Residents across the Midwest and Plains states surveyed damaged homes for salvageable items Sunday, after more than 100 tornadoes were reported in the region earlier, killing at least 5 in Oklahoma -- including three children.
Emergency crews, meanwhile, were trying to repair downed power lines.
A tornado hit just after midnight Sunday in Woodward, Okla., about 140 miles northwest of Oklahoma City. City Manager Alan Riffel says 89 homes and 13 businesses were destroyed.
State medical examiner spokeswoman Amy Elliot says a man named Frank Hobie and his two daughters, ages 5 and 7, died after the tornado hit their mobile home park.
She says the other victims were Darren Juul and a 10-year-old girl who died when the home they were in a few miles away was hit.
The men's ages and the children's names haven't been released.
Elliot says a critically injured child was air lifted to a Texas hospital.
Retired firefighter Marty Logan said he spotted the tornado when it knocked down power lines, causing flashes of light, and saw a radio tower's blinking lights go black shortly after midnight. He later saw a man emerge from a twisted, wrecked sport utility vehicle that had been tossed along the side of the road.
"The guy had blood coming down his face," Logan said, adding that he saw people walking down the street covered in blood when he went to a hard-hit neighborhood. "It was scary, because I knew it was after midnight and a lot of people were in bed."
Search teams were scouring rubble for trapped and injured as the sun came up.
"They're still going door to door and in some cases, there are piles of rubble and they are having to sift through the rubble," said Michelann Ooten, an Oklahoma emergency management official.
The National Weather Service said the storm systems were weakening and that additional tornadoes were unlikely. But forecasters warned that strong thunderstorms were expected as far east as Michigan.
In the tiny western Iowa town of Thurman, piles of toppled trees lined the streets in front of homes where missing walls and roofs exposed soaked living rooms. Longtime resident Ted Stafford recalled feeling his home shake, then hearing three windows shatter as the storm hit. He said he was amazed that no one in town was seriously injured.
"We're all OK, fortunately. Nobody's hurt. We can fuel this recovery with beans and coffee," the 54-year-old said while standing on the broken concrete of what had been his home's new basement foundation. "I've seen storms in Thurman. I've lived here my whole life. And this is by far the worst I've ever seen."
The storms were part of an exceptionally strong system that the Storm Prediction Center in Norman, Oklahoma, which specializes in tornado forecasting, had warned about for days.
The center took the unusual step of warning people more than 24 hours in advance of a possible "high-end, life-threatening event." Forecasters had worried the storms would hit overnight, when people are less likely to hear warning sirens and pay attention to weather reports.
At the storm's height, tornadoes popped up faster than they could be tallied. The center's spokesman, Chris Vaccaro, said the weather service had received at least 120 reports of tornadoes by dawn Sunday.
He warned the threat wasn't over for those across several states in the nation's interior. Forecasters predicted the possibility for storms Sunday in a swath that stretched from southern Texas to northern Michigan.
The American Red Cross summoned volunteers to drive relief trucks from Oklahoma City to aid the rescue crews in and around Woodward he said were pressed to the limit by the immediate disaster response.
"They're in chaos mode," said Rusty Surette, a regional communications director for the American Red Cross in Oklahoma City, speaking of authorities in Woodward.
Numerous tornadoes were reported in Kansas, though mostly in rural parts of the western and central sections of the state.
A reported tornado in Wichita that struck late Saturday night caused damage at McConnell Air Force Base and the Spirit AeroSystems and Boeing plants. A mobile home park was heavily damaged in the city, although no injuries or deaths were reported.
The county where Wichita is located was declared a state of disaster and said preliminary estimates suggest damages could be as high as $283 million.
A hospital in Creston, about 75 miles southwest of Des Moines, suffered roof damage and had some of its windows blown out by the storm, but patients and staff were not hurt. Medical center officials were calling other area hospitals to determine how many beds they had available in case they needed to move patients.
In Nebraska, large hail shattered windows and tore siding from houses in and around Petersburg, about 140 miles northwest of Omaha. In southeast Nebraska, an apparent tornado took down barns, large trees and some small rural structures.
The Associated Press contributed to this report.