monday-afternoon crossing forecast retained below.

The gauge measured 15.5 feet at 9 a.m. CST Sunday, half a foot above the 15-foot flood stage. The 9:22 a.m. bulletin describes minor flooding and extends the warning until Monday evening. At the 15-foot impact threshold, water reaches the bottom of the levee surrounding Marengo and affects low-lying agricultural land along the river.

Motorists should avoid flooded roads and barricades, and people walking near riverbanks should use caution, the agency advises. This update concerns Marengo; the earlier North Skunk and Missouri forecasts below retain their original dates and should not be read as new Sunday observations.

Earlier Reporting:

Update — November 7, 2026, 10:07 p.m. Central:

The National Weather Service revised the flood warning for the Iowa River at Marengo to run through 6:30 p.m. CST Monday, November 9, earlier than the 10 p.m. end time in its morning bulletin.

The river remained at 15.4 feet at 8 p.m. Saturday, above its 15-foot flood stage. Forecasters continued to expect a crest near 15.6 feet Sunday afternoon and a fall below flood stage early Monday afternoon. The new bulletin changes the warning’s stated duration; it does not report a higher Marengo crest forecast.

A separate warning for the North Skunk River near Sigourney, Iowa, was extended through 11:25 p.m. Sunday, November 8. The river stood at 16.9 feet at 8:30 p.m. Saturday, above its 16-foot flood stage. It was forecast to crest around 17 feet Saturday night and fall below flood stage Sunday afternoon.

The agency describes minor flooding at both locations. Its Sigourney impact threshold identifies agricultural land, some county roads and farmhouses as vulnerable at 16 feet. Motorists are advised against driving around barricades or through flooded areas.

The two notices were issued at 9:24 p.m. CST November 7. The Missouri information below is historical and has not been reclassified as current.

Earlier Reporting and Forecast History:

Update — November 7, 2026, 12:02 p.m. Central:

Minor flooding is occurring on the Iowa River at Marengo, Iowa, according to a Saturday morning National Weather Service statement. The river stood at 15.4 feet at 9 a.m. Central Standard Time, above the 15-foot flood stage.

The revised forecast calls for a crest of 15.6 feet early Sunday afternoon, November 8, followed by a fall below flood stage early Monday afternoon. The warning continues until 10 p.m. CST Monday, November 9.

At the 15-foot impact threshold, water reaches the bottom of the levee surrounding Marengo and affects low-lying agricultural land. The agency advises against driving around barricades or through flooded areas and urges caution near riverbanks.

This update concerns the Iowa River at Marengo. The November 3 Platte River forecast retained below is historical and does not establish current Missouri conditions.

Earlier Reporting — November 3 Forecasts:

The National Weather Service issued new flood warnings Tuesday for the Iowa River at Marengo, Iowa, and the Platte River near Agency, Missouri, as both waterways were forecast to rise above flood stage.

At Marengo, the Iowa River stood at 12.4 feet at 10 a.m. CST. Forecasters expect it to cross the 15-foot flood stage late Tuesday night and crest near 16.5 feet Friday evening.

The warning for Marengo remains in effect from late Tuesday night until further notice. At 16 feet, water begins affecting agricultural land along the river and can be several feet deep in low-lying areas.

The Weather Service urged motorists not to drive around barricades or through flooded roads and advised people to use caution near riverbanks.

Near Agency, Missouri, the Platte River stood at 12.5 feet at 8:30 a.m. CST. Forecasters expect it to rise above its 20-foot flood stage Wednesday afternoon and crest near 24.8 feet Thursday evening.

That warning covers Buchanan County and remains in effect from Wednesday afternoon through Saturday evening. At 20 feet, low-lying areas east of Agency begin to flood. The river is forecast to fall below flood stage late Friday evening.

Both warnings describe forecast minor flooding, but the expected rises can still affect roads, farms and low areas near the rivers. The warnings are based on river-gauge observations and forecasts and may be updated as new measurements arrive.

Marengo is in eastern Iowa, roughly 30 miles west of Iowa City. Agency is in northwestern Missouri, south of St. Joseph. Residents and travelers near either river should use local road-closure information and updated Weather Service statements before approaching low crossings.

The latest warning times and crest forecasts were issued Tuesday morning. Conditions can change before the rivers reach their projected peaks.

Sources: - National Weather Service Quad Cities, Iowa River flood warning, Nov. 3, 2026 - National Weather Service Kansas City/Pleasant Hill, Platte River flood warning, Nov. 3, 2026 NWS Quad Cities — November 7 Marengo warning: https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.3bebdfd9653a3f61a32caed1d7f3458147c179a1.002.1 NWS Quad Cities — November 7, 9:24 p.m. Sigourney warning: https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.f8272784b0178f0d907bc159a759599abae66e35.001.1 NWS Quad Cities — November 7, 9:24 p.m. Marengo warning: https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.f8272784b0178f0d907bc159a759599abae66e35.002.1