The Oklahoma City metropolitan area (of which Moore oklahoma is a part) is located in Tornado Alley and is subject to frequent and severe tornadoes and hailstorms, making it one of the most tornado-prone major metropolitan areas in the world.
Moore Oklahoma itself has seen nine tornadoes between 1998 and 2015, three of them big enough to claim lives and cause catastrophic damage.[19] The city of Moore was damaged by significant tornadoes on October 4, 1998; May 3, 1999; May 8, 2003; May 10, 2010; and May 20, 2013, with weaker tornadoes striking at other times, notably May 31, 2013 and March 25, 2015. Moore is located in Tornado Alley, a colloquial term for the area of the United States where tornadoes are most frequent. About 20 tornadoes occurred in the immediate vicinity of Moore from 1890 to 2013.[20] The most significant tornadoes to hit Moore occurred in 1893, 1999, and 2013.
During the tornado outbreak on May 3, 1999, a tornado hit Moore and nearby areas. The tornado, which was rated an F5 on the Fujita scale, was the most costly tornado in history at the time (not adjusted for changes in inflation and population). The tornado had an approximate recorded wind speed of 301 mph (484 km/h) as sampled by mobile Doppler radar, the highest wind speed ever recorded on Earth. It left a swath of destruction over 1 mile (1.6 km) wide at times, and 38 miles (60 km) long. It killed a total of 36 people in the Oklahoma City metropolitan area. This was the deadliest F5 tornado recorded since the Delhi, Louisiana tornado in 1971 until this mark was eclipsed by several tornadoes in 2011.
On May 20, 2013, parts of Moore and neighboring Newcastle and southern Oklahoma City, were affected by a violent tornado. Classified as EF5 on the Enhanced Fujita scale, it had estimated wind speeds of 200–210 mph (320–340 km/h), a maximum width of 1.3 miles (2 km), and a path length of 17 miles (30 km). Entire subdivisions were destroyed; the tornado struck Briarwood and Plaza Towers elementary schools in Moore while school was in session. The Oklahoma Medical Examiner’s office reported that 24 people were killed, including 10 children. Over 140 patients, including at least 70 children, were treated at hospitals following the tornado. It was the deadliest U.S. tornado since the Joplin, Missouri tornado that killed 158 people in 2011.