NOVA

Deadliest Tornadoes

Passport Season 39 Episode 10 | 52m 52s

In 2011, the worst tornado season in decades left a trail of destruction across the U.S., killing more than 550 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 bad will it get?

Aired: 04/10/12

Rating: TV-PG

Video has closed captioning.

Problems Playing Video?

National corporate funding for NOVA is provided by Draper. Major funding for NOVA is provided by the David H. Koch Fund for Science, the Corporation for Public Broadcasting and PBS viewers.