The two pictures above is Tetsuya T. Fujita, the man who invented the Fujita "F" Scale.
The two pictures above is Tetsuya T. Fujita making an artificial tornado
This is a graph of the percent of tornadoes strength that occurred from 1950-1994
Tornadoes cause a lot of damage as well as devastation. There is no accurate way to measure the wind speeds near or even in a tornado. Because tornadoes are fairly small storms and it isn’t easy to predict their touchdowns, getting meteorological instruments into or near a tornado is neither practical nor safe. Although storm chasers hypothesize the intensity of most tornadoes based on the strength, the size of the tornado, and how fast debris appears to be traveling through the air, there is no exact way to prove that they are merely correct.
Although we can not be positively sure, there is one way that meteorologists can tell how much damage a coming tornado will cause. This is done by using the F-Scale, or the Fujita Scale. In the early 70’s, the F-Scale was introduced by a man named Tetsuya T. Fujita. The F-scale describes different levels of damage caused by a tornado by estimating the wind speeds of it. This scale goes from light damage (F-0) to incredible damage (F-5)
The first level of damage is F-0 or “light damage.” A tornado has the level of an F-0, if it has winds less than 73 miles per hour. If you were to observe the aftermath of an F-0 tornado, you would most likely see branches broken off trees, minor damage to chimneys, shallow rooted trees pushed over, and sign boards damaged.
The second level of damage is F-1 or “moderate damage.” The wind speeds of a moderate damage tornado are 73-112 miles per hour. This combination of wind and debris causes the surface of roofs to peel off, mobile homes to be pushed off foundations or overturned, and moving automobiles to be blown off the road.
The third level of damage is an F-2 or in other words “considerable damage.” The winds in this tornado can be up to 157 miles per hour! That’s faster than most cars. The things you would see after this tornado hits would probably be roofs torn off the frames of houses, mobile homes demolished, box cars overturned, large trees uprooted and snapped, and cars that were lifted off the ground smashed into pieces.
The fourth level of damage is an F-3 tornado or “severe damage.” This tornado’s can get up to 206 miles per hour! To give you a perspective of how fast that is, it would be like going on the fastest rollercoaster in the world (Top Thrill Dragster, 120 mph), but almost twice as fast and without any seatbelts or protection. The speed of this tornado leaves roofs and some walls torn off well constructed houses, trains overturned, most incredibly large trees uprooted and thrown miles away or snapped, and heavy cars that had been lifted and are left in pieces.
The fifth level of damage from a tornado is an F-4 or “devastating damage.” These type of tornado’s get up to 260 miles per hour! That’s 30 mph faster than a Japanese Bullet train! During this tornado, you are going to see well constructed houses leveled to the ground, structures with weak foundations blown away some distance, and cars thrown.
Although they are very rare, the sixth and final level of damage ever recorded is an F-5, otherwise known as “Incredible damage.” These tornadoes can get up to 320 miles per hour! Wow, that’s fast! Also in this type of tornado, incredible phenomena will occur. You would see strong frame houses leveled off foundations and be swept away, cars flung through the air in excess of 100 meters, and almost every tree debarked. Obviously most deaths occur during an F-5 tornado.