"We're going to have a pretty significant event starting probably late today over the Southern Plains," said Ken Cook, a meteorologist in the Wichita, Kansas, office of the National Weather Service.
Nick Wiltgen, a senior meteorologist for The Weather Channel, told NBC News that "the bullseye" for the weekend outbreak could be over the same areas damaged on Wednesday night, when dozens of twisters wrecked homes and took out power lines.
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On Friday, the greatest tornado danger was for a zone roughly bounded by the Texas cities of Lubbock, Abilene and Wichita Falls, forecasters said. Oklahoma City was also expected to be pounded by strong thunderstorms Friday evening.
Saturday was expected to be the main event, but the greatest threat shifted to the west of what forecasters first feared—meaning a lower risk for the major cities of Dallas, Oklahoma City and Wichita, Kansas.
An estimated 22 million people still face at least a slight risk of severe weather in the middle of the country on Saturday, including flash floods, baseball-sized hail and long-track tornadoes, which stay on the ground longer than other twisters.
In cities and towns from Nebraska to Texas, and especially in Oklahoma and Kansas, people are still picking up after the tornado outbreak on Wednesday night. More than four dozen twisters that killed at least one person and injured at least 13.