(CNN) — On a day when millions of Americans were traveling to see their families and friends for Christmas, a line of fast-moving storms threatened residents from the Mississippi Valley to the Ohio Valley.
A large and extremely dangerous tornado is moving through northwest Mississippi, the National Weather Service said Wednesday evening. The tornado touched down near Clarksdale, the service said. There were reports of major damage to buildings in Sardis, about 45 miles east of Clarksdale.
The National Weather Service also issued a tornado emergency declaration for the small town of Holly Springs, which was next in its path. According to the National Weather Service, a tornado emergency means that significant widespread damage is expected with a high likelihood of fatalities.
At least four people were injured in the unincorporated area of Coahoma County known as Bellview, Board of Supervisors President Paul Pearson said. One person was in critical condition, he said.
Video from CNN affiliate WREG showed three houses in Como, just north of Sardis, that were badly damaged. Another looked to be a total loss.
Panola County Sheriff Dennis Darby told the Memphis, Tennessee-based station that no one was injured in that area.
There was one minor injury, he said, to the driver of a tractor-trailer that was blown over not far away on Interstate 55.
Daniel Cole, the county’s director of emergency management told CNN that in a separate wreck another motorist was injured when the tornado barreled through.
“It was on the ground all the way through the county,” said Cole. He added that in the county, which is 800 square miles, two homes had been destroyed and five damaged.
The storms have already killed one person.
An 18-year-old woman in Arkansas died Wednesday morning when a tree fell through her roof. Four other people in the house, including an 18-month-old, survived. The baby was hospitalized.
About 45 million people could be affected by the storms, which prompted a string of tornado warnings and watches in nine states. There also were watches and warnings for severe thunderstorms and flash floods.
The Storm Prediction Center in Norman, Oklahoma, issued a Particularly Dangerous Situation tornado watch for the following areas: southeast Arkansas, far northeastern Louisiana, northern and western Mississippi, and western Tennessee. The watch area includes all the Memphis metropolitan area. The watch is in effect until 9 p.m. ET.
The Particularly Dangerous Situation wording is used in tornado watches for rare situations when long-lived, intense tornadoes are likely. PDS watches are issued when in the opinion of the forecaster, the likelihood of significant events is boosted by very volatile atmospheric conditions.
The primary threats include several tornadoes with a few intense tornadoes likely, scattered damaging wind gusts to 75 mph, and isolated large hail, the Storm Prediction Center said.
Some storms were moving at 55 to 60 mph. One tornado had been spotted in Mississippi.
CNN’s Dave Alsup contributed to this report.
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