Residents in Kansas and Missouri were steeling themselves Monday for the deadly and “unprecedented” flooding that's already saturated large portions of the Midwest, mangling hundreds of homes and raising the Missouri River above record water levels in many areas.

In Atchison, Kansas, a city with a population of more than 10,000, businesses are reported to be piling up sandbags as the National Weather Service is forecasting river levels to reach 30 feet there later this week – something likely to prompt major flooding.

“It’s not looking good at all,” Sara Tull, a local resident, told KCTV. “I think it’s [going to] get us this time and I hate to say that.”

People view the rising waters from the Platte and Missouri rivers which flooded areas of Plattsmouth, Neb., on Sunday.

NEBRASKA FARMER WHO DIED TRYING TO RESCUE A STRANGER FROM FLOODWATERS IS HAILED AS A HERO

Some of the city’s residents have already left for higher ground. Other communities in states like Nebraska are still reeling Monday from floods that swept through the region in recent days. And serious flooding is expected to continue there over the next few days, despite river depths leveling off in some parts, the Associated Press is reporting.

"This area's had flooding before but not of this magnitude," said Greg London of the Sarpy County Sheriff's Office, where 500 homes are estimated to be damaged. "This is unprecedented."

The damage in Sarpy County followed breaches of levees along the Platte River on Thursday and Saturday, and a Missouri River levee break on Thursday. The two rivers converge there.

In Iowa, the Missouri River reached 30.2 feet Sunday in Fremont County in the state's far southwestern corner, two feet above the record set in 2011. Around 250 people in the towns of Bartlett and Thurman were being evacuated as levees were breached and overtopped.

Gabe Schmidt, owner of Liquid Trucking, back right, travels by air boat with Glenn Wyles, top left, Mitch Snyder, bottom right, and Juan Jacobo, bottom left, as they survey damage from the flood waters of the Platte River, in Plattsmouth, Neb., on Sunday.

County Emergency Management Director Mike Crecelius said it wasn't just the amount of the water, it was the swiftness of the current that created a danger.

"This wasn't a gradual rise," Crecelius said. "It's flowing fast and it's open country — there's nothing there to slow it down."

EXTREME FLOODING HINDERS RESCUES ACROSS MIDWEST

Lucinda Parker of Iowa Homeland Security & Emergency Management told the Associated Press that nearly 2,000 people overall have been evacuated at eight Iowa locations since flooding began late last week.

The floods were prompted by a late-season “bomb cyclone” that brought heavy rains and eventual snowmelt to the Midwest.

Hundreds of people also remain out of their homes in Nebraska, where floodwaters reached record levels at 17 locations.

The Missouri River has flooded Offutt Air Force Base, with about one-third of it underwater on Sunday. Spokeswoman Tech. Sgt. Rachelle Blake told the Omaha World-Herald that 60 buildings, mostly on the south end of the base, have been damaged, including about 30 completely inundated with as much as 8 feet of water.

At least two Nebraskans have died in the floodwaters while nearly 300 more have been rescued.

Aleido Rojas Galan, 52, of Norfolk, was swept away Friday night in southwestern Iowa, when the vehicle he was in went around a barricade. Two others in the vehicle survived — one by clinging to a tree. On Thursday, Nebraska farmer James Wilke, 50, died when a bridge collapsed as he used a tractor to try and reach stranded motorists.

Two men remained missing Monday. A Norfolk man was seen on top of his flooded car late Thursday before being swept away. Water also swept away a man after a dam collapse.

Downstream in St. Joseph, Missouri, home to 76,000 people, volunteers are helping to fill sandbags to help secure a levee protecting an industrial area. Calls were out for even more volunteers in hopes of filling 150,000 sandbags by Tuesday, when the Missouri River is expected to climb to 27 feet — 10 feet above technical flood stage.

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The rising Mississippi River also was creating concern. The Mississippi was already at major flood level along the Iowa-Illinois border, closing roads and highways and swamping thousands of acres of farmland. Moderate Mississippi River flooding was expected at several Missouri cities, including St. Louis.

Flooding has also been reported in Minnesota, South Dakota and Wisconsin. In Green Bay, Wisconsin, officials said residents who evacuated their homes could return now that floodwaters have receded there.

The Associated Press contributed to this report.