Text Size: Small Medium Large

Nova - Deadliest Tornadoes

In April 2011, the worst tornado outbreak in decades left a trail of destruction across the U.S., killing more than 340 people. Why was there such an extreme outbreak? How do such outbreaks form? With modern warning systems why did so many die? Is our weather getting more extreme -- and if so how...
Tuesday May 19th8:00pmWGBY 57/HD
Wednesday May 20th1:00amWGBY 57/HD
Saturday May 23rd4:00amWGBY 57/HD