May was the wettest month in the recorded history of US
May was the wettest month in the contiguous United State since precipitation started being recorded 121 years ago. Not only did the nation receive more rainfall last month than any other month of May, it received more rainfall than any other month period.
From the National Centers for Environmental Information report:
"The heavy rains in the central U.S. were accompanied by severe weather with over 400 preliminary tornado reports, the most since April 2011. The flooding rains and severe weather resulted in dozens of fatalities and widespread property damage."