3 storm chasers die pursuing Texas tornadoes; 200,000 residents without power

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Powerful thunderstorms and tornadoes and golf ball-size hail moved through parts of Texas and Oklahoma overnight, causing nearly 200,000 people to lose power in the Dallas area. Three storm chasers were killed. NBC’s Tammy Leitner reports for TODAY, and Al Roker delivers his forecast from the University of Tennessee.