By NBC News, msnbc.com staff and news services
Updated at 12 p.m. ET
BRANSON, Mo. -- At least 13 people were killed overnight as a line of tornadoes marched across the Midwest, flattening parts of several towns, officials said Wednesday. Hardest hit was Harrisburg, Ill., where 10 deaths were reported, along with nearly 100 injuries and at least 200 homes destroyed or damaged.
Forecasters warned more twisters could strike the Tennessee Valley and southern Appalachians through Wednesday evening as the storm system moved east.
Ten of the deaths occurred in Harrisburg, the local coroner told state officials. What is thought to have been a tornado swept through the town around 5 a.m. local time, destroying 35-40 homes, according to local TV station KFVS12.
Three other deaths were reported in Missouri, where storms included a suspected tornado that hit a mobile home park outside the town of Buffalo. One person died in the mobile home park and around a dozen people were injured. Two others died in the Cassville and Puxico areas of Missouri.
On Tuesday night, at least 8 people were injured when a suspected tornado ripped through Harveyville, Kan. At least three of the injured are in critical condition, according to weather.com, and 40 percent of the town suffered damage.
NBC affiliate KSHB TV reported that an apartment complex and a church were among the damaged buildings in the town of about 250 people.
Kansas Gov. Sam Brownback issued a disaster declaration for the area, parts of which were without power.
Other hard-hit areas included Branson, the tourist hub, and Lebanon in Missouri.
In Branson, 32 people were treated at one hospital for injuries, mostly cuts and bruises. An apparent tornado moved through downtown Branson, heavily damaging the city's famous theaters and hopscotching up Highway 76, uprooting road signs and scattering debris.
The injuries could have been far worse had the storm hit next week, when the tourist season begins.
"If it was a week later, it'd be a different story," said Bill Tirone, assistant general manager for the 530-room Hilton and adjacent Branson Convention Center, where windows were shattered and some rooms had furniture sucked away by high winds. Hotel workers were able to get all guests to safety as the storm raged.
Mark Schiefelbein / AP
Storm debris is piled near the entrance to the Dick Clark's American Bandstand Theater in Branson, Mo., on Wednesday.
John Moore, owner of the damaged Cakes-n-Creams '50s Diner, said the apparent twister appeared to "jump side to side" as it moved down the entertainment district, right through the convention center, across a lake and into a housing division.
"The theater next to me kind of exploded. It went everywhere. The hotels on the two sides of me lost their roofs. Power lines are down. Windows are blown out," Moore said. "There's major, major destruction. There has to be millions dollars of damage all down the strip.
Paul Newton / The Southern via AP
This neighborhood was among the areas of Harrisburg, Ill., damaged overnight.
"Jennifer Verhaalen said she saw a white funnel cloud followed by a wall of rain as the storm closed in on the town around 1 a.m.
She said she retreated to a back bedroom with her husband as the storm slammed into two hotel buildings, tearing the roof off one.
PhotoBlog of the destruction
Across the road, a strip mall lay in tatters, its roof missing and several walls collapsed.
Branson has long been a touristy outdoor destination for visitors who came to see the beauty of the surrounding Ozarks. But the city rose to prominence in the 1990s largely due to the theater district, where venues featured the star power of country music and celebrities including the Osmonds and Andy Williams.
John Hanna / AP
Damage in Harveyville, Kan., includes this home.
In Lebanon, a tornado was reported at 12:25 a.m. and numerous reports came in of damage in the area. A tractor-trailer was reported to have been blown off Interstate 44 nearby.
Newburgh, Ind., also saw damage from severe storms. Several homes and a business were hit, though no injuries or deaths were reported.
Mathew Fowler / Harveyville Gazette via AP
Damage is seen Wednesday morning in Harveyville, Kan., after an apparent tornado passed through Tuesday night.
Weather.com earlier said that "scattered severe storms" had been expected to sweep from the Plains eastward into the mid-Mississippi Valley and portions of the Mid-South Tuesday night into early Wednesday.
The National Weather Service said it was forecasting more tornadoes on Wednesday, including "one or two possibly strong" ones as well as "damaging wind over parts of the Tennessee Valley to southern Appalachians" into the evening.
The system also skirted northern Arkansas, bringing gusts of up to 60 miles per hour in the northwest. A wall cloud was reported in Cherokee Village, where trees were scattered along roads, the weather service said. Residents of Clay County in northeastern Arkansas reported hail the size of golf balls, and similar-sized hail was reported in Mountain Home.
In northern Oklahoma, gusts of up to 80 mph flipped trailers and damaged homes near Cherokee.
Tornado season normally starts in March, but it isn't unusual to see severe storms earlier in the year. Forecasters have a particularly difficult time assessing how serious a season will be in part because tornadoes are so unpredictable. This year, two people were killed by separate tornadoes in Alabama in January, and preliminary reports show 95 tornadoes struck that month.
NBC News and The Associated Press contributed to this report.
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