Meteorologists use damage to estimate the maximum winds of a tornado at any given point. Engineers and meteorologists worked together to figure out how strong winds have to be to cause certain levels of damage.

Dr. Theodore Fujita pioneered the study of tornado damage in the mid-20th century. He developed the Fujita (F) Scale to rate damage to buildings, vehicles, and vegetation on a scale ranging from F0 (weak) to F5 (extreme).

Scientists began using a revamped version of the scale in 2007. This Enhanced Fujita (EF) Scale reflects the fact that objects like homes and trees require much lower wind speeds to incur damage.

The Fujita/Enhanced Fujita scales are damage rating scales. Some ratings are controversial as a result. There are several cases where meteorologists have gotten accurate measurements of a tornado's winds, but couldn't find damage to warrant a higher F/EF-Scale rating.

Scale-topping EF-5 tornadoes probably aren't as rare as they seem. These high-end tornadoes produce maximum winds stronger than 200 mph.

Since the EF-Scale is based on damage, meteorologists have to look for certain levels of destruction amid the rubble in order to assign a tornado its ultimate rating. Very few structures can withstand the 201+ mph winds needed to achieve EF-5 level damage.

Homes are usually uninhabitable and need extensive repairs after an EF-2 tornado. Many homes that suffer EF-3 damage are total losses, and EF-4 damage often causes complete failure of the structure with only the occasional interior room left standing.

An EF-5 tornado scrubs a home clean off its foundation, leaving behind a bare slab in its wake. Given this extreme level of destruction, surveyors have to look for context clues to find EF-5 level damage. This includes things like catastrophic damage to reinforced school buildings and less conventional damage like exceptionally heavy objects lifted and tossed a long distance.

I wrote more about this topic for The Weather Network in April 2024.