An EF5 tornado strikes the Oklahoma City suburb of Moore, killing 24 people and injuring 377 others.

The Enhanced Fujita scale is a scale that rates tornado intensity based on the severity of the damage a tornado causes. It is used in the United States and France, among other countries. The EF scale is also unofficially used in other countries, including China and Brazil. The rating of a tornado is determined by conducting a tornado damage survey.

The 2013 Moore tornado was a large and extremely violent EF5 tornado that ravaged Moore, Oklahoma, and adjacent areas on the afternoon of May 20, 2013, with peak winds estimated at 200–210 miles per hour (320–340 km/h), killing 24 people and injuring 212 others. The tornado was part of a larger outbreak from a slow-moving weather system that had produced several other tornadoes across the Great Plains over the previous two days, including five that had struck portions of Central Oklahoma the day prior on May 19. The tornado, along with the 2011 Hackleburg–Phil Campbell and El Reno–Piedmont tornadoes, has the highest rated official windspeed on the Enhanced Fujita scale, if the upper range is considered.

Oklahoma City, often shortened to OKC, is the capital and most populous city of the U.S. state of Oklahoma. It is the 20th-most populous U.S. city and 8th largest in the Southern United States with a population of 681,054 at the 2020 census, while the Oklahoma City metropolitan area with an estimated 1.49 million residents is the largest metropolitan area in the state and 42nd-most populous in the nation. The county seat of Oklahoma County, the city limits extend into Canadian, Cleveland, and Pottawatomie counties; however, areas beyond Oklahoma County primarily consist of suburban developments or areas designated rural and watershed zones. Oklahoma City ranks as the tenth-largest city by area in the United States when including consolidated city-counties, and second-largest when such consolidations are excluded. It is also the second-largest state capital by area, following Juneau, Alaska.