The strength of tornadoes is rated on the Enhanced Fujita, or EF, Scale.
The scale runs from 0 to 5 and rates tornadoes after they’ve hit by assessing damage to determine wind speed. Estimates are based on damage to trees, institutional buildings and homes, making it harder to gauge tornadoes that leave little damage or happen in open space.
The scale is named after Tetsuya “Ted” Fujita, an engineer and meteorologist who developed the original version of it in 1971.
Here are the Enhanced Fujita Scale ratings used today by the National Weather Service and the kind of damage associated with each:
EF0: 65- to 85-mph wind gusts
These tornadoes are the least destructive and typically break tree branches, damage road signs and push over small, shallow-rooted trees.
EF1: 86- to 110-mph wind gusts
With similar wind speeds to weak hurricanes, these tornadoes can push moving cars off course, shift mobile homes from their foundations and remove roof surfaces.
EF2: 111- to 135-mph wind gusts
Significant damage starts to emerge from these tornadoes, which can snap or uproot trees, destroy mobile homes and tear roofs completely off homes.
They also can pick up small objects and turn them into dangerous projectiles.
EF3: 136- to 165-mph wind gusts
These tornadoes produce severe damage, uprooting nearly all trees in their path, blowing over large vehicles like trains and buses and significantly damaging buildings.
Less than 5% of all tornadoes are rated EF3 or higher.
One such tornado in March 2022 struck near New Orleans, hitting Arabi, Louisiana, with 160-mph winds. At least one person was killed and eight hospitalized after the storm ripped through homes and businesses, leaving a trail of destruction.
EF4: 166- to 200-mph wind gusts
Easily destroying homes, tossing cars and downing large trees, these tornadoes can be devastating.
One ripped through eastern Alabama in 2019 with top winds estimated at 170 mph. Blazing a track a mile wide, it killed at least 23 people, including three children.
Another EF4 tornado was part of an outbreak that tore through eight states just two weeks before Christmas 2021. It destroyed part of Mayfield, Kentucky, and left at least 74 people dead in that state alone.
EF5: 200+-mph wind gusts
These monsters cause complete devastation, flattening nearly everything in their path.
They are rare, with only 59 have been recorded in the United States since 1950, according to the Storm Prediction Center.
The most recent struck in 2013 in Moore, Oklahoma, killing 24 people, including several students at an elementary school where only a few walls were left standing.