RUSK COUNTY, Texas — The original Fujita Scale was created in 1971 by Dr. Ted Fujita with the purpose of measuring tornado intensity based on the damage and an estimated range of wind speeds.
That scale was revised in 2007 to the version we use today, known as the Enhanced Fujita Scale (EF Scale).
As National Weather Service Shreveport Warning Coordinator, Charlie Woodrum, explains, the enhanced version shows a smaller range of wind speeds and a larger focus on the destruction left behind.
"Several wind studies that have been completed by wind engineers and wind scientists found that much less wind is needed to do catastrophic damage," Woodrum said.
The original Fujita scale had an F5 tornado associated with winds around 300 mph. The Enhanced Fujita Scale dropped that wind range to 200 mph for an EF-5 rating, and it also considers what type of structure was destroyed.
"In order to determine the damage wind speed, we have to look at different damage indicators along the tornado's path to determine what the strength of the wind was and what the EF scale rating was," Woodrum said.
Once a tornado has touched down in a known area, survey teams will arrive at that area once the weather has cleared to look at the degree of damage left behind. The objects often observed such as houses, buildings, trees, or other objects are known as damage indicators. Each damage indicator can have a different degree of damage based on the strength to which it was built to withstand prior to the storms. This evaluation is known as the degree of damage and it helps determine the wind speeds inside the storm.
Areas like Mt. Enterprise had a degree of damage linked to an EF-2 tornado with winds peaking at an estimated 115 mph over a length of more than 21 miles and a width of 300 yards.
Trees were uprooted, homes were damaged and a church steeple was swept off of its foundation.
No matter the EF rating, it is important to remember that even the weakest tornadoes can cause injury or even death. The main cause of death related to tornadoes is from flying debris.