Shut circulation. People with optimum sustained winds of 39 mph or better are known as tropical storms. Each time a storm's utmost sustained winds access 74 mph, it is referred to as a hurricane. The Saffir-Simpson Hurricane Wind Scale is often a 1 to 5 rating, or classification, according to https://messiahlicum.dbblog.net/4122686/the-greatest-guide-to-hurricane