Tornado Outbreaks Are More Common — But We Don't Know Why
You're more likely to see a string of tornadoes today than you were 50 years ago, but scientists aren't sure what the cause is.By Evan Thomas | December 1, 2016
The most dangerous tornadoes are the ones that touch down one after the other. Most tornado deaths in the U.S. happen when six or more tornadoes affect a relatively small area — and new research shows these outbreaks are getting more severe.
We've seen that the frequency of these outbreaks is rising faster than expected. The chances of seeing a string of tornadoes has more than doubled in the past 50 years.