Just one twister can cause devastation. But when outbreaks bring dozens of tornadoes over days, they can leave a path of death and destruction across vast regions. And new research shows tornado outbreaks are getting more dangerous: More tornadoes are hitting during each round, even though the overall annual number of American twisters hasn’t changed. Scientists aren’t sure yet if there’s a climate change connection, or whether things will continue to get worse.
(Credit: Dan Bishop/Discover after Tippett et al. 2016 Science)