The International Fujita scale (abbreviated as IF-Scale) rates the intensity of tornadoes and other wind events based on the severity of the damage they cause.[1] It is used by the European Severe Storms Laboratory (ESSL) and various other organizations including Deutscher Wetterdienst (DWD) and State Meteorological Agency (AEMET). The scale is intended to be analogous to the Fujita and Enhanced Fujita scales, while being more applicable internationally by accounting for factors such as differences in building codes.
In 2018, the first draft version of the IF-scale, version 0.10 was published. This version was based on a 12-step rating scale. Over the next few years, dozens of tornadoes would be rated on this version of the scale. Most notably, the 2021 South Moravia tornado received a rating (IF4) and full damage survey on the IF-scale conducted by ESSL, the Czech Hydrometeorological Institute and four other organizations.[2] On May 6, 2023, version 0.99.9d was published, which changed it to a 9-step rating scale.[3] In late July 2023, the first official version of the IF scale was published.[4]