FloodZoneMap.org

Flood — Pottawattamie, IA

Aug 1, 2011

A record rain event in May in eastern Montana combined with high water from storms in April and May, plus snow melt from a much above normal snow pack, all contributed to bring record high water to the Missouri River chain of reservoirs by late Spring. Then residual snow melt and additional rains produced record 13.8 million and 10.0 million acre feet of runoff above Sioux City in June and July respectively. This helped contribute and sustain record releases from the Missouri River Reservoirs f

Source: NOAA National Weather Service Storm Events Database (event 322997). Narrative written by NWS staff at the time of the event.

Flood Risk Context for Pottawattamie, IA

This event is one of many recorded floods in Pottawattamie County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.

View Pottawattamie County flood data →

More Flood Stories

Flood$550K damage

Pottawattamie, IA · Jun 24, 2024

A series of shortwave troughs traversing the northern CONUS brought unsettled weather to the area for the end of June. On the 21st, a stationary front was draped across northeast Nebraska into Iowa.

Read the full account →
Flash Flood$75K damage

Pottawattamie, IA · May 21, 2024

Troughing over the western CONUS brought southwesterly flow aloft over the central and northern Plains for the duration of this event. In the couple of days leading up to May 21st, the upper-level flow pattern amplified as a trough deepened over the northern Rockies.

Read the full account →
Flash Flood$5.0M damage

Pottawattamie, IA · Sep 23, 2015

An area of upper level low pressure slowly moved across the central Plains during the September 22nd through the 23rd time frame. Significant moisture was in place across the mid Missouri River Valley ahead of this system.

Read the full account →
Flood$3.0M damage

Pottawattamie, IA · Jul 1, 2011

A record rain event in May in eastern Montana combined with other storms in April and May plus early spring snow melt and brought record high water to the Missouri River chain of reservoirs.

Read the full account →