Maybe not:

It’s tempting to assume that climate change is responsible for an increase in the number devastating tornadoes, like those that ravaged Joplin, Missouri, in 2011, and Hattiesburg, Mississippi, in February. But if these tragedies are indeed becoming more common, it’s mainly because of population growth. Sixty years ago, yesterday’s tornado might not have killed anyone at all: Moore had a population of 942 in 1950, but today has more than 56,000 residents.

There has been an increase in the number of reported tornadoes: Since 1950 (or even over just the last two decades), the U.S. has added Doppler radars capable of detecting tornadoes, and population growth has increased the number of on-the-ground observations. But it’s unclear whether tornadoes have become more frequent, let alone because of climate change.

Enten has more on the subject.