Six people were dead on Monday after more than 100 twisters tore through a wide swath of the central United States over the weekend, leaving a trail of devastation from Texas to Wisconsin.
All six fatalities occurred in the state of Oklahoma, according to US news reports which had reported five dead shortly after the tornadoes hit.
Reports said a sixth victim who succumbed early on Monday in the hard-hit town of Woodward, population about 12,000 which also reported 30 people injured after being hit by a ferocious tornado.
The National Weather Service said that the immediate threat of more tornadoes had diminishedon Monday but residents of so-called Tornado Alley -- the plains states of Texas, Oklahoma, Kansas, Nebraska and South Dakota where tornadoes are prone to strike -- were bracing for the possibility of an especially violent storm season, according to meteorological forecasts.
And a report last month found that the traditional boundaries of Tornado Alley are expanding deeper into the US South and Midwest, meaning that the devastation could affect an even larger section of the US population.
The report was released in late March by the CoreLogic private research group, found that Florida, Iowa, Louisiana and Mississippi have joined Kansas among the ranks of the most tornado-hit US states.
The report states that a tornado risk now extends across much of the eastern half of the nation, and at least 26 states face some danger of being hit.
By early Sunday, over 100 tornadoes had been reported in the region, and the National Weather Service warned that "severe storms" were possible in a huge swathe of the country, from Texas to Wisconsin.
"Severe thunderstorms, including tornadoes" were expected later over parts of the Upper Mississippi Valley.
"It's really a devastating thing to our city," Woodward Mayor Roscoe Hill told reporters. "I think the main thing is all you can do is pray for us."
Gale-force winds and hail the size of golf balls leveled buildings, blew roofs off homes, uprooted trees and toppled power lines, leaving mounds of debris. Woodward County Emergency Manager Matt Lehenbauer told local media that at least 89 homes and 13 businesses were destroyed in the area.
Classes were canceled for Monday due to the storm damage, but all schools were due to be reopened Tuesday.
"We still have so many families without electricity, and a lot of the roads aren't open for our routes," Woodward Public Schools Superintendent Tim Merchant told The Oklahoman daily newspaper.
A tornado leveled most of the tiny town of Thurman, Iowa, where authorities evacuated the town's population of about 300 people. Many Thurman residents took up temporary shelter at a high school in nearby Tabor, CNN reported.
The damage was estimated to be as much as $283 million in the Wichita, Kansas area, The Kansas City Star said, citing a preliminary assessment by city and county officials.
"Things were flying and everyone screamed," Kristin Dean told the newspaper after heavy damage at the Pinaire Mobile Home Park where she lives. "We all kind of huddled together."
But the storms caused few casualties thanks to early warnings from meteorological services that urged people to take precautions well in advance.
It was just the second time in US history that the National Weather Service's Storm Prediction Center issued a high-risk warning more than 24 hours in advance.
The Federal Emergency Management Agency state and federal officials were evaluating the damage as the agency collaborated with state and local officials impacted by the deadly tornadoes and severe storms.
American Red Cross workers were operating shelters and providing meals, as well as relief and cleanup supplies such as comfort kits, tarps, coolers and rakes.
"Our thoughts are with everyone affected by these tornadoes," Red Cross Disaster Services senior vice president Charley Shimanski said in a statement. "Red Cross chapters are already offering folks food and a safe place to stay and more workers and equipment are being sent it to help people who were in the path of these storms."