EF4

EF4 is a rating on the Enhanced Fujita scale used to classify the intensity of tornadoes. The Enhanced Fujita scale, introduced in 2007 in the United States, replaced the original Fujita scale to provide more consistent wind estimates by evaluating the damage caused by a tornado rather than relying solely on observed wind speeds. The scale ranges from EF0 to EF5 and is applied by comparing observed damage to a set of damage indicators and degrees of damage.

EF4 corresponds to devastating damage, with estimated wind speeds from 166 to 200 mph (267 to 322 km/h). Ratings are determined from the extent and type of damage to structures, vegetation, and debris, using 28 damage indicators that cover different building types and outdoor features. After a tornado, survey teams inspect the path and assign an EF rating based on the most significant damage observed along the damage path, though ratings can vary along the length of a tornado’s path.

In practice, EF4 damage typically includes the near-total destruction of well-constructed homes, heavy damage to large buildings, and the uprooting or snapping of many trees; cars and other heavy objects may be thrown significant distances. It is important to note that wind speed estimates are inferred from damage and can be influenced by construction quality, debris, and topography.

The EF scale is used by meteorological agencies in the United States and other countries to communicate tornado severity, support risk assessment, and inform public safety responses.