The emergency is for areas near Valley, west of Omaha, between the Platte and Elkhorn Rivers, after a dam on Union Dike has failed, the National Weather Service said.
The Omaha Valley weather service office said it was evacuating its staff.
"Flooding of Small Creeks and Poor Urban Drainage Spaces" Across the southeast of South Dakota, northeastern Nebraska, and northwest Iowa. Frozen soil and high water levels in the main river systems slowed the decline of floods in many places, "said the National Weather Service.
and) sno By smelting are small streams and streams, urban areas, highways, roads and underpasses as well as other drainage areas and Flooded low-lying areas. "
The Fond du Lac was flooded with ice jams on the River du Lac, meteorologists said, while other affected areas were Lodi in Columbia County, Darlington in Lafayette County, Prairie du Sac in Sauk County and DeForest in Dane County.
"Bomb Cyclone" Moves North to Canada
Dangerous weather conditions were expected for millions of people under surveillance, warning or counseling on their way east and then north.
A bomb cyclone occurs when there is a rapid pressure drop, with a drop of at least 24 millibars – a measure of the atmosphere Pressure – over 24 hours. This storm has cut 33 millibars from Tuesday to Wednesday.
"Although the bomb cyclone was clearly on the blizzard side, the area east of the low took significantly heavy rains above the existing snow cover and non-frozen soil to absorb rain and runoff," said CNN meteorologist Chad Myers.
The heavy rains of the storm resulted in large floods and damaged roads and bridges in Iowa, Nebraska and Missouri.
Nebraska Game and Parks Commission employees launch a fan boat to rescue the inhabitants of Gretna. The Mead Fire Department helped people near Horseshoe Lake. The Columbus Police Department warned residents to stay away from the Black Bridge. It is believed that a person is missing in Boyd County when a dam collapsed and a house was washed downstream.
CNN's Dave Hennen, Monica Garrett, Eliott C. McLaughlin and Nicole Chavez contributed to this report.