Rain and Floods

How fast do raindrops fall? Raindrops fall between 7 and 18 miles per hour (3 and 8 meters per second) in still air. The range in speed depends on the size of the raindrop. Air friction breaks up raindrops when they exceed 18 miles per hour. What is a flood? A flood results from days of heavy rain and/or melting snows, when rivers rise and go over their banks. What is a flash flood? A flash flood is sudden flooding that occurs when floodwaters rise rapidly with no warning within several hours of an intense rain. They often occur after intense rainfall from slow moving thunderstorms. In narrow canyons and valleys, floodwaters flow faster than on flatter ground and can be quite destructive. Do flash floods hurt people? Flash floods are the number one killer in the world. In U.S. Nearly 80% of people die of flash flood. How much water is needed for car to float away? A mere 2 feet of water can float a large vehicle or even a bus. This is why driving through flooded roads is not encouraged. Just 6 inches of rapidly moving flood water can knock a person down. Ends