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Winter Weather: 'Siberian Express' Coming to Iced-Over South

A deep freeze will take hold Wednesday night and Thursday, pushing low temperatures below zero in parts of Tennessee, Kentucky and North Carolina.

Potentially record-setting cold is about to cause more misery for more than 250,000 people still struggling without power across the Southeast.

Blackouts were reported from Arkansas to the Carolinas after a winter storm brought snow and ice to the region earlier this week. More than a quarter-million homes and businesses, mostly in Georgia, were still in the dark early Wednesday when a blanket of cold air began to descend from the Upper Plains.

The worst of the cold is expected Thursday morning as an air mass that some meteorologists call the Siberian Express dives south. Parts of Tennessee and Kentucky could set records for the coldest Feb. 19 on record. Some areas in those states could drop below zero on Thursday, with double digits below zero possible in isolated patches.

“The cold outbreak of 1899 is kind of the benchmark for cold outbreaks to beat, and this one looks like it’ll either compare or be even more impressive,” said Kevin Roth, lead meteorologist at The Weather Channel. “The cold records likely to fall have been standing since before the automobile was invented in the U.S.”

In Nashville, Tennessee, the forecast low for Thursday morning is 3 below. That would be the latest in the year that Nashville has been at zero or below in the 144 years that records have been kept there, and the frigid temperatures should stick around at least through Friday.

Almost 1,700 departures and arrivals were again canceled at U.S. airports on Tuesday, more than a third of them at the airports in Charlotte, North Carolina, and Nashville.

At least seven people were killed on icy roads in Indiana, Kansas, North Carolina, Tennessee and Virginia.

Two of them, Kristi Clark, 34, and her son Carter, 10, were killed on Interstate 65 in Franklin, Tennessee, after they stopped to help five people in an SUV that hit a patch of black ice and rolled over late Monday. Two of the five people in the SUV were critically injured, police said.

Franklin Police Chief Deborah Faulkner called Clark and her son “heroes” and “good Samaritans [who] put themselves in harm’s way to help a stranger.”

She added: “The goodness in their hearts that prompted them to do that will never be forgotten.”

At Arkansas Children’s Hospital in Little Rock, emergency room physicians treated at least a half-dozen children with significant injuries from in sledding accidents, said Dr. Mary Aitken, a pediatrician and director of injury prevention at the hospital.

While the ice looks like snow, it’s not, and “it definitely behaves much differently,” Aitken told NBC station KARK of Little Rock.

Jacob Sisterhen, 7, broke his leg and suffered a concussion when his sled slammed into a parked car, said his mother, Dr. Laura Sisterhen — who's also a pediatrician at Children's Hospital.

“It happened so fast I couldn't stop him,” Sisterhen told KARK. “I would have if I could have.”

Meanwhile, the relentless cycle of snow across the East was set to continue with a new system expected to bring up to 3 inches through the Ohio Valley and Appalachians on Wednesday.

This system was expected to move into Washington, D.C., New York City, and Philadelphia on Thursday morning, with a chance heavier snow could develop in Maine into the night.

This was set to be followed by a wintry mix of snow, sleet and freezing rain stretching from the Rockies to parts of the South and East from Friday through Sunday, according to The Weather Channel.