A father and his two young daughters were among six killed when dozens of tornadoes ripped across the Central and Southern Plains in the early hours of Sunday.
Relatives told NBC affiliate KFOR TV that Frank Hobbie and his daughters, Faith, 5, and Kelley, 7, were killed when a powerful tornado destroyed their mobile home park in Woodward, Okla.
“They were grandma and grandpa’s girls and it’s just going to be hard without them and their daddy; he was a good daddy,” said Shelly Hobbie, Frank Hobbie’s stepmother.
She said her grandson, Ty, was the only one who survived. The infant suffered serious injuries and was airlifted to Texas.
“We’re all devastated,” Hobbie said.
One of the first to search the area was a man who found one of the girls under a destroyed trailer. "She was still holding her baby doll," Courtney Glitch told KFOR.
Some storm sirens in the town failed to sound after a tower used to activate the warning system was damaged by lightning. But others near the mobile home park said they had heard a siren.
However, residents and officials in at least one of the affected states credited days of urgent warnings from forecasters for saving lives.
Two other victims in the nearby town of Tangiers – a man named by the Oklahoma state medical examiner's office as Darren Juul, and an unidentified 10-year-old girl – were also killed in the storm.
And a man who had been hospitalized with critical injuries died early Monday.
Multiple injured residents were also transported to area hospitals.
The storms also left thousands without power in Kansas, hit an aircraft fuselage production facility, and damaged up to 90 percent of homes and buildings in a small Iowa town. The governors of Kansas and Oklahoma declared states of emergency.
The National Weather Service website listed only one tornado warning on Monday morning, for southeastern San Patricio county in south-central Texas, however there were high wind warnings in effect for parts of South Dakota, with gusts of up to 45 mph.
The weekend storms were part of an exceptionally strong system tracked by the National Weather Service's Storm Prediction Center in Norman, Okla., which specializes in tornado forecasting. Before the weekend, the center took the unusual step of warning people more than 24 hours in advance of a possible "high-end, life-threatening event."
"We can't do this with every event," said the center's Ken Miller, noting that many storm systems are not as easy to predict.
Miller said he was pleased the warnings were heeded.
"We measure our success by how the public reacts," he said. "Do they take precautions seriously and act on them?"
Dire language of warnings
In south-central Kansas, Sedgwick County Emergency Management Director Randy Duncan credited the dire language of the warnings with saving lives.
"People become used to those warnings. That is a dangerous complacency," Duncan said. "We need to break through the clutter of everyday noise to get people's attention."
Woodward city manager Alan Riffel told CNN that all the missing people had been accounted for, but 89 homes and 13 businesses had been destroyed.
"It's remarkable we didn't have more loss of life," Governor Mary Fallin told a news conference, saying many Woodward residents had either gone to sleep or dropped their guard after an earlier series of storms swept through the area.
She spoke to several whose homes were struck, including a man who said he was asleep on his sofa with his dog when the tornado hit, depositing them unhurt in the backyard.
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, some 75 to 90 percent of the town's buildings and homes were damaged or destroyed by the storm, Fremont County Emergency Management Coordinator Mike Crecelius said. Only minor injuries were reported.
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.
Reuters contributed to this report.
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