OKLAHOMA CITY (Reuters) - Rescue and clean-up efforts were underway across the Midwest on Sunday after dozens of tornados tore through the region, killing at least five people in Oklahoma, leaving thousands without power in Kansas and damaging up to 90 percent of the homes and buildings in one small Iowa town.
Storms skipped across what is often called "Tornado Alley" in the U.S. Central and Southern Plains, but the high winds and dozens of tornados mostly struck rural areas, sparing the region from even worse damage.
The stormy weekend isn't over yet for the Midwest - there is a moderate risk of more "significant" tornadoes later Sunday afternoon from southeast Minnesota through a large part of Wisconsin and northeast Iowa, according to National Storm Prediction Center meteorologist Greg Dial.
Damaging thunderstorms are also predicted from Minnesota south to Texas into Sunday night, according to AccuWeather.com.
Earlier Sunday, a twister struck the northwest Oklahoma city of Woodward, where storm sirens failed to sound after lightning apparently disabled its warning system, Mayor Roscoe Hill said.
A total of 29 people were treated at Woodward Regional Hospital, chief executive officer Dave Wallace said. Of these, five were in critical condition and moved to other hospitals.
Two children died at a mobile home park in Woodward, a town of 12,000 people, while two adults were killed in a small community just outside the city limits, Hill said. Details of the fifth death were not immediately known, said Keli Cain, spokeswoman for Oklahoma Emergency Management.
"This thing took us by surprise," Hill said. "It's kind of overwhelming."
Woodward city manager Alan Riffel told CNN that all the missing people had been accounted for, and that 89 homes and 13 businesses had been destroyed.
A tornado that struck Woodward in April 1947 still ranks as the deadliest in Oklahoma history, with 116 people killed, according to the National Weather Service.
In tiny Thurman, Iowa, population 250, an estimated 75 to 90 percent of the town's buildings and homes were damaged or destroyed by the storm, Freemont County Emergency Management Coordinator Mike Crecelius said. Only minor injuries were reported.
The National Storm Prediction Center had an unofficial count of 98 tornadoes in Nebraska, Iowa, Kansas and Oklahoma, starting Saturday morning and going until early Sunday.
In Kansas, Governor Sam Brownback declared a state of emergency as officials assessed storm damage.
No deaths or serious injuries were reported in Kansas, but about 11,000 people were reported without power, most of them around Wichita, Sharon Watson, a spokesperson for the state's National Guard and emergency services, said in a news release.
The storm damaged a hangar at McConnell Air Force Base in Wichita and destroyed several homes around the area, authorities said.
Storm chaser Brandon Redmond, a meteorologist with the Severe Weather Alert Team, said the twister passed over his vehicle and lifted it 2 feet (60 cm) off the ground in an industrial area south of Wichita, the state's second-largest metropolitan area after the Kansas City metro area.
"The tornado literally formed over our vehicle," he told Reuters. "I've never been that scared in my life. ... We had power flashes all around us and debris circulating all around the vehicle, sheet metal, parts of a roof, plywood."
Sedgwick County Commission Chairman Tim Norton said the tornado missed downtown Wichita and heavily populated neighborhoods and passed through areas to the south and east where there are manufacturing businesses and mobile home parks.
"With the storms we saw coming our way, it could have been much worse," Norton said. "We lucked out."
The damage included a Spirit Aerosystems (SPR.N) production facility that manufactures fuselages for Boeing's 7-series airplanes. A Spirit spokesman said the facility was shut down on Sunday after a tornado damaged the roof and knocked out power, but the company hoped to have the plant running again soon.
"We do believe that the majority of the operational capabilities and facilities are intact," spokesman Ken Evans said.
A Boeing spokesman (BA.N) said the company had been in touch with Spirit to assess the situation.
The U.S. tornado season started early this year, with twisters already blamed for 62 deaths in 2012 in the Midwest and South, raising concerns that this year would be a repeat of 2011, the deadliest tornado year in nearly a century.
Some 550 people died in tornadoes last year, including 316 killed in an April outbreak in five Southern states, and 161 people in Joplin, Missouri, the following month.
Reporting by Corrie MacLaggan, Mary Wisniewski, Steve Olafson, Kevin Murphy, Dena Aubin and Tim Gaynor; Writing by Cynthia Johnston and Paul Thomasch; Editing by Eric Beech