As The Scientific American noted a couple of years ago:
In a 2011 study published in Nature,
“. . . researchers examined daily records of rainfall, snowfall and sleet from more than 6,000 weather stations between 1951 and 1999. They found a rise in cases of extreme precipitation, such as rainstorms that deliver 100 millimeters of rainfall or more in 24 hours. The uptick could not be explained by natural climate fluctuations; instead it more closely matched what the patterns that computer models of climate predict for increasing concentrations of greenhouse gases. Humanity, in other words, has likely loaded the weather dice in favor of severe storms.”
Media Matters points out that this finding is cited by about 3% of newscasts on flooding in the US.