(CNN) -- After a day of recovery for battered regions of the Midwest and South, a line of storms stretching from Illinois to Louisiana will bring the threat of tornadoes and severe weather Friday, forecasters said.
Areas most at risk for twisters are southern Indiana, southern Ohio, most of Kentucky, central Tennessee, northeastern Mississippi and northwestern Alabama.
The storms are forecast to rapidly develop around noon ET Friday. The most likely window for tornadoes will be between 4 p.m. and 8 pm. ET Friday, according to CNN meteorologist Sean Morris.
There is the potential for widespread damaging wind gusts, large hail and violent tornadoes in some areas.
Storms will begin to weaken during the late evening as they move eastward toward the Appalachians. The severe weather threat will diminish overnight Friday into Saturday morning, Morris said.
The tornado outbreak that began Tuesday night left 13 dead across Kansas, Missouri, Illinois and Tennessee and battered parts of Kentucky as well. The latest death was reported in Kansas, where authorities said 53-year-old Richard Slade died Thursday from injuries suffered when a tornado struck Harveyville on Tuesday night.
Slade had been airlifted to a nearby Topeka hospital after being pulled from the wreckage of his home. The decision was made to take him off life support, officials said.
National Guard troops helped police and sheriff's deputies direct traffic and patrol streets in stricken areas of Missouri and Kentucky, while those who survived began the task of cleaning up.
In Harrisburg, Illinois, where the highest death toll occurred, a tree smashed in the front window of Chris and Alice Retzloff's home before dawn Wednesday. But their neighbor's house was "pretty much gone," Chris Retzloff told CNN's "Starting Point."
"Our damage was minimal compared to this," his wife added.
"We have a basement, and we went in our basement and huddled together with our dogs and the sirens went off," she said. "The wind was just immense, the sound, and then the next siren went off, and there was just this incredible pressure that we all had on us."
Four women and two men died in Harrisburg, about 30 miles north of the Kentucky border. The tornado that struck it had a preliminary rating of EF4, the second most powerful on the rating scale, according to the National Weather Service.
The twister appeared to have been on the ground for several miles, said Harrisburg Mayor Eric Gregg, and the path of destruction was about three or four football fields wide. Sheriff's deputes said about 100 people were injured and between 250 and 300 houses were damaged or destroyed.
Darrell Osman lost his mother to the storm. After the twister struck, he ran to her house, only to find nothing left.
"Her house was literally gone," Osman said. He found his mother in an ambulance, but she passed away later at a hospital.
In Washington, the White House said President Barack Obama called the governors of six states affected by the storms -- Illinois, Missouri, Kansas, Tennessee, Kentucky and Indiana -- "to offer condolences and assistance as necessary."
One person died in each of three towns in southern Missouri where the twisters struck -- Buffalo, Puxico and Cassville -- while another three died in two east-central Tennessee counties, authorities in those states reported.
A smaller tornado caused significant damage in the music resort city of Branson, Missouri.
The city's entertainment district, which boasts 50 theaters, had five or six damaged; of the city's 200 hotels, 15 had significant damage, Branson Mayor Raeanne Presley said. But she told CNN, "We'll be open for business in short order, and we will be helping those who suffered damage to rebuild."
Presley took cover with her family in the basement before immediately going out to survey the damage.
An EF2 tornado smashed at least seven miles of the city's commercial strip, leaving 33 people hurt, most with minor to moderate injuries.
The city's convention center and an attached Hilton were damaged, as was a portion of Branson Landing, a large shopping and entertainment complex.
City Administrator Dean Kruithof said about five or six of the city's roughly 40 theaters were damaged.
Two tornadoes were confirmed in Tennessee's Cumberland and DeKalb counties, between Nashville and Knoxville. The one that struck Cumberland County, where two people died, was an EF2 with top winds of around 125 mph, the weather service reported Thursday evening. The remaining fatality was from an EF1 twister with top winds around 90 mph, according to forecasters.
CNN's Logan Burruss, Kara Devlin, Joe Sutton and Phil Gast contributed to this report.