CNN CNN Newsroom July 22, 2013 17:43:00
The united states? in atlanta it was raining and raining all weekend. >> in arizona when a storm pops up they don't move very fast. they just sit there and it rains and rains and then it dies off. the video here is out of utah. there are flash flood chasers. this is what a flow debris. >> what's flowing there? >> that's trees and stuff on the ground. at the beginning of this flow it's almost like a little beaver dam. that water gets very quick and very high. you don't see the water rising slowly. it comes down like a wall of this muck. those are sticks and twigs.
Source: archive.org