Back in June 2001, Tropical Storm Allison dropped immense amounts of rain across Texas before the remains of the storm moved slowly across the Southeast, causing flooding and damage from tornadoes across a wide swath of the eastern US.  As with many tropical storms, winds were not the main impact of the storm–instead the heavy rains from the slow-moving storm caused local flooding in many locations, washing out bridges and roadways and damaging or destroying many houses.  A number of locations in the Southeast reported more than 10 inches of rain in 24 hours.

You can read a complete description of the June 4-17 storm at Wikipedia at https://en.wikipedia.org/wiki/Tropical_Storm_Allison.  This summary from the Weather Prediction Center also gives a good look at the overall storm (link).  And Weather Underground provides some additional insight into the power of tropical systems here.

Allison_2001_rainfall