May 21–26, 2011 tornado outbreak sequence

Tornado outbreak sequence of May 21–26, 2011

High-end EF4 tornado that struck Chickasha, Oklahoma on May 24th.
Type	Tornado outbreak
Duration	May 21 – May 26, 2011
Tornadoes confirmed	241 confirmed
Max rating1	EF5 tornado
Duration of tornado outbreak2	Six days
Damage	~$7 billion (2011 USD)
Casualties	181 fatalities (+ 3 non-tornadic), 1,589 injuries
Areas affected	Midwestern United States, Southern United States
1Most severe tornado damage; see Enhanced Fujita scale 2Time from first tornado to last tornado

¹Most severe tornado damage; see Enhanced Fujita scale

The tornado outbreak sequence of May 21–26, 2011 was a deadly series of tornado activity across the Midwestern and Southern regions of the United States. It was one of the largest tornado outbreaks on record. Most of the tornadoes developed in a corridor from Lake Superior southwest to central Texas; isolated tornadoes occurred in other areas. An especially destructive tornado destroyed one-third of Joplin, Missouri, resulting in 162 deaths and 1000 injuries. The Joplin tornado is the deadliest in the US since April 9, 1947, when an intense tornado killed 181 in the Woodward, Oklahoma area. Tornado-related deaths also occurred in Arkansas, Kansas, Minnesota, and Oklahoma. Overall, the tornado outbreak resulted in 184 deaths, 6 of those non-tornadic, making it second only to the 2011 Super Outbreak as the deadliest since 1974, and the second costliest tornado outbreak in US history behind that same April 2011 outbreak, with insured damage estimated at $4–7 billion.

April 2011 was the most active month for tornadoes on record, capped by a very large tornado outbreak (the largest on record) that killed 324 people in the final week. In contrast, the first three weeks of May were remarkably quiet; only a few isolated tornadoes were confirmed. However, that pattern changed abruptly as a strong low pressure area and associated dry line and cold front tracked eastward.