Severe storms and tornadoes have been unusually active so far this year. This could be why

Back-to-back-to-back deadly and destructive tornado outbreaks in recent weeks have put a punctuation mark on what’s been an unusually active start to the year for thunderstorms in the United States.

The typical peak of severe thunderstorm season is still a few weeks away, so why has it been so busy so early? The answer might be found in…