Derechos are a widespread and damaging group of severe thunderstorms. They often have rapid forward speeds. They have a distinct appearance on radars, known as bow echos. They have very strong winds. Unlike other thunderstorms, derecho storms usually hit suddenly, with strong hurricane force winds, spraying rain, and frequent lightning from all directions. A derecho can create heavy damage in only a short time. These storms usually happen in North America, although they can occur elsewhere around the world. Winds with these storms can exceed 100 mph in certain cases.